bluuebunny/crossref_metadata_2025_split huggingface dataset:
apd1
+, a Gene Required for Red Pigment Formation in ade6 Mutants of Schizosaccharomyces pombe, Encodes an Enzyme Required for Glutathione Biosynthesis: A Role for Glutathione and a Glutathione-Conjugate Pump
Authors: Chaudhuri Biswendu , Ingavale Susham , Bachhawat Anand K 
Published: January 2021

Mutants in the adenine biosynthetic pathway of yeasts (ade1 and ade2 of Saccharomyces cerevisiae, ade6 and ade7 of Schizosaccharomyces pombe) accumulate an intense red pigment in their vacuoles when grown under adenine-limiting conditions. The precise events that determine the formation of the pigment are however, still unknown. We have begun a genetic investigation into the nature and cause of pigmentation of ade6 mutants of S. pombe and have discovered that one of these pigmentation defective mutants, apd1 (adenine pigmentation defective), is a strict glutathione auxotroph. The gene apd1 + was found to encode the first enzyme in glutathione biosynthesis, γ-glutamylcysteine synthetase, gcs1 +. This gene when expressed in the mutant could confer both glutathione prototrophy and the characteristic red pigmentation, and disruption of the gene led to a loss in both phenotypes. Supplementation of glutathione in the medium, however, could only restore growth but not the pigmentation because the cells were unable to achieve sufficient intracellular levels of glutathione. Disruption of the second enzyme in glutathione biosynthesis, glutathione synthetase, gsh2 +, also led to glutathione auxotrophy, but only a partial defect in pigment formation. A reevaluation of the major amino acids previously reported to be present in the pigment indicated that the pigment is probably a glutathione conjugate. The ability of vanadate to inhibit pigment formation indicated that the conjugate was transported into the vacuole through a glutathione-conjugate pump. This was further confirmed using strains of S. cerevisiae bearing disruptions in the recently identified glutathione-conjugate pump, YCF1, where a significant reduction in pigment formation was observed. The pump of S. pombe is distinct from the previously identified vacuolar pump, hmt1p, for transporting cadystin peptides into vacuoles of S. pombe.
stand still, a Drosophila Gene Involved in the Female Germline for Proper Survival, Sex Determination and Differentiation
Authors: Pennetta Giuseppa , Pauli Daniel 
Published: January 2021

We identified a new gene, stand still (stil), required in the female germline for proper survival, sex determination and differentiation. Three strong loss-of-function alleles were isolated. The strongest phenotype exhibited by ovaries dissected from adult females is the complete absence of germ cells. In other ovaries, the few surviving germ cells frequently show a morphology typical of primary spermatocytes. stil is not required either for fly viability or for male germline development. The gene was cloned and found to encode a novel protein. stil is strongly expressed in the female germ cells. Using P[stil +] transgenes, we show that stil and a closely localized gene are involved in the modification of the ovarian phenotypes of the dominant alleles of ovo caused by heterozygosity of region 49 A-D. The similarity of the mutant phenotypes of stil to that of otu and ovo suggests that the three genes function in a common or in parallel pathways necessary in the female germline for its survival, sex determination and differentiation.
Molecular and Genetic Analysis of REC103, an Early Meiotic Recombination Gene in Yeast
Authors: Gardiner Jack M , Bullard Steven A , Chrome Chris , Malone Robert E 
Published: January 2021

