bluuebunny/crossref_metadata_2025 huggingface dataset:
Interaction of IGF-Binding Protein-Related Protein 1 with a Novel Protein, Neuroendocrine Differentiation Factor, Results in Neuroendocrine Differentiation of Prostate Cancer Cells
Authors: Wilson Elizabeth M. , Oh Youngman , Hwa Vivian , Rosenfeld Ron G.
Published: January 2014

Neuroendocrine cells have been implicated in many cancers, including small cell lung, cervical, breast, and prostate carcinomas. The increase in neuroendocrine cell number in prostate cancer has been reported to correlate with poor prognosis, progressive tumors, and androgen insensitivity. The mechanisms involved in this differentiation remain unknown. IGF-binding protein-related protein 1 is a member of the IGF-binding protein superfamily and has recently been shown to exhibit differentiation and tumor suppression activity in prostate cancer cell lines stably overexpressing IGF-binding protein-related protein 1. From a yeast two-hybrid screen, a novel IGF-binding protein-related protein 1-interacting protein was identified. Immunocytochemical techniques indicate that this protein, 25.1, and intracellular IGF-binding protein-related protein 1 colocalize in the nucleus. When 25.1 is transiently expressed in a stable prostate cancer cell line overexpressing IGF-binding protein-related protein 1, cells assume a neuritic-like morphology with long dendritic-like processes and express the neuroendocrine markers chromogranin A and neuron-specific enolase. We propose that 25.1 (neuroendocrine differentiation factor) together with IGF-binding protein-related protein 1 can induce neuroendocrine cell differentiation in prostate cancer cells.
Allelotyping of Follicular Thyroid Carcinoma: Frequent Allelic Losses in Chromosome Arms 7q, 11p, and 22q
Authors: Kitamura Yutaka , Shimizu Kazuo , Ito Koichi , Tanaka Shigeo , Emi Mitsuru
Published: January 2014

The genetic mechanisms involved in development of follicular thyroid carcinoma are poorly understood, although allelic losses (LOH) in this type of tumor have been reported in small panels of follicular thyroid carcinomas examined in earlier studies. To clarify the real frequency of allelic loss we carried out a genome-wide allelotyping study of 66 follicular thyroid carcinomas using 39 microsatellite markers representing all nonacrocentric autosomal arms. The mean frequency of LOH was 9.2%, and the mean fractional allelic loss was 0.09. The most frequent allelic losses were detected in 7q (28%), 11p (28%), and 22q (41%). When we compared these results with our previous allelotyping studies using identical markers in other types of thyroid cancers, the 9.2% mean frequency of allelic loss detected in follicular thyroid carcinomas was higher than that in papillary thyroid carcinomas (3%), but not as high as that detected in anaplastic thyroid carcinomas (20%). Frequent allelic losses of markers on chromosomes 7q, 11p, and 22q suggest locations to examine for the presence of suppressor genes associated with the development of follicular thyroid carcinoma.
The −597 G→A and −174 G→C Polymorphisms in the Promoter of the IL-6 Gene Are Associated with Hyperandrogenism
Authors: Villuendas Gemma , San Millán José L. , Sancho José , Escobar-Morreale Héctor F.
Published: January 2014

To evaluate whether genetic variability at the IL-6 gene (IL-6) is associated with hyperandrogenism, we studied four common polymorphisms in the IL-6 promoter (−597G→A, −572G→C, −373AnTn, −174G→C) in 85 hyperandrogenic patients and 25 healthy women. We found 5 different haplotypes when considering the 3 biallelic polymorphisms at positions −597, −572, and −174 of IL-6 (relative frequencies in parentheses): GGG (0.505), AGC (0.377), GGC (0.059), GCG (0.055), and GCC (0.005). The frequencies of the GGG haplotype were 0.559 in patients and 0.320 in controls, whereas those of the AGC haplotype were 0.318 in patients and 0.580 in controls (χ2 = 12.145; P < 0.02). The −597G→A and −174G→C polymorphisms were in linkage disequilibrium (χ2 = 152.220; P < 0.00001), and were associated with patient or control status. −597G and −174G alleles were more frequent in patients in homozygosity or considering subjects homozygous and heterozygous for G alleles as a whole (P < 0.05 for all analyses).

In healthy women G alleles at −597 and −174 were associated with statistically significant higher circulating levels of IL-6 and basal cortisol, 11-deoxycortisol, and 17-hydroxyprogesterone and a tendency (P < 0.10) for higher total T concentrations compared with −597A and −174C alleles. On the contrary, neither the −572G→C nor the −373AnTn polymorphism was related to hyperandrogenism or influenced any clinical or biochemical variable.

In conclusion, our present results suggest that the −597G→A and −174G→C polymorphisms in IL-6 are involved in the pathogenesis of hyperandrogenic disorders.
Activation of the Bone Morphogenetic Protein Signaling Pathway Induces Inhibin βB-Subunit mRNA and Secreted Inhibin B Levels in Cultured Human Granulosa-Luteal Cells
Authors: Jaatinen Risto , Bondestam Jonas , Raivio Taneli , Hildén Kristiina , Dunkel Leo , Groome Nigel , Ritvos Olli
Published: January 2014

