bluuebunny/crossref_metadata_2025_split huggingface dataset:
Production of live offspring with predicted genotypes using PCR‐RFLP analysis of polar bodies from mouse oocytes
Authors: Wheeler M. B. , Noble J. A. , Jarrell V. L. 
Published: February 2005

AbstractAccurate identification of genotypes in gametes and early embryos could facilitate the efficient production of offspring with desirable traits. This study demonstrates the feasibility of producing offspring with predictable genotypes from micromanipulated mouse oocytes. The Polymerase Chain Reaction (PCR) was used to amplify genes in the IA subregion of the major histocompatibility complex of the mouse. The validity of the approach was demonstrated in experiment 1 with IA haplo‐types of unfertilized mouse ova amplified via PCR and distinguished by restriction fragment length polymorphism (RFLP) analysis. In experiment 2, fertilized oocytes were micromanipulated to remove the first and second polar bodies, which were then genotyped by validated PCR‐RFLP procedures. Primary oocytes of heterozygous females contain two copies of each of the different alleles. Following meiosis I and II, the genotype of the ovum was predicted by subtracting the alleles observed in micromanipulated polar body samples. Sixty‐two fertilized ova were micromanipulated and transferred to recipient females resulting in 27 live offspring (44%). The correct maternal contribution to the embryonic genotype was predicted in 19 of 27 (71%) offspring as confirmed by PCR‐RFLP analysis of DNA from pup tails. Predicted genotypes of two pups were not confirmed (7%), whereas no prediction could be made in six cases (22%). © 1995 Wiley‐Liss, Inc.
Initial culture behaviour of rat blastocysts on selected feeder cell lines
Authors: Ouhibi Nadia , Sullivan Neil F. , English Jennifer , Colledge William H. , Evans Martin J. , Clarke Neil J. 
Published: February 2005

AbstractTo increase our understanding of rat embryos in culture and to attempt the isolation of blastocyst‐derived cell lines, we examinated the initial growth behaviour of rat blastocysts from four strains of rat on four different feeder cell layers. The feeders used were a continuous cell line of murine embryonic fibroblasts (STO), primary mouse (MEF) or primary rat (REF) embryonic fibroblasts, and a continuous cell line of rat uterine epithelial cells (RUCs). A medium that gave optimum plating efficiencies for murine ES cells was used in the rat embryo culture. Each culture system allowed hatching and attachment of the blastocysts, that is, the behaviour was similar on each feeder and each strain for the first 2 days in culture. Subsequently, there was a rapid differentiation of the Inner Cell Mass (ICM) cells on fibroblastic feeder cell layers (STO > MEF > REF), and this was generally complete after 3–6 days in primary culture. On RUCs, the ICM was found to increase in size without differentiation up to and including day 4 and in some cases longer. Embryo‐derived cells were obtained by disaggregating and passaging ICMs on REF and RUC feeders. Rounded, refractile, and epithelial‐like cells were isolated on REF and colonies of ES‐like cells on the RUCs. The ES‐like cells were positive for expression of alkaline phosphatase and stage‐specific embryonic‐antigen 1. This is an important first step towards the derivation and culture of pluripotent ES cells from the rat. © 1995 Wiley‐Liss, Inc.
DNA Synthesis and pronucleus development in pig zygotes obtained in vivo: An autoradiographic and ultrastructural study
Authors: Laurnick J. , Hyttel P. , Kopecny V. 
Published: February 2005

AbstractPorcine zygotes flushed from oviducts 48,52,56,60, or 64 hr after hCG were incubated 30 min in 3H‐thymidine, transferred to nonradioactive medium for 2 hr, and incubated for 30 min with 14C‐thymidine. After this procedure, ova were prepared (i.e., at 51,55,59,63, or 67 hr after hCG) for autoradiography and ultrastructural observations, respectively.The first autoradiographic labelling, i.e., DNA synthesis, was observed at 56–56.5 hr after hCG, while the latest labelling was seen at 60–60.5 hr.At 51 hr after hCG, formation of the pronuclear envelope was observed, while no nucieolus precursor bodies or prestages to these structures were found. At 55 hr a few clusters of small electron‐dense granules were observed, together with condensed chromatin in the pronuclei. At 59 hr the apposed regions of both pronuclei contained nucleolus precursor bodies and condensed chromatin, in close contact with both clusters of small granules and clusters of an additional category of large granules and the nuclear envelope. Additionally, large accumulations of the small granules were found in the vicinity of similarly sized accumulations of the large granules without chromatin association. At 63 hr the spherical accumulations large granules on some occasions presented a central vacuole, and condensed chromatin and clusters of small granules were attached to its periphery. Within the vacuole, electrondense material was found.It is concluded that (1) the S‐phase in porcine zygotes is initiated around 56 hr post‐hCG injection and is of a duration of 4.5–7.5 hr and (2) the progress of the S‐phase is paralleled by the appearance of and complex interaction between different granules in the nucleoplasm. © 1995 Wiley‐Liss, Inc.
PRINS as a method for rapid chromosomal labeling on human spermatozoa
Authors: Pellestor Franck , Girardet Anne , Lefort Geneviève , Andréo Brigitte , Charlieu Jean Paul 
Published: February 2005

