Numerous reports were devoted to the variation of sperm length in relation to sperm competition amongst species. However, studies on intraspecific variations of sperm size are very scarce and the number of sperm measured, very limited. This paper investigates within-individual, between-individual and between-population variation of sperm length in the two cosmopolitan species, D. simulans and D. melanogaster. Sperm length distributions are completely discriminated against with these two species, with the mean values equal to 1.121 +/- 0.002 and 1.989 +/- 0.008 mm, respectively. Results of intraspecific variation show a contrasting pattern between the two species. The mode of sperm length distributions is much less variable in D. simulans than in D. melanogaster. The sperm size divergence is unaffected whenever the two species are in sympatry (tested at 'Evolution Canyon', Mount Carmel, Israel) or in allopatry, but the two species react differentially to abiotic local factors. D. melanogaster, in contrast to D. simulans, shows a clinal pattern in sperm size associated with drought. We discussed this pattern in relation to the potential role of sperm length in the ongoing process of non-random mating and incipient sympatric speciation observed in this locality in D. melanogaster.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1023/b:gene.0000017644.63389.57 | DOI Listing |
Non-crossover gene conversion is a type of meiotic recombination characterized by the non-reciprocal transfer of genetic material between homologous chromosomes. Gene conversions are thought to occur within relatively short tracts of DNA, estimated to be in the order of 100-1,000 bp in humans. However, the number of observable gene conversion tracts per study has so far been limited by the use of pedigree or sperm-typing data to detect gene conversion events.
View Article and Find Full Text PDFJ Am Chem Soc
January 2025
Department of Chemistry, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, Massachusetts 02139, United States.
The remarkable efficiency with which enzymes catalyze small-molecule reactions has driven their widespread application in organic chemistry. Here, we employ automated fast-flow solid-phase synthesis to access catalytically active full-length enzymes without restrictions on the number and structure of noncanonical amino acids incorporated. We demonstrate the total syntheses of iron-dependent myoglobin (BsMb) and sperm whale myoglobin (SwMb).
View Article and Find Full Text PDFJ Hum Reprod Sci
December 2024
Department of Anatomy, Lab for Molecular Reproduction and Genetics, All India Institute of Medical Sciences, New Delhi, India.
Infertility presents multifaceted challenges that encompass both physical and emotional burdens. Yoga, as a comprehensive system of mind-body medicine, serves as an effective intervention for managing male factor infertility, a complex lifestyle disorder with significant psychosomatic elements. This review explores the transformative role of yoga in addressing both the emotional and physical dimensions of infertility.
View Article and Find Full Text PDFbioRxiv
January 2025
ISEM, Université de Montpellier, CNRS, IRD, EPHE, Montpellier, France.
are endosymbiotic bacteria inducing various reproductive manipulations of which cytoplasmic incompatibility (CI) is the most common. CI leads to reduced embryo viability in crosses between males carrying and uninfected females or those carrying an incompatible symbiont strain. In the mosquito , the Pip causes highly complex crossing patterns.
View Article and Find Full Text PDFJ Hazard Mater
January 2025
Department of Occupational and Environmental Health, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, PR China; Key Laboratory of Environment and Health, Ministry of Education & Ministry of Environmental Protection, and State Key Laboratory of Environmental Health (incubating), School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, PR China. Electronic address:
Bisphenol A (BPA), a common endocrine disrupting chemical (EDC), has shown detrimental effects on sperm quality and function in experimental models. However, epidemiological evidence is inconsistent and also there exists a notable lack of data on its analogues, such as bisphenol F (BPF) and bisphenol S (BPS). To investigate the relationships between BPA, BPF and BPS exposures and sperm DNA damage, we conducted a cross-sectional study recruiting 474 Chinese men from an infertility clinic in Wuhan, China.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!