During the human menstrual cycle the circulating levels of inhibin B, a dimer of inhibin α- and βB-subunits, fluctuate in a fashion distinct from that of inhibin A, the α-βA-subunit dimer. This suggests that human inhibin subunits are each regulated in a distinct manner in human ovarian granulosa cells by endocrine and local factors. We have previously shown using cultures of human granulosa-luteal (hGL) cells that gonadotropins stimulate the steady state mRNA levels of inhibin α- and βA-subunits, but not those of the βB-subunit, which, on the other hand, are up-regulated by, for instance, activin and TGFβ. We recently identified the TGFβ gene family member bone morphogenetic protein-3 (BMP-3) as a granulosa cell-derived growth factor, but whether BMP-3 or other structurally related BMPs regulate human granulosa cell inhibin production is not known. We show here that hGL cells express mRNAs for distinct serine/threonine kinase receptors (BMP-RIA and BMP-RII) and Smad signaling proteins (Smad1, Smad4, and Smad5) involved in the mediation of cellular effects of BMPs. Subsequently, we determined in hGL cell cultures the effects of distinct members of the BMP family previously found to be expressed in mammalian ovaries. Recombinant BMP-2 induces potently in a time- and concentration-dependent manner the expression of the inhibin βB-subunit mRNAs in hGL cells without affecting the levels of α- or βA-subunit mRNAs. BMP-6 has a similar, but weaker, effect than BMP-2, whereas BMP-3 and its close homolog, BMP-3b (also known as growth differentiation factor-10) had no effect on inhibin subunit mRNA expression. hCG treatment of hGL cells was previously shown to abolish the stimulatory effect of activin on βB-subunit mRNA levels, and here hCG is also shown to suppress the effect of BMP-2. Furthermore, BMP-2 stimulates hGL cell secreted dimeric inhibin B levels in a concentration-dependent manner. Depending on the experiment, maximal increases in inhibin B levels of 6- to 28-fold above basal levels were detected during a 72-h culture period. We conclude that activation of the BMP-signaling pathway in hGL cells stimulates inhibin βB-subunit mRNA levels and leads at the protein level to a dramatic stimulation of secreted inhibin B dimers. Our results are consistent with the suggestion that in addition to the distinct activin- and TGFβ-activated signaling pathways, the BMP-activated pathway is likely to be implicated in the complex regulation of inhibins in the human ovary.
Insulin Inhibits the Pro-Inflammatory Transcription Factor Early Growth Response Gene-1 (Egr)-1 Expression in Mononuclear Cells (MNC) and Reduces Plasma Tissue Factor (TF) and Plasminogen Activator Inhibitor-1 (PAI-1) Concentrations
Authors: Aljada Ahmad , Ghanim Husam , Mohanty Priya , Kapur Neeti , Dandona Paresh
Published: January 2014

We have recently demonstrated that an infusion of a low dose of insulin reduces the intranuclear NF-κB (a pro-inflammatory transcription factor) content in MNC while also reducing the p;asma concentration of NF-κB dependent pro-inflammatory cytokines and adhesion molecules. We have now tested the effect of insulin on the pro-inflammatory transcription factor, early growth response-1 (Egr-1) and plasma concentration of tissue factor (TF) and plasminogen activator inhibitor-1 (PAI-1), two major proteins whose expression is modulated by Egr-1. Insulin was infused at the rate of 2 IU/h in 5% dextrose (100 mL/h) and KCI (8 mmol/h) for 4 h in the fasting state in ten obese subjects. Blood samples were obtained at 0, 2, 4 and 6 h. MNC were isolated and their total homogenates and nuclear fractions were prepared and Egr-1 was measured by electrophoretic mobility shift assay (EMSA). Plasma TF and PAI-1 were assayed by ELISA. There was a significant fall in Egr-1 at 2 (66 ± 14% of basal level) and 4 h (47± 17% of the basal level; P<0.01). PAI-1 levels (basal = 100%) decreased significantly after insulin infusion at 2 h (57 ± 6.7% of the basal level) and at 4 h (58 ± 8.3% of the basal level; P<0.001). Plasma TF levels (basal = 100%) decreased to 76 ± 7.7% of the basal level at 2 h and to 85 ± 10.4% of the basal level at 4 h (P<0.05). Thus, insulin reduces intranuclear Egr-1 and the expression of TF and PAI-1. These data provide further evidence that insulin has an anti-inflammatory effect including the inhibition of TF and PAI-1 expression. These effects suggest a potential beneficial effect of insulin in thrombin formation and fibrinolysis in atherothrombosis.
Steroid Receptor Coactivator Expression throughout the Menstrual Cycle in Normal and Abnormal Endometrium
Authors: Gregory Christopher W. , Wilson Elizabeth M. , Apparao K. B. C. , Lininger Ruth A. , Meyer William R. , Kowalik Ania , Fritz Marc A. , Lessey Bruce A.
Published: January 2014

The endometrium of reproductive aged women undergoes cyclic developmental changes in preparation for implantation in response to estrogen and progesterone. These steroids and their receptors are tightly regulated throughout the menstrual cycle, and their actions are facilitated by the presence of steroid receptor coactivators of the p160 family. In this study using immunohistochemistry and Western blot analysis, we characterize the expression patterns of three coactivators, steroid receptor coactivator-1, amplified in breast cancer-1 (AIB1), and transcriptional intermediary factor-2 in human endometrium obtained prospectively from normal fertile women throughout the menstrual cycle. With the exception of glandular AIB1, which increased in the late secretory phase, none of the coactivators changed significantly during the menstrual cycle. We compared coactivator expression patterns in fertile endometrium to the endometrium of anovulatory (proliferative; n = 3) and clomiphene-induced ovulatory (secretory; n = 13) women with polycystic ovarian syndrome (PCOS), a group that have a higher likelihood of developing estrogen-induced endometrial hyperplasia and cancer. To control for the effect of clomiphene citrate, an additional group was included consisting of ovulatory women treated with clomiphene citrate for “male factor” infertility. Compared with both fertile and infertile controls, PCOS women exhibited elevated levels of AIB1 and transcriptional intermediary factor-2 expression in both epithelial and stromal cells. We postulate that increased coactivator expression may render the endometrium more sensitive to estrogen. In support of this, we describe an increased expression of ERα (an estrogen-induced gene product) during the menstrual cycle in PCOS endometrium compared with fertile controls. In summary, we demonstrate that the expression of p160 coactivators are regulated in endometrium during the menstrual cycle in normal fertile women but are overexpressed in the endometrium of women with PCOS. Based on these findings, we suggest a possible mechanism to explain the poor reproductive performance observed in PCOS and the increased incidence of endometrial hyperplasia and cancer noted in this group of women.
Analysis of the Role of E2A-Encoded Proteins in Insulin Gene Transcription
Authors: Sharma Arun , Henderson Eva , Gamer Laura , Zhuang Yuan , Stein Roland
Published: January 2014

