Pairing and recombination of homologous chromosomes are essential for ensuring correct segregation of chromosomes in meiosis. In S. pombe, chromosomes are first bundled at the telomeres (forming a telomere bouquet) and then aligned by oscillatory movement of the elongated "horsetail" nucleus. Telomere clustering and subsequent chromosome alignment promote pairing of homologous chromosomes. However, this telomere-bundled alignment of chromosomes cannot be responsible for the specificity of chromosome pairing. Thus, there must be some mechanism to facilitate recognition of homologous partners after telomere clustering. Recent studies in S. pombe have shown that RNA transcripts retained on the chromosome, or RNA bodies, may play a role in recognition of homologous chromosomes for pairing. Acting as fiducial markers of homologous loci they would abrogate the need for direct DNA sequence homology searching.
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http://dx.doi.org/10.4161/nucl.22732 | DOI Listing |
Acta Neurobiol Exp (Wars)
January 2025
Laboratory of Animal Models, Nencki Institute of Experimental Biology, Polish Academy of Sciences, Warsaw, Poland.
The phosphatase and tensin homolog deleted on chromosome 10 (PTEN) gene is a critical tumor suppressor that plays an essential role in the development and functionality of the central nervous system. Located on chromosome 10 in humans and chromosome 19 in mice, PTEN encodes a protein that regulates cellular processes such as division, proliferation, growth, and survival by antagonizing the PI3K‑Akt‑mTOR signaling pathway. In neurons, PTEN dephosphorylates phosphatidylinositol‑3,4,5‑trisphosphate (PIP3) to PIP2, thereby modulating key signaling cascades involved in neurogenesis, neuronal migration, and synaptic plasticity.
View Article and Find Full Text PDFBrief Bioinform
November 2024
Department of Biology, École Normale Supérieure, 46 rue d'Ulm, 75005 Paris, France.
Acute Promyelocytic Leukaemia (APL) arises from an aberrant chromosomal translocation involving the Retinoic Acid Receptor Alpha (RARA) gene, predominantly with the Promyelocytic Leukaemia (PML) or Promyelocytic Leukaemia Zinc Finger (PLZF) genes. The resulting oncoproteins block the haematopoietic differentiation program promoting aberrant proliferative promyelocytes. Retinoic Acid (RA) therapy is successful in most of the PML::RARA patients, while PLZF::RARA patients frequently become resistant and relapse.
View Article and Find Full Text PDFPLoS Genet
January 2025
Department of Zoology, University of British Columbia, Vancouver, British Columbia, Canada.
The synaptonemal complex (SC) is a protein-rich structure essential for meiotic recombination and faithful chromosome segregation. Acting like a zipper to paired homologous chromosomes during early prophase I, the complex is a symmetrical structure where central elements are connected on two sides by the transverse filaments to the chromatin-anchoring lateral elements. Despite being found in most major eukaryotic taxa implying a deeply conserved evolutionary origin, several components of the complex exhibit unusually high rates of sequence turnover.
View Article and Find Full Text PDFHortic Res
January 2025
Key Laboratory of Xinjiang Phytomedicine Resource and Utilization of Ministry of Education, Key Laboratory of Oasis Town and Mountain-basin System Ecology of Xinjiang Production and Construction Corps, College of Life Sciences, Shihezi University, Shihezi 832003, China.
Alfalfa is one of the most economically valuable forage crops in the world. However, molecular cytogenetic studies in alfalfa lag far behind other cash crops and have reached a bottleneck. Here, we developed a novel chromosome identification system by designing 21 oligo probes in specific regions of each chromosome, which can be used as a barcode to simultaneously distinguish all chromosomes in a cell.
View Article and Find Full Text PDFNucleic Acids Res
January 2025
MOE Key Laboratory of Biosystems Homeostasis and Protection, College of Life Sciences, Zhejiang University, No.866 Yuhangtang Road, 310058, Hangzhou, China.
Meiosis in mammalian oocytes is interrupted by a prolonged arrest at the germinal vesicle stage, during which oocytes have to repair DNA lesions to ensure genome integrity or otherwise undergo apoptosis. The FIRRM/FLIP-FIGNL1 complex dissociates RAD51 from the joint DNA molecules in both homologous recombination (HR) and DNA replication. However, as a type of non-meiotic, non-replicative cells, whether this RAD51-dismantling mechanism regulates genome integrity in oocytes remains elusive.
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