In the yeast Saccharomyces cerevisiae at least 10 genes are required to begin meiotic recombination. A new early recombination gene REC103 is described in this paper. It was initially defined by the rec103-1 mutation found in a selection for mutations overcoming the spore inviability of a rad52 spo13 haploid strain. Mutations in REC103 also rescue rad52 in spo13 diploids. rec103 spo13 strains produce viable spores; these spores show no evidence of meiotic recombination. rec103 SPO13 diploids produce no viable spores, consistent with the loss of recombination. Mutations in REC103 do not affect mitotic recombination, growth, or repair. These phenotypes are identical to those conferred by mutations in several other early meiotic recombination genes (e.g., REC102, REC104, REC114, MEI4, MER-2, and SPO11). REC103 maps to chromosome VII between ADE5 and RAD54. Cloning and sequencing of REC103 reveals that REC103 is identical to SK18, a gene that depresses the expression of yeast double-stranded (“killer”) (ds)RNA viruses. REC103/SK18 is transcribed in mitotic cells and is induced ∼15-fold in meiosis. REC103 has 26% amino acid identity to the Schizosaccharomyces pombe rec14 + gene; mutations in both genes confer similar meiotic phenotypes, suggesting that they may play similar roles in meiotic recombination.
Occurrence of Repeat Induced Point Mutation in Long Segmental Duplications of Neurospora
Authors: Perkins David D , Margolin Brian S , Selker Eric U , Haedo S D 
Published: January 2021

Abstract
Previous studies of repeat induced point mutation (RIP) have typically involved gene-size duplications resulting from insertion of transforming DNA at ectopic chromosomal positions. To ascertain whether genes in larger duplications are subject to RIP, progeny were examined from crosses heterozygous for long segmental duplications obtained using insertional or quasiterminal translocations. Of 17 distinct mutations from crossing 11 different duplications, 13 mapped within the segment that was duplicated in the parent, one was closely linked, and three were unlinked. Half of the mutations in duplicated segments were at previously unknown loci. The mutations were recessive and were expressed both in haploid and in duplication progeny from Duplication × Normal, suggesting that both copies of the wild-type gene had undergone RIP. Seven transition mutations characteristic of RIP were found in 395 base pairs (bp) examined in one ro-11 allele from these crosses and three were found in ~750 bp of another. A single chain-terminating C to T mutation was found in 800 bp of arg-6. RIP is thus responsible. These results are consistent with the idea that the impaired fertility that is characteristic of segmental duplications is due to inactivation by RIP of genes needed for progression through the sexual cycle.
Mutational Analysis of Cdc19p, a Schizosaccharomyces pombe MCM Protein
Authors: Forsburg Susan L , Sherman Daniel A , Ottilie Sabine , Yasuda J Randy , Hodson Jeffrey A 
Published: January 2021

The cdc19 + gene encodes an essential member of the MCM family of replication proteins in Schizosaccharomyces pombe. We have examined the structure and function of the Cdc19p protein using molecular and genetic approaches. We find that overproduction of wild-type Cdc19p in wild-type cells has no effect, but cdc19-P1 mutant cells do not tolerate elevated levels of other MCM proteins or overexpression of mutant forms of Cdc19p. We have found genetic interactions between cdc19 + and genes encoding subunits of DNA polymerase δ and the replication initiator cdc18 +. We have constructed a series of point mutations and sequence deletions throughout Cdc19p, which allow us to distinguish essential from nonessential regions of the protein. Not surprisingly, conserved residues in the MCM homology domain are required for protein function, but some residues outside the core homology domain are dispensable.
Extended Reproductive Roles of the fruitless Gene in Drosophila melanogaster Revealed by Behavioral Analysis of New fru Mutants
Authors: Villella Adriana , Gailey Donald A , Berwald Barbra , Ohshima Saiyou , Barnes Phillip T , Hall Jeffrey C 
Published: January 2021

The fruitless mutants fru3 and fru4 were assessed for sex-specific reproductive-behavioral phenotypes and compared to the previously reported fru mutants. Among the several behavioral anomalies exhibited by males expressing these relatively new mutations, some are unique. fru3 and fru4 males are less stimulated to court females than and fru1 and fru2. No courtship pulse song is generated by either fru3 or fru4 males, even though they perform brief wing extensions. fru3 and fru4 males display significantly less chaining behavior than do fru1 males. The hierarchy of courtship responses by fru males directed toward females vs. males, when presented with both sexes simultaneously, is that fru1 males perform vigorous and indiscriminant courtship directed at either sex; fru4 males are similarly indiscriminant, but courtship levels were lower than fru1; fru2 males prefer females; fru3 males show a courtship bias toward males. fru3 and fru4 males essentially lack the Muscle of Lawrence (MOL). On several reproductive criteria, there was no difference between fru-variant females and fru +. The increases in phenotypic severity measured for the new mutants are discussed in the context of the emerging molecular genetics of fru and with regard to the gene's position within the sex-determination pathway.
Size and Sequence Polymorphism in the Isocitrate Dehydrogenase Kinase/Phosphatase Gene (aceK) and Flanking Regions in Salmonella enterica and Escherichia coli
Authors: Nelson Kimberlyn , Wang Fu-Sheng , Boyd E Fidelma , Selander Robert K 
Published: January 2021