Pancreatic β-cell type-specific transcription of the insulin gene is mediated, in part, by factors in the basic helix-loop-helix (bHLH) family that act on a site within the insulin enhancer, termed the E1-box. Expression from this element is regulated by a heteromeric protein complex containing ubiquitous (i.e. the E2A- and HEB-encoded proteins) and islet-enriched members of the bHLH family. Recent studies indicate that the E2A- and HEB-encoded proteins contain a transactivation domain, termed AD2, that functions more efficiently in transfected β-cell lines. In the present report, we extend this observation by demonstrating that expression of full-length E2A proteins (E47, E12, and E2/5) activates insulin E element-directed transcription in a β-cell line-selective manner. Stimulation required functional interactions with other key insulin gene transcription factors, including its islet bHLH partner as well as those that act on the RIPE3b1 and RIPE3a2 elements of the insulin gene enhancer. The conserved AD2 domain in the E2A proteins was essential in this process. The effect of the E2A- and HEB-encoded proteins on insulin gene expression was also analyzed in mice lacking a functional E2A or HEB gene. There was no apparent difference in insulin production between wild type, heterozygote, and homozygous mutant E2A or HEB mice. These results suggest that neither the E2A- or HEB-encoded proteins are essential for insulin transcription and that one factor can substitute for the other to impart normal insulin E1 activator function in mutant animals.
Agonist and Antagonists Induce Homodimerization and Mixed Ligand Heterodimerization of Human Progesterone Receptors in Vivo by a Mammalian Two-Hybrid Assay
Authors: Leonhardt Susan A. , Altmann Magda , Edwards Dean P.
Published: January 2014

This study utilizes the mammalian two-hybrid system to examine the role of ligand in the dimerization of human progesterone receptor (hPR). The GAL4 DNA-binding domain and the herpes simplex virus VP16 transactivation domain were fused to the amino terminus of full-length hPR (both the A and B isoforms) to produce chimeric proteins. PR dimerization was detected by the ability of cotransfected GAL4/PR and VP16/PR chimeras in COS cells to induce expression of a reporter gene under the control of GAL4-binding sites (pG5CAT). Hormone agonist-dependent interactions were observed between the two like isoforms of PR (A-A and B-B) and between PR-A and PR-B (A-B), indicating that hormone can stimulate the formation of the three possible dimeric forms of PR within cells. In contrast, neither type I (ZK98299) nor type II (RU486, ZK112993) progestin antagonists stimulated interaction between these same hybrid PR proteins. However, activation of the VP16/PR chimera by antagonists on a progesterone response element-controlled reporter gene (DHRE-E1b-CAT) was only a fraction (4–13%) of that stimulated by agonist R5020. One possibility for the failure to detect an induction in the two-hybrid assay is antagonist-induced repression of the activity of the VP16/PR fusion protein rather than a failure of antagonists to stimulate interaction between the hybrid proteins. To test this idea, an UP-1 carboxyl-terminal truncation mutant of PR was used to construct the two-hybrid proteins. PR-UP-1 selectively binds antagonists, but not agonists, and is fully activated in response to antagonists. Both types of progestin antagonists stimulated interactions between GAL4/PR(UP-1) and VP16/PR(UP-1) hybrid proteins, indicating that antagonists are capable of stimulating PR dimerization in cells and do not function by disrupting or preventing dimerization. To determine whether PR bound to an antagonist can dimerize in whole cells with PR bound to agonist, GAL4/PR(UP-1) was paired in the two- hybrid assay with a VP16/PR fusion protein harboring a point mutation in PR at amino acid 722 (Gly-Cys) that specifically binds progestin agonist but not antagonist. Neither R5020 nor RU486 alone stimulated interaction between these ligand-specific PR hybrid proteins. However, strong interaction was detected by addition of both agonist and antagonists, indicating the formation of mixed ligand heterodimers and that both PR partners require ligand for dimerization to occur. Based on electrophoretic gel mobility shift assays (EMSAs), these heterodimers appear to have substantially reduced DNA binding activity. Progestin antagonists inhibit agonist activation of PR at concentrations that are too low to be accounted for by a simple competition mechanism for binding to PR. We propose that antiprogestin inactivation of PR in trans by heterodimerization contributes to the biological potency of these compounds.
Divergent Pathways Regulate Ligand-Independent Activation of ERα in SK-N-BE Neuroblastoma and COS-1 Renal Carcinoma Cells
Authors: Patrone Cesare , Gianazza Elisabetta , Santagati Sabrina , Agrati Paola , Maggi Adriana
Published: January 2014