AbstractDirect in situ labeling of human spermatozoa was performed using the PRINS method. This technique is based on annealing of specific oligonucleotide primers, and subsequent primer extension by a Taq DNA polymerase. The reaction was carried out on a programmable temperature cycler, and labeling was obtained in a 1‐hr reaction. The method was successfully tested with specific primers for chromosomes 13, 16, and 21. This suggests that PRINS may be a fast and reliable technique for detecting aneuploidies. © 1995 Wiley‐Liss Inc.
Identification of heterotrimeric G proteins in human sperm tail membranes
Authors: Hinsch Klaus‐Dieter , Schwerdel Carola , Habermann Barbara , Schill Wolf‐Bernhard , Müller‐Schlösser F. , Hinsch Elvira 
Published: February 2005

AbstractHeterotrimeric G proteins play important roles as signal transducing components in various mammalian sperm functions. We were interested in the distribution of G proteins in human sperm tails. Prior to membrane preparation, spermatozoa were separated from contaminating cells which are frequently present in human ejaculates. Enriched human sperm tail membranes were generated by using hypoosmotic swelling and homogenization procedures. Antisera against synthetic peptides were used to identify G proteins in immunoblots. AS 8, an antiserum directed against an amino acid sequence that is found in most G protein α‐subunits, and A 86, which detects all known pertussis toxin‐sensitive α‐subunits, reacted specifically with a 40‐kDa protein. Antisera against individual G protein α‐subunits failed to detect any specific antigens in enriched tail membranes AS 36, recognizing the ã2‐subunit of G proteins, identified a 35‐kDa protein in sperm tail membranes. Antisera against the 36‐kDa β1‐subunit did not detect any relevant proteins in the membrane fraction. Neither G protein α‐subunits nor G protein β‐subunits were found in the cytosol. ADP ribosylation of spermatozoal membrane or cytosolic proteins revealed no pertussis toxin‐sensitive α‐subunits. However, membrane preparations of nonpurified human spermatozoa contained α2 subunits, as shown immunologically and by ADP ribosylation; they most probably derived from somatic cells which are frequently present in human ejaculates. Our results stress the fact that spermatozoa need to be purified before sperm membrane preparation to avoid misinterpretations caused by contaminating cells. Furthermore, we suggest that G proteins in membranes of human sperm tails belong to a novel subtype of G protein α‐subunits; the putative β‐subunit was identified as a β2‐subunit. © 1995 Wiley‐Liss, Inc.
Induction of paternal genome loss by the paternal‐sex‐ratio chromosome and cytoplasmic incompatibility bacteria (Wolbachia): A comparative study of early embryonic events
Authors: Reed Kent M. , Werren John H. 
Published: February 2005

AbstractPaternal genome loss (PGL) during early embryogenesis is caused by two different genetic elements in the parasitoid wasp, Nasonia vitripennis. Paternal sex ratio (PSR) is a paternally inherited supernumerary chromosome that disrupts condensation of the paternal chromosomes by the first mitotic division of fertilized eggs. Bacteria belonging to the genus Wolbachia are present in Nasonia eggs and also disrupt paternal chromosome condensation in crosses between cytoplasmically incompatible strains. Cytoplasmic incompatibility Wolbachia are widespread in insects, whereas PSR is specific to this wasp. PGL results in production of male progeny in Nasonia due to haplodiploid sex determination. The cytological events associated with PGL induced by the PSR chromosome and by Wolbachia were compared by fluorescent light microscopy using the fluorochrome Hoescht 33258. Cytological examination of eggs fertilized with PSR‐bearing sperm revealed that a dense paternal chromatin mass forms prior to the first metaphase. Quantification of chromatin by epifluorescence indicates that this mass does undergo replication along with the maternal chromatin prior to the first mitotic division but does not replicate during later mitotic cycles. Contrary to previous reports using other staining methods, the paternal chromatin mass remains condensed during interphase and persists over subsequent mitotic cycles, at least until formation of the syncytial blastoderm and cellularization, at which time it remains near the center of the egg with the yolk nuclei. Wolbachia‐induced PGL shows several marked differences. Most notable is that the paternal chromatin mass is more diffuse and tends to be fragmented during the first mitotic division, with portions becoming associated with the daughter nuclei. Nuclei containing portions of the paternal chromatin mass appear to be delayed in subsequent mitotic divisions relative to nuclei free of paternal chromatin. Crosses combining incompatibility with PSR were cytologically similar to Wolbachia‐induced PGL, although shearing of the paternal chromatin mass was reduced. Wolbachia may, therefore, block an earlier stage of paternal chromatin processing in the fertilized eggs than does PSR. © 1995 Wiley‐Liss, Inc.
Effect of genotype on the efficiency of mouse embryo cryopreservation by vitrification or slow freezing methods
Authors: Dinnyés A. , Wallace G. A. , Rall W. F. 
Published: February 2005