Abstract
The sequence of aceK, which codes for the regulatory catalytic enzyme isocitrate dehydrogenase kinase/phosphatase (IDH K/P), and sequences of the 5′ flanking region and part or all of the 3′ flanking region were determined for 32 strains of Salmonella enterica and Escherichia coli. In E. coli, the aceK gene was 1734 bp long in 13 strains, but in three strains it was 12 bp shorter and the stop codon was TAA rather than TGA. Strains with the shorter aceK lacked an open reading frame (f728) downstream between aceK and iclR that was present, in variable length, in the other strains. Among the 72 ECOR strains, the truncated aceK gene was present in all isolates of the B2 group and half of those of the D group. Other variant conditions included the presence of IS1 elements in two strains and large deletions in two strains. The aceK-aceA intergenic region varied in length from 48 to 280 bp in E. coli, depending largely on the number of repetitive extragenic palindromic (REP) sequences present. Among the ECOR strains, the number of REP elements showed a high degree of phylogenetic association, and sequencing of the region in the ECOR strains permitted partial reconstruction of its evolutionary history. In S. enterica, the normal length of aceK was 1752 bp, but three other length variants, ranging from 1746 to 1785 bp, were represented in five of the 16 strains examined. The flanking intergenic regions showed relatively minor variation in length and sequence. The occurrence of several nonrandom patterns of distribution of polymorphic synonymous nucleotide sites indicated that intragenic recombination of horizontally exchanged DNA has contributed to the generation of allelic diversity at the aceK locus in both species.
Identification and Characterization of Genes That Interact With lin-12 in Caenorhabditis elegans
Authors: Tax Frans E , Thomas James H , Ferguson Edwin L , Horvitzt H Robert 
Published: January 2021

Abstract
We identified and characterized 14 extragenic mutations that suppressed the dominant egg-laying defect of certain lin-12 gain-of-function mutations. These suppressors defined seven genes: sup-l7, lag-2, sel-4, sel-5, sel-6, sel-7 and sel-8. Mutations in six of the genes are recessive suppressors, whereas the two mutations that define the seventh gene, lag-2, are semi-dominant suppressors. These suppressor mutations were able to suppress other lin-12 gain-of-function mutations. The suppressor mutations arose at a very low frequency per gene, 10-50 times below the typical loss-of-function mutation frequency. The suppressor mutations in sup1 7 and lag-2 were shown to be rare non-null alleles, and we present evidence that null mutations in these two genes cause lethality. Temperature-shift studies for two suppressor genes, sup1 7and lag-2, suggest that both genes act at approximately the same time as lin-12in specifying a cell fate. Suppressor alleles of six of these genes enhanced a temperature-sensitive loss-of-function allele of glp-1, a gene related to lin-12 in structure and function. Our analysis of these suppressors suggests that the majority of these genes are part of a shared lin-12/glp-1 signal transduction pathway, or act to regulate the expression or stability of lin-12 and glp-1.
P-Element Insertion Alleles of Essential Genes on the Third Chromosome of Drosophila melanogaster: Mutations Affecting Embryonic PNS Development
Authors: Salzberg Adi , Prokopenko Sergei N , He Yuchun , Tsai Peter , Pál Margit , Maróy Péter , Glover David M , Deák Péter , Bellen Hugo J 
Published: January 2021