The α-estrogen receptor (ERα) transcriptional activity can be regulated either by binding to the cognate ligand or by intracellular signaling pathways responsive to a variety of factors acting through cell membrane receptors. Studies carried out in HeLa and COS-1 cells demonstrated that the cross-coupling between estrogen and growth factor receptors is mediated by p21ras and requires phosphorylation of a specific serine residue (Ser 118 in the human ERα and Ser 122 in mouse ERα) located in the ERα N-terminal activation function 1 (AF-1). Likewise, in the SK-N-BE neuroblastoma cell line p21ras is involved in the cross-coupling between insulin and ERα receptors. However, in this cell line Ser 122 is not necessary for insulin-dependent activation of unliganded ERα. In addition, after insulin activation, the electrophoretic mobility associated to serine hyperphosphorylation of ERα in SK-N-BE and in COS-1 cells is different. Our study rules out the possibility of tyrosine phosporylation in unliganded ERα activation by means of transactivation studies of ERα tyrosine mutants and analysis of Tyr phosphorylation immunoreactivity. The two cofactors for steroid receptors RIP 140 and SRC-1 do not seem to be specifically involved in the insulin-induced ERα transactivation. The present study demonstrates the possibility of an alternative, cell-specific pathway of cross-coupling between intracellular and membrane receptors, which might be of importance for the understanding of the physiological significance of this mode of activation in the nervous system.
Differential Localization and Activity of the A- and B-Forms of the Human Progesterone Receptor Using Green Fluorescent Protein Chimeras
Authors: Lim Carol S. , Baumann Christopher T. , Htun Han , Xian Wenjuan , Irie Masako , Smith Catharine L. , Hager Gordon L.
Published: January 2014

Subcellular localization and transcriptional activity of green fluorescent protein-progesterone receptor A and B chimeras (GFP-PRA and GFP-PRB) were examined in living mammalian cells. Both GFP-PRA and B chimeras were found to be similar in transcriptional activity compared with their non-GFP counterparts. GFP-PRA and PRA were both weakly active, while GFP-PRB and PRB gave a 20- to 40-fold induction using a reporter gene containing the full-length mouse mammary tumor virus long-terminal repeat linked to the luciferase gene (pLTRluc). Using fluorescence microscopy, nuclear/cytoplasmic distributions for the unliganded and hormone activated forms of GFP-PRA and GFP-PRB were characterized. The two forms of the receptor were found to have distinct intracellular distributions; GFP-PRA was found to be more nuclear than GFP-PRB in four cell lines examined. The causes for and implications of this differential localization of the A and B forms of the human PR are discussed.
Tumor Necrosis Factor α-Mediated Insulin Resistance, but Not Dedifferentiation, Is Abrogated by MEK1/2 Inhibitors in 3T3-L1 Adipocytes
Authors: Engelman Jeffrey A. , Berg Anders H. , Lewis Renée Y. , Lisanti Michael P. , Scherer Philipp E.
Published: January 2014

Tumor necrosis factor-α (TNFα) has been implicated as a contributing mediator of insulin resistance observed in pathophysiological conditions such as obesity, cancer-induced cachexia, and bacterial infections. Previous studies have demonstrated that TNFα confers insulin resistance by promoting phosphorylation of serine residues on insulin receptor substrate 1 (IRS-1), thereby diminishing subsequent insulin-induced tyrosine phosphorylation of IRS-1. However, little is known about which signaling molecules are involved in this process in adipocytes and about the temporal sequence of events that ultimately leads to TNFα-stimulated IRS-1 serine phosphorylation. In this study, we demonstrate that specific inhibitors of the MAP kinase kinase (MEK)1/2-p42/44 mitogen-activated protein (MAP) kinase pathway restore insulin signaling to normal levels despite the presence of TNFα. Additional experiments show that MEK1/2 activity is required for TNFα-induced IRS-1 serine phosphorylation, thereby suggesting a mechanism by which these inhibitors restore insulin signaling.

We observe that TNFα requires 2.5–4 h to markedly reduce insulin-triggered tyrosine phosphorylation of IRS-1 in 3T3-L1 adipocytes. Although TNFα activates p42/44 MAP kinase, maximal stimulation is observed within 10–30 min. To our surprise, p42/44 activity returns to basal levels well before IRS-1 serine phosphorylation and insulin resistance are observed. These activation kinetics suggest a mechanism of p42/44 action more complicated than a direct phosphorylation of IRS-1 triggered by the early spike of TNFα-induced p42/44 activity.

Chronic TNFα treatment (≫ 72 h) causes adipocyte dedifferentiation, as evidenced by the loss of triglycerides and down-regulation of adipocyte-specific markers. We observe that this longer term TNFα-mediated dedifferentiation effect utilizes alternative, p42/44 MAP kinase-independent intracellular pathways.

This study suggests that TNFα-mediated insulin resistance, but not adipocyte dedifferentiation, is mediated by the MEK1/2-p42/44 MAP kinase pathway.
Thyroid Hormone-Responsive Pituitary Hyperplasia Independent of Somatostatin Receptor 2
Authors: Brinkmeier Michelle L. , Stahl Justin H. , Gordon David F. , Ross Brian D. , Sarapura Virginia D. , Dowding Janet M. , Kendall Susan K. , Lloyd Ricardo V. , Ridgway E. Chester , Camper Sally A.
Published: January 2014