AbstractWe examined possible genotype effects on the survival of 8‐ to 16‐cell mouse embryos isolated from four inbred strains (C57BL/6N, BALB/cAnN, DBA/2N, and C3H/HeN), a outbred stock (ICR), and various crosses after cryopreservation by vitrification or conventional slow freezing using glycerol solutions. The rates of in vitro development of C57BL/6N, BALB/cAnN, C3H/HeN, and ICR embryos to expanded blastocysts ranged from 86% to 94% after slow freezing and 85% to 97% after vitrification. The cryopreservation method did not significantly influence in vitro embryo survival after thawing (P >0.05). Although genotype significantly influenced the in vitro survival of embryos (P = 0.008), this presumably resulted from an increased difficulty in assessing the quality grade of C3H/HeN embryos prior to cryopreservation. The rates in vivo development of C57BL/6N, BALB/cAnN, C3H/HeN, DBA/2N, and ICR embryos to normal day 18–19 fetuses ranged from 19% to 64% after slow freezing and from 18% to 63% after vitrification. The in vivo development of cryopreserved embryos was significantly influenced by cryopreservation method and genotype (P = 0.01 and P = 0.001, respectively). Vitrification yielded significantly higher rates of in vivo development than that after slow freezing (P > 0.05). In vivo development rates of DBA/2N and ICR♀ X B6D2F1 ♂ embryos after cryopreservation were significantly higher than that of embryos from BALB/cAnN and C3H/HeN mice (P < 0.05). These results indicate that parental genotype exerts little or no effect on the ability of embryos to develop in vitro after vitrification or slow freezing. Differences in the ability of cryopreserved embryos to develop normally in vivo may reflect inherent genotype related differences in their post‐implantation developmental potential and not their sensitivity to cryoinjury. © 1995 Wiley‐Liss, Inc.This article is a US Government work and, as such, is in the public domain in the United States of America.
IPEB transcription factor regulating the intracisternal a particle gene during F9 cell differentiation is expressed at sites of lymphoid development
Authors: Kamat Jaya P. , Basu Amitabha , Satyamoorthy Kapaettu , Xu Mei Q. , Showe Louise , Howe Chin C. 
Published: February 2005

AbstractThe murine intracisternal A particle (IAP) proviral elements are expressed at low levels in undifferentiated F9 embryonal carcinoma cells but are highly expressed when F9 cells are induced to differentiate into parietal endoderm‐like cells. IAP elements are also expressed in parietal endoderm‐like PYS‐2 cells. We previously identified an IAP proximal enhancer (IPE) element that mediates a F9 differentiation‐specific enhancer activity. We also identified a 60 kDa IPE binding (IPEB) protein whose activity is high in PYS‐2 cells, where IAP is expressed, but very low in F9 cells.Transcription of IAP elements has also been shown in the adult mouse thymus and in activated splenic B cells. We have now shown by DNA affinity chromatography, sodium dodecyl sulfate‐polyacrylamide gel electrophoresis, and band‐shift analysis that the 60 kDa IPEB is expressed in adult T lymphocytes and in resting as well as lipopolysaccharide activated splenic B cells but not in adult liver cells, suggesting an important role for IPEB in IAP transcription in vivo. In addition, we find IPEB expressed in the fetal mouse at sites of lymphoid development, such as the liver, spleen, and thymus, suggesting it may play an important role in gene expression during lymphoid development. In support of this, we find IPEB in the human T cell tumor lines, Jurkat and Molt 13, as well as the Daudi B cell line and in the normal calf thymus and in the thymus and spleen of the chicken and rat. © 1995 Wiley‐Liss, Inc.
Strain‐specific progression of α‐amanitin—treated mouse embryos beyond the two‐cell stage
Authors: Rambhatla Lakshmi , Latham Keith E. 
Published: February 2005