Abstract
To identify novel genes and to isolate tagged mutations in known genes that are required for the development of the peripheral nervous system (PNS), we have screened a novel collection of 2460 strains carrying lethal or semilethal P-element insertions on the third chromosome. Monoclonal antibody 22C10 was used as a marker to visualize the embryonic PNS. We identified 109 mutant strains that exhibited reproducible phenotypes in the PNS. Cytological and genetic analyses of these strains indicated that 87 mutations affect previously identified genes: tramtrack (n = 18 alleles), string (n = 15), cyclin A (n = 13), single-minded (n = 13), Delta (n = 9), neuralized (n = 4), pointed (n = 4), extra macrochaetae (n = 4), pospero (n = 3), tartan (n = 2), and pebble (n = 2). In addition, 13 mutations affect genes that we identified recently in a chemical mutagenesis screen designed to isolate similar mutants: hearty (n = 3), dursotonals (n = 2), pauarotti (n = 2), sanpodo (n = 2), dalmatian (n = 1), missensed (n = 1), senseless (n = 1), and sticky chl (n = 1). The remaining nine mutations define seven novel complementation groups. The data presented here demonstrate that this collection of Pelements will be useful for the identification and cloning of novel genes on the third chromosome, since &gt;70% of mutations identified in the screen are caused by the insertion of a Pelement. A comparison between this screen and a chemical mutagenesis screen undertaken earlier highlights the complementarity of the two types of genetic screens.
Bayesian Procedures for Discriminating Among Hypotheses With Discrete Distributions: Inheritance in the Tetraploid Astilbe biternata
Authors: Olson Matthew S 
Published: January 2021

Abstract
Discrimination between disomic and tetrasomic inheritance aids in determining whether tetraploids originated by allotetraploidy or autotetraploidy, respectively. Past assessments of inheritance in tetraploids have used analyses whereby each inheritance hypothesis is tested independently. I present a Bayesian analysis that is appropriate for discriminating among several inheritance hypotheses and can be used in any case where hypotheses are defined by discrete distributions. The Bayesian approach incorporates prior knowledge of the probability of occurrence of disomic and tetrasomic hypotheses so that the results of the analysis are not biased by the fact that there is a single tetrasomic hypothesis and multiple disomic hypotheses. This analysis is used to interpret data from crosses in the tetraploid Astilbe biternata, a herbaceous plant native to the southern Appalachians. The progeny ratios from all crosses favored the hypothesis of disomic inheritance at both the PGM and slow-PGI loci. These results support earlier cytogenetic evidence for the allotetraploid origin of Astilbe biternata.
Assisted Reproductive Techniques and Genetic Manipulation in the Common Marmoset
Authors: Park Jung Eun , Sasaki Erika 
Published: January 2021

AbstractGenetic modification of nonhuman primate (NHP) zygotes is a useful method for the development of NHP models of human diseases. This review summarizes the recent advances in the development of assisted reproductive and genetic manipulation techniques in NHP, providing the basis for the generation of genetically modified NHP disease models. In this study, we review assisted reproductive techniques, including ovarian stimulation, in vitro maturation of oocytes, in vitro fertilization, embryo culture, embryo transfer, and intracytoplasmic sperm injection protocols in marmosets. Furthermore, we review genetic manipulation techniques, including transgenic strategies, target gene knock-out and knock-in using gene editing protocols, and newly developed gene-editing approaches that may potentially impact the production of genetically manipulated NHP models. We further discuss the progress of assisted reproductive and genetic manipulation techniques in NHP; future prospects on genetically modified NHP models for biomedical research are also highlighted.
Machine Advice with a Warning about Machine Limitations: Experimentally Testing the Solution Mandated by the Wisconsin Supreme Court
Authors: Engel Christoph , Grgić-Hlača Nina 
Published: January 2021