Mice homozygous for the targeted disruption of the glycoprotein hormone α-subunit (αGsu) display hypertrophy and hyperplasia of the anterior pituitary thyrotropes. Thyrotrope hyperplasia results in tumors in aged αGsu−/− mice. These adenomatous pituitaries can grow independently as intrascapular transplants in hypothyroid mice, suggesting that they have progressed beyond simple hyperplasia. We used magnetic resonance imaging to follow the growth and regression of thyrotrope adenomatous hyperplasia in response to thyroid hormone treatment and discovered that the tumors retain thyroid hormone responsiveness. Somatostatin (SMST) and its diverse receptors have been implicated in cell proliferation and tumorigenesis. To test the involvement of SMST receptor 2 (SMSTR2) in pituitary tumor progression and thyroid hormone responsiveness in αGsu−/− mutants, we generated Smstr2−/−, αGsu−/− mice. Smstr2−/−, αGsu−/− mice develop hyperplasia of thyrotropes, similar to αGsu−/− mutants, demonstrating that SMSTR2 is dispensable for the development of pituitary adenomatous hyperplasia. Thyrotrope hyperplasia in Smstr2−/−, αGsu−/− mice regresses in response to T4 treatment, suggesting that SMSTR2 is not required in the T4 feedback loop regulating TSH secretion.
Differential Subcellular Distribution and Transcriptional Activity of ΣE3, ΣE4, and ΣE3–4 Isoforms of the Rat Estrogen Receptor-α
Authors: Pasqualini Catherine , Guivarc’h Dominique , Barnier Jean-Vianney , Guibert Bernard , Vincent Jean-Didier , Vernier Philippe
Published: January 2014

ΣE3, ΣE4, and ΣE3–4 are naturally occurring estrogen receptor (ER) isoforms, generated through differential splicing of the ERα primary transcript and abundantly expressed in embryonic rat pituitary. Studies in COS cells transfected with full-length ERα or its three splice variants fused to green fluorescent protein (GFP), revealed a different subcellular localization for each isoform. In the absence of estradiol, full-length ERα-GFP was predominantly nuclear, and ΣE3-GFP and ΣE4-GFP were present both in cytoplasm and nucleus, whereas ΣE3–4-GFP was predominantly cytoplasmic. Upon hormone treatment, a dramatic redistribution of full-length ERα-GFP and ΣE3-GFP, from a diffuse to punctate pattern, occurred within the nucleus. In contrast, the distribution of ΣE4-GFP and ΣE3–4-GFP was unaffected. Nuclear fractionation studies showed that full-length ER-α and ΣE3 displayed the same hormone-induced ability to tether to nuclear matrix, whereas nuclear ΣE4 appeared to remain loosely associated to functional nuclear constituents. When cotransfected with an estrogen-inducible reporter plasmid (VIT-TK-CAT) in ER-negative (CHO k1) and ER-positive pituitary (GH4 C1) cells, ΣE3–4 exhibited a very weak estrogen-dependent transactivation activity, whereas ΣE3 had an inhibitory effect on full-length ER action. Conversely, ΣE4 displayed estrogen-independent transcriptional activity in ER-negative cells, and in ER-positive cells, enhanced the estrogen-induced gene expression as efficiently as full-length ERα. In a gel mobility shift assay, phosphorylated ΣE4 was able to form a specific complex with a consensus ERE, while ΣE3 and ΣE3–4 never did bind by themselves. The observed inhibitory action of ΣE3 on estrogen-dependent transcription would rather involve protein-protein interactions such as formation of heterodimers with full-length ERα, as suggested by immunoprecipitation followed by Western blotting. These data suggest that ΣE3 and ΣE4 may play a physiologically relevant role as negative or constitutively positive modulators of transcription, in the developing rat pituitary.
AR Suppresses Transcription of the α Glycoprotein Hormone Subunit Gene Through Protein-Protein Interactions with cJun and Activation Transcription Factor 2
Authors: Jorgensen Joan S. , Nilson John H.
Published: January 2014

Previously, we reported that the AR directly suppressed transcription of the α glycoprotein hormone subunit (αGSU) gene in a ligand-dependent fashion while ER had no effect. Mutagenesis studies of the αGSU promoter indicated that two elements were required for AR-mediated suppression: the α basal element and tandem cAMP response elements (CREs). Because several members of the bZip family of transcriptional proteins can bind the CREs, we used several functional assays to determine whether AR interacts selectively with cJun, activation transcription factor 2 (ATF2), or CRE binding protein (CREB). When tested by cotransfection with AR, cJun and ATF2 specifically rescued androgen-mediated suppression of theα GSU-reporter construct in a gonadotrope-derived cell line. In contrast, cotransfected CREB displayed no activity in this rescue assay. In fact, overexpression of CREB alone diminished activity of theα GSU promoter, suggesting that the transcriptional activity normally conferred by the tandem CREs in gonadotropes requires their occupancy by cJun/ATF2 heterodimers. Binding assays carried out with a glutathione-S-transferase-AR fusion protein indicated that the receptor itself also displayed a clear preference for binding cJun and ATF2. Furthermore, we ruled out the possibility that AR suppressed activity of the αGSU promoter by reducing synthesis of these bZip proteins. Additional experiments suggested that phosphorylation of AR or histone acetylation are unlikely requirements for AR suppression of αGSU promoter activity. Thus, our data suggest that AR suppresses activity of the αGSU promoter through direct protein-protein interactions with cJun and ATF2.
Calmodulin Is a Selective Modulator of Estrogen Receptors
Authors: García Pedrero Juana M. , del Rio Beatríz , Martínez-Campa Carlos , Muramatsu Masami , Lazo Pedro S. , Ramos Sofía
Published: January 2014