AbstractMouse embryos produced by the fertilization of eggs from (B6D2)F1 and CF‐1 mice differ in their ability to complete the second cell cycle in the presence of α‐amanitin. Essentially all embryos obtained from CF‐1 mothers arrest at the two‐cell stage when cultured from the late one‐cell stage in α‐amanitin at concentrations that prevent zygotic genome activation, while up to 15% of the embryos obtained from (B6D2)F1 mothers can progress to the three‐ to four‐cell stage. This occurs even at α‐amanitin concentrations that are fivefold greater than that required to prevent gene transcription. We propose that eggs of certain strains of mice may be endowed with greater supplies of macromolecules to support early development and that a percentage of these embryos can complete the second cell cycle in the absence of transcription. This difference may contribute to the strain‐dependent differences in development in vitro. © 1995 Wiley‐Liss, Inc.
Oocyte and follicular morphology as determining characteristics for developmental competence in bovine oocytes
Authors: Blondin Patrick , Sirard Marc‐André 
Published: February 2005

AbstractFollicular size, follicular atresia, and oocyte morphology were investigated for the possible relation of these characteristics to the developmental competence of bovine oocytes. Ovaries from a local slaughterhouse were dissected to obtain a heterogeneous population of follicles. Half of each follicle was fixed for histological analysis, and the oocytes were detached carefully and cultured individually. Before in vitro maturation, the oocytes were grouped into six different classes based on the morphology of the cumulus and the ooplasm: classes 1 and 2 represent oocytes with a homogeneous ooplasm plus a compact and complete cumulus, and classes 3–6 represent oocytes with a granulated ooplasm and an incomplete and/or expanded cumulus. Oocytes from class 3 (beginning of expansion in outer cumulus layers and slight granulations in the ooplasm) developed past the 16‐cell stage significantly (P<0.05) more than oocytes with a compact and complete cumulus (classes 1 and 2) and oocytes from classes 4–6 (incomplete and/or expanded cumulus) after 5 days of in vitro culture. Oocytes from follicles measuring 3 mm or less did not develop past the 16‐cell stage, whereas follicles of 3–5 mm and 5 mm or larger developed at similar rates (17% and 21% morulae, respectively). The state of the follicle did not affect whether an embryo reached at least the 16‐cell stage, as comparable rates were obtained in all three groups of follicles: nonatretic (20%), intermediate (14%), and slightly atretic (16%). We concluded that oocytes acquire developmental competence late in the follicular phase, possibly when the first signs of atresia have appeared, and that oocytes with beginning signs of degeneration (class 3) will develop significantly more than all other classes. Class 3 oocytes originated from follicles that were generally atretic and therefore in later phases of follicular growth, suggesting that these oocytes, having been subjected longer to the follicular microenvironment, are more differentiated (possibly at the cytoplasmic level) than other classes of oocytes. © 1995 Wiley‐Liss, Inc.
Ultrastructural localization of acrosome reaction‐inducing substance (ARIS) on sperm of the starfish Asterias amurensis
Authors: Longo Frank J. , Ushiyama Akira , Chiba Kazuyoshi , Hoshi Motonori 
Published: February 2005

AbstractUsing colloidal gold tagged ligands we have identified the ultrastructural site of ARIS binding to intact and acrosome‐reacted starfish sperm. In intact sperm, colloidal gold conjugated ARIS was specifically localized to a single domain (0.1–0.3μ in diameter) on the plasma membrane. This site was located on the anterior‐lateral aspect of the sperm head, that is, just peripheral to the region occupied by the acrosomal vesicle and periacrosomal components. When sperm were labeled with colloidal gold conjugated ARIS, washed to remove unbound label, and then induced to undergo the acrosome reaction, the labeled patch remained associated with the plasma membrane and was positioned just lateral to the acrosomal process. However, when sperm were suspended in labeled ARIS and induced to undergo the acrosome reaction, label was observed along the entire anterior aspect of the sperm head with the exception of the acrosomal process. Labeling along the entire anterior aspect of the sperm head in this case was deemed to be nonspecific and due to binding of colloidal gold tagged molecules to components formerly located within the acrosomal vesicle, as the same pattern was obtained using colloidal gold tagged bovine serum albumin. Quantitative and qualitative aspects of ARIS binding observed here by electron microscopy are in agreement with measured binding characteristics previously reported (Ushiyama et al., 1993a: Zygote 1:121–127; Ushiyama et al., 1993b: J Reprod Dev 39:53–54), and indicate that the site of labeled ARIS binding represents a specific plasma membrane domain occupied by ARIS receptors. © 1995 Wiley‐Liss, Inc.
Cloning of a novel rat placental prolactin‐like protein C‐related cDNA
Authors: Conliffe Phyllis R. , Simmen Rosalia C. M. , Buhi William C. , Shiverick Kathleen T. 
Published: February 2005