Abstract
The Wisconsin Supreme Court allows machine advice in the courtroom only if accompanied by a series of warnings. We test 878 US lay participants with jury experience on fifty past cases where we know ground truth. The warnings affect their estimates of the likelihood of recidivism and their confidence, but not their decision whether to grant bail. Participants do not get better at identifying defendants who recidivated during the next two years. Results are essentially the same if participants are warned in easily accessible language, and if they are additionally informed about the low accuracy of machine predictions. The decision to grant bail is also unaffected by the warnings mandated by the Supreme Court if participants do not first decide without knowing the machine prediction. Oversampling cases where defendants committed violent crime does not change results either, whether coupled with machine predictions for general or for violent crime. Giving participants feedback and incentivizing them for finding ground truth has a small, weakly significant effect. The effect becomes significant at conventional levels when additionally using strong graphical warnings. Then participants are less likely to follow the advice. But the effect is counterproductive: they follow the advice less if it actually is closer to ground truth.
One Size Does Not Fit All: Relationships between Size of Family Forest Holdings and Owner Attitudes and Behaviors
Authors: Butler Brett J , Caputo Jesse , Robillard Amanda L , Sass Emma M , Sutherland Chris 
Published: January 2021

AbstractAn estimated 10 million families, individuals, trusts, and estates own 39 percent of the forestland in the United States, excluding interior Alaska. Using segmented regression, the relationships between size of forest holdings and the attitudes and behaviors of these family forest ownerships were tested using data from the 2018 iteration of the USDA Forest Service’s National Woodland Owner Survey. All 16 variables tested have significant relationships with size of forest holdings, and 13 have one or more breakpoints, ranging from 40 to 5,854 ac, where the relationships between the variables change. Timber as a reason for owning, timber harvesting activities, management plan, advice received, land certified, tax program participation, cost share, recreation, land tenure, recreation, taxes and heirs as concerns, land transfer, and income from forestland have positive relationships with size of forest holdings; resident ownership has a negative relationship; and wildlife as a reason for owning and owner age have mixed relationships.
PIV test of the flow field of a centrifugal pump with four types of impeller blades
Authors: Shi Baocheng , Zhou Kaili , Pan Jianpeng , Zhang XingKai , Ying Ruomeng , Wu Lijuan , Zhang Yindi 
Published: January 2021

Abstract
Flow fields for various impellers were measured using water and a two-phase liquid–solid mixture with a particle image velocimetry system in a centrifugal rotating frame in controlled conditions. After measuring absolute velocity vectors in impeller passages, the vectors were decomposed based on the triangle speed principle and the distribution of relative velocity vectors within the impeller was obtained. Then, the distribution of particles and their influence on the performance of different impellers were analyzed. The following conclusions were made from the comparison of relative velocity vector field: first, the wear on the outlet of blades can be mitigated effectively by reducing the outlet angle of impeller blades; second, the pump with a double-arc-shaped profile had a more uniform and stable flow field distribution and higher performance than that with a single-arc profile; and finally, the “jet–wake” structure can be improved significantly by using impellers with long and short blades, resulting in a remarkable reduction in energy loss and improvement in pump efficiency. We also found that solid particles were mainly distributed at the outlet of the impeller and volute wall, while the concentration distribution of large particles tended to match the pressure surface. This research can provide some theoretical guidance for the design and optimization of two-phase flow centrifugal pumps.
Postural orthostatic tachycardia syndrome following open thoracoabdominal aortic aneurysm repair
Authors: Manuel Lucy , Fong Laura S , Mamo Andrew , Varcoe Ramon , Saw Wilfred , Grant Peter 
Published: January 2021

Abstract
Postural orthostatic tachycardia syndrome (POTS) is a variant of cardiovascular autonomic disorder characterised by an excessive heart rate on standing and orthostatic intolerance. We present a rare case of a 38-year-old man who underwent open repair of a thoracoabdominal aortic aneurysm for a chronic Stanford type B aortic dissection whose recovery was complicated by POTS. He received blood transfusions and was commenced on metoprolol, fludrocortisone and ivabradine with significant improvement in his symptoms. Correct assessment of postoperative tachycardia including postural telemetry is the key to identifying this condition and its successful management.