In the search for differences between ERα and ERβ, we analyzed the interaction of both receptors with calmodulin (CaM) and demonstrated that ERα but not ERβ directly interacts with CaM. Using transiently transfected HeLa cells, we examined the effect of the CaM antagonist N-(6-aminohexyl)-5-chloro-naphthalene sulfonilamide hydrochloride (W7) on the transactivation properties of ERα and ERβ in promoters containing either estrogen response elements or activator protein 1 elements. Transactivation by ERα was dose-dependently inhibited by W7, whereas that of ERβ was not inhibited or even activated at low W7 concentrations. In agreement with these results, transactivation of an estrogen response element containing promoter in MCF-7 cells (which express a high ERα/ERβ ratio) was also inhibited by W7. In contrast, transactivation in T47D cells (which express a low ERα/ERβ ratio) was not affected by this CaM antagonist. The sensitivity of MCF-7 cells to W7 was abolished when cells were transfected with increasing amounts of ERβ, indicating that the sensitivity to CaM antagonists of estrogen-responsive tissues correlates with a high ERα/ERβ ratio. Finally, substitution of lysine residues 302 and 303 of ERα for glycine rendered a mutant ERα unable to interact with CaM whose transactivation activity became insensitive to W7. Our results indicate that CaM antagonists are selective modulators of ER able to inhibit ERα-mediated activity, whereas ERβ actions were not affected or even potentiated by W7.
Growth Enhancement in Suppressor of Cytokine Signaling 2 (SOCS-2)-Deficient Mice Is Dependent on Signal Transducer and Activator of Transcription 5b (STAT5b)
Authors: Greenhalgh Christopher J. , Bertolino Patrick , Asa Sylvia L. , Metcalf Donald , Corbin Jason E. , Adams Timothy E. , Davey Helen W. , Nicola Nicos A. , Hilton Douglas J. , Alexander Warren S.
Published: January 2014

Mice lacking suppressor of cytokine signaling-2 (SOCS-2) exhibit accelerated postnatal growth resulting in adult mice that are 1.3 to 1.5 times the size of normal mice. In this study we examined the somatotrophic pathway to determine whether the production or actions of GH or IGF-I are altered in these mice. We demonstrated that SOCS-2−/− mice do not have elevated GH levels and suffer no major pituitary dysmorphogenesis, and that SOCS-2-deficient embryonic fibroblasts do not have altered IGF-I signaling. Primary hepatocytes from SOCS-2−/− mice, however, did have moderately prolonged signal transducer and activator of transcription 5 signaling in response to GH stimulation. Furthermore, the deletion of SOCS-2 from mice also lacking signal transducer and activator of transcription 5b had little effect on growth, suggesting that the action of SOCS-2 may be the regulation of the GH signaling pathway.
Semiotics and interdisciplinarity: Lotman’s legacy
Authors: Gherlone Laura
Published: January 2014

A particular aspect of Juri Lotman’s semiotic theory is, without a doubt, the acknowledgment of the impossibility of adopting a single scientific language for the comprehension of processes underlying cultural dynamics. In his last work, Unpredictable Mechanisms of Culture, Lotman underscores that natural sciences and humanities have to search for the unity of the incompatible through a profound meta-linguistic dialogue. Th is can happen only considering the reality in its antinomies, or as informed by a plurality of languages reciprocally aimed to express the real movement of objects – a heterogeneous and contradictory movement: hence, Lotman’s suggestion (which is also his ethical legacy) that the Aristotelian polyhedral unity of science be returned to. The aim of this paper is to retrace Lotman’s relationship with the ideas of science, scientificity and interdisciplinary method, stressing his last reflections concerning the urgency of returning to the Aristotelian unified structure of knowledge, or a form of knowledge in which different and never completely mutually translatable scientific languages coexist autonomously, while being in a dialogue.
Mixing signs and bones: John Deely’s case for global semiosis
Authors: Petrov Petre
Published: January 2014

The article develops a critique of John Deely’s ontological realism, specifically in its relevance for the project of global semiotics. Deely, whose theorizations rely heavily on the pre-modern philosophical systems of Thomas Aquinas and the Latin scholastics, has made the most sustained attempt to give philosophical grounding to Charles Peirce’s famous intuition that “all this universe is perfused with signs, if it is not composed exclusively of signs”. The critique develops along two main lines. Firstly, I contend that Deely’s account of ontological relations is unsatisfactory, for it assumes the very fact it promises to demonstrate: the identity between patterns of physical events, on one hand, and patterns of thought, on the other. As it is never adequately explained what it means for the former to be identical with the latter, the mediating term – “ontological relation” – remains highly problematic. Secondly, I argue that even if this ontological paradigm is allowed to stand as proposed, it still fails to bridge the gap between the so-called “natural” signs and human-specific, language-based signification; for, as it posits a unity between the stipulable and the non-stipulable sign, the argument falls into a performative contradiction.
Peircean semiotics in the context of design praxis: Abduction and perception in dialogue
Authors: Rampazzo Gambarato Renira
Published: January 2014

This paper discusses design process as a creative activity along with conceptual correlations of the semiotics developed by Charles Sanders Peirce. The central aim of this paper is to examine one of the most important concepts in Peirce’s theory related to design praxis: the concept of abduction. Abduction is the driving force behind creation and a way of producing new ideas. Peirce’s original concept is fundamental in order to maintain constant commitment to innovation required by design. To transmit messages in a creative way it is more efficient to intensely work with associations by similarity in order to obtain signs rich in information and analogies. Design communicates by all its constituent elements: shape, function, colour, material, technique, technology, etc. Therefore, signs of design share peculiar values of artistic signs as well as those of communicative ones. The associated information is as much aesthetic (shape) as it is semantic (content). The appropriation of Peircean concepts contributes to the understanding of the creative process, which in turn is crucial for understanding new possibilities by means of design.
The two pragmatisms in the philosophy of Ivan Sarailiev
Authors: Tashev Andrey
Published: January 2014

