Normally, meiotic crossovers in conjunction with sister-chromatid cohesion establish a physical connection between homologs that is required for their accurate segregation during the first meiotic division. However, in some organisms an alternative mechanism ensures the proper segregation of bivalents that fail to recombine. In Drosophila oocytes, accurate segregation of ...

of Achiasmate Homologs in Drosophila Male Meiosis Sharon E. Thomas,1 Morvarid Soltani-Bejnood,2 Peggy Roth,3 meiotic proteins specifically required for this process. Stromalin in Meiosis (SNM) is a diver- gent member of the SCC3/SA/STAG family of cohesin proteins, and Modifier of Mdg4 in Meiosis (MNM) is one

The reduction of chromosome number during meiosis is achieved by two successive rounds of chromosome segregation, called meiosis I and meiosis II. While meiosis II is similar to mitosis in that sister kinetochores are bi-oriented and segregate to opposite poles, recombined homologous chromosomes segregate during the first meiotic division. Formation of chiasmata, ...

The chiasma is a structure that forms between a pair of homologous chromosomes by crossover recombination and physically links the homologous chromosomes during meiosis. Chiasmata are essential for the attachment of the homologous chromosomes to opposite spindle poles (bipolar attachment) and their subsequent segregation to the ...

Drosophila melanogaster oocytes heterozygous for mutations in the ?-tubulin 67C gene (?tub67C) display defects in centromere positioning during prometaphase of meiosis I. The centromeres do not migrate to the poleward edges of the chromatin mass, and the chromatin fails to stretch during spindle lengthening. These results suggest that the poleward forces acting at the kinetochore are compromised ...

Phytoplasmas cause several important diseases in California¿s almond and fruit tree orchards. A phytoplasma associated with almond brown line (ABL) disease, peach yellow leafroll phytoplasma (PYLR-P) and pear decline phytoplasma (PD-P) are genetically related based on homology in the 16S-23S rDNA sp...

Even though CR has shown to enhance base excision repair (BER) and nucleotide excision repair (NER) capacities, it has not been reported whether CR can enhance non-homologous end joining (NHEJ) activity. To examine the effect of CR on NHEJ activity, ad libitum (AL)- and calorie restricted (CR)-dieted rats were used. Age-dependent decline of NHEJ activity ...

Homologous (granulosa cell-granulosa cell) gap junction (GJ) contacts increase in ovarian follicles of Atlantic croaker (Micropogonias undulatus) during the early (first) stage of maturation, but their profile during the second stage [i.e., during maturation-inducing hormone (MIH)-mediated meiotic resumption] is unknown. The profile of homologous GJ ...