AbstractProlactin‐like protein C (PLP‐C) is a major rat placental protein which is expressed during the second half of pregnancy and belongs to the growth hormone‐prolactin family. Here we report on the isolation of overlapping rat placental cDNAs which specify a transcript of 915 base pairs and predict a 205‐amino acid translated product. The full‐length cDNA shares 93% homology with the nucleotide sequence reported for PLP‐C, and the putative protein, which we designate PCRP (prolactin‐like protein C‐related protein), exhibits 88% homology with the PLP‐C precursor protein. PCRP lacks the signal sequence and the first 2 N‐terminal cysteine residues present in PLP‐C. Northern blot analysis indicated the basal zone‐specific expression of PCRP mRNA, with no detectable expression in decidua and labyrinth. Southern blot analysis of rat genomic DNA using PCRP cDNA as a probe demonstrated multiple hybridization bands, suggestive of a family of genes encoding prolactin‐like proteins. Western immunoblot analysis of basal zone culture media using a PCRP antipeptide antiserum revealed at least 5 immunoreactive proteins. The existence of a PLP‐C family of proteins in rat placenta after midpregnancy suggests their functional significance in the maintenance of pregnancy and fetal development. © 1995 Wiley‐Liss, Inc.
Comparative immunoreactivity of mouse and hamster sperm proteins recognized by an anti‐P26h hamster sperm protein
Authors: Bégin Sylvie , Bérubé Bruno , Boué Franck , Sullivan Robert 
Published: February 2005

AbstractThe binding of the spermatozoon to the zona pellucida is a species‐specific phenomenon. We have previously shown that the binding of hamster sperm to the homologous zona pellucida involves a sperm 26‐kDa glycoprotein, the P26h, originating in the epididymis. In order to establish to what extent this sperm protein is involved in the species‐specific recognition of the egg's extracellular coat, we have compared the inhibitory properties of anti‐P26h antibodies in a sperm‐zona pellucida assay using hamster and mouse gametes. Anti‐P26h IgGs inhibit, in a dose‐dependent manner, gamete interactions in both species, although in a less efficient manner in the mouse than in the hamster. While anti‐26kDa Fab fragments are as efficient as the intact IgG to inhibit hamster sperm‐zona pellucida binding, they have no effect on mouse gamete interaction. ELISA, Western blot, and immunohistochemical experiments have been performed in order to characterize the mouse antigen(s) recognized by the anti‐P26h antiserum. ELISA and Western blots showed that this antiserum recognized two proteins on mouse spermatozoa that are less reactive than the hamster P26h. These antigens are localized in the acrosomal region of epididymal spermatozoa of both species. These results indicate that the hamster P26H involved in zona pellucida interaction has certain unique epitopes, while others are common to the sperm of both species. © 1995 Wiley‐Liss, Inc.
Release of mouse eggs from metaphase arrest by protein synthesis inhibition in the absence of a calcium signal or microtubule assembly
Authors: Moses Ruth M. , Kline Douglas 
Published: February 2005

AbstractMouse egg activation, which includes release from meiotic metaphase II arrest, results from fertilization‐induced increase in intracellular calcium concentration ([Ca2+]i). However, during egg activation caused by exposure to the protein synthesis inhibitor, cycloheximide, [Ca2+]i did not change. Although eggs fertilized in the presence of microtubule inhibitors remain arrested at metaphase, eggs treated for 32 hr with cycloheximide and the microtubule inhibitor, colcemid, formed nuclei. In untreated eggs aged in culture for 24 hr, the microtubule spindles became deformed. These eggs formed nuclei after exposure to cycloheximide, but not the calcium ionophore A23187. Our results indicate that eggs in which protein synthesis is inhibited are released from metaphase without an increase in [Ca2+]i, and despite disruption of the Spindle. © 1995 Wiley‐Liss, Inc.