This article focuses on the views held by the early Bulgarian representative and interpreter of pragmatism Ivan Sarailiev (1887–1969) on the two trends of this doctrine – the method for ascertaining meaning proposed by Charles Sanders Peirce, and the theory of truth propounded by William James. Sarailiev applied and propagated the pragmatist ideas of the doctrine’s founders in Bulgaria in the 1920s, and is thus one of the first followers of Peirce in Europe and the very first in Eastern Europe. How deep was Sarailiev’s understanding of the two types of pragmatism? How did they shape his philosophy and what was their role? This article will try to address these questions as well as presenting the overall reception of pragmatism in Bulgaria in the Interwar period through Sarailiev who was its only serious proponent both at the time and long afterwards.
Augustine on lying: A theoretical framework for the study of types of falsehood
Authors: Gramigna Remo
Published: January 2014

This paper presents a theoretical investigation of the issue of lying from a semiotic perspective and its specific aim is the analysis of the theory of the lie as conceived by Aurelius Augustinus, bishop of Hippo (354–430 A.D.), also known as Augustine or St. Augustine. The latter devoted two short treatises to the issue of lying: De mendacio (On lying) and Contra mendacium (Against lying), written in ca. 395 DC and 420 DC, respectively. The paper will focus on duplicity and intention to deceive as fundamental and necessary features of the lie. Augustine’s chief contribution to the study of human deception was to have severed the assessment of what is a lie from factual falsity. For Augustine, at the kernel of the notion of lying lies the idea of intentionality. Following this line of thought, the paper singles out two types of intentionality, namely the intention to assert a falsehood and the intention to mislead. On the basis of this double nature of intentionality, the present paper seeks to outline a theoretical framework for the study of species of falsehoods. The outcome is a typology of untruthfulness that envisages a fourfold inventory of falsehoods based on the difference between jokes, errors, lies and pretences.
Man, nature, and semiotic modelling or How to create forests and backyards with language
Authors: Augustyn Prisca
Published: January 2014

This paper explains how we create concepts such as the forest or the backyard through language. Reflecting on Andreas Weber’s hope for a revolution of the life sciences and a re-evaluation of the role human beings play in nature, this paper adopts as a starting point Bruno Latour’s characterization of the distinction between nature and culture as an illusion that came with Modernity. Theoretical notions from modelling systems theory and cognitive linguistics explain that while language plays a key role in constructing new models of nature, new cognitive habits and changes of belief depend on face-to-face and non-verbal communication with other organisms, human and non-human.
Approaching a semiotics of exaptation: At the intersection between biological evolution and technological development
Authors: Weible Davide
Published: January 2014

This paper recognizes a specific correspondence between biological evolution and technological development and on this basis tries to set up a semiotic approach to the evolutionary phenomenon of exaptation. To do this, the existence of a historical-structural and pragmatic analogy between organs and tools is shown, which in turn implies on a communicative ground the dissolution of some of their traditional distinctive attributes. Finally, a philosophical-analytical approach to natural and cultural functions is applied to define three types of exaptations.
Lotman’s tradition: Semiotics of culture from a Latin American perspective
Authors: Gómez Ponce Ariel
Published: January 2014

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The Dolichopus plumipes species group (Diptera, Dolichopodidae) in the Palaearctic Region with the description of a new species from Iran
Authors: Khaghaninia Samad , Gharajedaghi Yaser , Grichanov Igor Ya.
Published: January 2014

The Dolichopus plumipes species group in the Palaearctic Region is redefined. It comprises eleven species including one new species, Dolichopus malekii sp. nov., from the East Azerbaijan province in north-western Iran. The species group is differentiated from other Dolichopus by the modified male mid tibia and/or mid basitarsus (except D. simplex). The mid tibia is often thin, having a longitudinal narrow dark streak (D. plumipes) or clear whitish yellow dorsal area in distal third, rarely simple or inconspicuously modified (D. discifer). Mid basitarsus is pennate or bearing elongate setae or simple. Other tarsomeres are usually simple (except D. discifer). A revised key to the species group is provided, as well as remarks on its geographical distribution.
Synthesis and antitubercular evaluation of aryl substituted 2-oxazolines from L-amino acids
Authors: De Souza Leidiane Araujo , Da Silva Emerson Teixeira , Lourenço Maria Cristina Silva , De Souza Marcus Vini­cius Nora
Published: January 2014

This paper describes the synthesis and the in vitro antibacterial activity of a series of twelve substituted aryl-2-oxazolines against Mycobacterium tuberculosis. Seven compounds showed activity and two compounds exhibited a minimal inhibitory concentration (MIC) of 25 ï­g/mL were not cytotoxic for the host cells in cell viability assay. These results could be a good starting point for the development of new antitubercular lead series based on this family of compounds.
Sandwich Assay for Tacrolimus Using 2 Antitacrolimus Antibodies
Authors: Wei Tie Q , Zheng Yi F , Dubowy Michael , Sharma Manoj
Published: January 2014

BACKGROUND

Although detection of natural haptens by antihapten antibodies in sandwich assay format has the theoretical advantages of high analytical specificity and sensitivity, this type of assay has not been reported because of the seemingly insurmountable task of avoiding steric hindrance between the 2 bindings. This is especially true for ring-structured hydrophobic haptens. The macrolide drug tacrolimus (FK506, Prograf®, 804 Da) is such a hapten. Here we show the detection of tacrolimus using 2 antitacrolimus monoclonal antibodies in a sandwich assay.

METHODS

Both antibodies were developed by use of an intact tacrolimus molecule covalently linked to a carrier protein but via 2 different positions separated by 10 carbon atoms. Epitope analysis based on drug analog binding was used to show no overlap between the binding sites of the 2 antibodies, indicating the 10-carbon separation resulted in 2 distinct epitopes. The distinct epitopes suggested that the drug might be approachable by the antibodies from 2 separate directions, which predicted simultaneous binding as in sandwich formation.

RESULTS

This prediction was confirmed in sandwich ELISA and affinity column–mediated immunoassay formats. The assay demonstrated good imprecision and significantly lower metabolite cross-reactivity than competitive assay counterparts. Comparison with liquid chromatography–tandem mass spectrometry (LC-MS/MS) using 55 whole-blood samples from transplant patients with tacrolimus concentrations ranging from 0.9 to 29.5 ng/mL showed a linear regression: sandwich = 0.99 × LC-MS/MS + 0.10 ng/mL, r = 0.991, Sy|x = 1.08 ng/mL.

CONCLUSIONS

This work demonstrates that a highly specific sandwich assay using 2 antihapten antibodies is feasible for the measurement of a hapten drug.
Publication and Reporting of Test Accuracy Studies Registered in ClinicalTrials.gov
Authors: Korevaar Daniël A , Ochodo Eleanor A , Bossuyt Patrick M M , Hooft Lotty
Published: January 2014

BACKGROUND

Failure to publish and selective reporting are recognized problems in the biomedical literature, but their extent in the field of diagnostic testing is unknown. We aimed to identify nonpublication and discrepancies between registered records and publications among registered test accuracy studies.

METHODS

We identified studies evaluating a test's accuracy against a reference standard that were registered in ClinicalTrials.gov between January 2006 and December 2010. We included studies if their completion date was set before October 2011, allowing at least 18 months until publication. We searched PubMed, EMBASE, and Web of Science and contacted investigators for publications.

RESULTS

We included 418 studies, of which 224 (54%) had been published by mid-2013. Among studies that had been completed at least 30 months before our analyses, 45% were published within 30 months after their completion. Publication rates were high in studies registered after study completion (76%) and low for studies with an unknown (rather than completed) study status (36%). After we excluded these 2 categories, study duration was the only characteristic significantly associated with publication, with lower rates in studies lasting up to 1 year (39%) compared to studies of 13–24 months (62%) or longer (67%) (P = 0.01). In the 153 published studies that had been registered before completion, 49 (32%) showed discrepancies between the registry and publication regarding inclusion criteria (n = 19), test/threshold (n = 9), and outcomes (n = 32).

CONCLUSIONS

Failure to publish and selective reporting are prevalent in test accuracy studies. Their registration should be further promoted among researchers and journal editors.
Mutant LRRK2 Toxicity in Neurons Depends on LRRK2 Levels and Synuclein But Not Kinase Activity or Inclusion Bodies
Authors: Skibinski Gaia , Nakamura Ken , Cookson Mark R. , Finkbeiner Steven
Published: January 2014

By combining experimental neuron models and mathematical tools, we developed a “systems” approach to deconvolve cellular mechanisms of neurodegeneration underlying the most common known cause of Parkinson's disease (PD), mutations in leucine-rich repeat kinase 2 (LRRK2). Neurons ectopically expressing mutant LRRK2 formed inclusion bodies (IBs), retracted neurites, accumulated synuclein, and died prematurely, recapitulating key features of PD. Degeneration was predicted from the levels of diffuse mutant LRRK2 that each neuron contained, but IB formation was neither necessary nor sufficient for death. Genetic or pharmacological blockade of its kinase activity destabilized LRRK2 and lowered its levels enough to account for the moderate reduction in LRRK2 toxicity that ensued. By contrast, targeting synuclein, including neurons made from PD patient-derived induced pluripotent cells, dramatically reduced LRRK2-dependent neurodegeneration and LRRK2 levels. These findings suggest that LRRK2 levels are more important than kinase activity per se in predicting toxicity and implicate synuclein as a major mediator of LRRK2-induced neurodegeneration.
Whole-Genome DNA Methylation Profile of the Jewel Wasp (Nasonia vitripennis)
Authors: Beeler Suzannah M , Wong Garrett T , Zheng Jennifer M , Bush Eliot C , Remnant Emily J , Oldroyd Benjamin P , Drewell Robert A
Published: January 2014

The epigenetic mark of DNA methylation, the addition of a methyl (CH3) group to a cytosine residue, has been extensively studied in many mammalian genomes and, although it is commonly found at the promoter regions of genes, it is also involved in a number of different biological functions. In other complex animals, such as social insects, DNA methylation has been determined to be involved in caste differentiation and to occur primarily in gene bodies. The role of methylation in nonsocial insects, however, has not yet been explored thoroughly. Here, we present the whole-genome DNA methylation profile of the nonsocial hymenopteran, the jewel wasp (Nasonia vitripennis). From high-throughput sequencing of bisulfite-converted gDNA extracted from male Nasonia thoraces, we were able to determine which cytosine residues are methylated in the entire genome. We found that an overwhelming majority of methylated sites (99.7%) occur at cytosines followed by a guanine in the 3′ direction (CpG sites). Additionally, we found that a majority of methylation in Nasonia occurs within exonic regions of the genome (more than 62%). Overall, methylation is sparse in Nasonia, occurring only at 0.18% of all sites and at 0.63% of CpGs. Our analysis of the Nasonia methylome revealed that in contrast to the methylation profile typically seen in mammals, methylation is sparse and is constrained primarily to exons. This methylation profile is more similar to that of the social hymenopteran species, the honey bee (Apis mellifera). In presenting the Nasonia methylome, we hope to promote future investigation of the regulatory function of DNA methylation in both social and nonsocial hymenoptera.