<i>Carex brevispicula</i> (Cyperaceae) is endemic to Korea and characterized by constricted achenes, short lateral spikes, awned staminate pistillate scales. The species classified in sect. <i>Mitratae</i> occurs throughout South Korea, perennating on mountains and/or rocky slopes under half shadow conditions. Meiotic chromosomes of the were examined this study, which 33...

Ski8p is implicated in degradation of non-poly(A) and double-stranded RNA, and in meiotic DNA recombination. We have identified the Sordaria macrospora SKI8 gene. Ski8p is cytoplasmically localized in all vegetative and sexual cycle cells, and is nuclear localized, specifically in early-mid-meiotic prophase, in temporal correlation with Spo11p, the meiotic double-strand break (DSB) transesteras...

Although in Saccharomyces cerevisiae the initiation of meiotic recombination, as indicated by double-strand break formation, appears to be functionally linked to the initiation of synapsis, meiotic chromosome synapsis in Drosophila females occurs in the absence of meiotic exchange. Electron microscopy of oocytes from females homozygous for either of two meiotic mutants (mei-W68 and mei-P22), wh...

During first meiotic prophase, homologous chromosomes are normally kept together by both crossovers and synaptonemal complexes (SC). In most eukaryotes, the SC disassembles at diplotene, leaving chromosomes joined by chiasmata. The correct co-orientation of bivalents at metaphase I and the reductional segregation at anaphase I are facilitated by chiasmata and sister-chromatid cohesion. In the a...

Two T7OH/+ translocation-carrying male mice were used in an investigation into the relation between the segregation pattern of the translocation caused multivalent at anaphase I and the position of the only chiasma in a long interstitial segment. Moreover, the relation between meiotic stage (from early diakinesis to metaphase I) and chiasma movement was assessed. It appeared that pronounced mov...

The cytologically diploid-like meiotic behavior of hexaploid wheat (i.e., exclusive bivalent pairing of homologues) is largely controlled by the pairing homoeologous gene Ph1. This gene suppresses pairing between homoeologous (partially homologous) chromosomes of the three closely related genomes that compose the hexaploid wheat complement. It has been previously proposed that Ph1 regulates mei...

The genus Heteropterys is one of the major genera in Malpighiaceae. However, few cytological and palynological studies were reported. The present work described for the first time the chromosome number, heterochromatin pattern, meiotic behavior, pollen viability and palynological aspects of Heteropterys ubellata, a very spread species. One large Brazilian population was evaluated using conventi...

Pitangueira (E. uniflora) is considered a diploid species with n = 11 and 2n 22 chromosomes, in genotypes the presence of seeds fruits. With pitangueira production apyrenic fruits existence, such behavior may be related to ploidy level. The objective this study was determine level accessions producing fruit without seed, as well observe meiotic possible chromosomal abnormalities. To check pitan...

The analysis of meiotic behavior has been widely used in the study of plants as they provide relevant information about the viability of a species. Meiosis boasts a host of highly conserved events and changes in genes that control these events will give rise to irregularities that can alter the normal course of meiosis and may lead to complete sterility of the plant. The recombination of genes ...

A-T (ataxia telangiectasia) individuals frequently display gonadal atrophy, and Atm-/- mice show spermatogenic failure due to arrest at prophase of meiosis I. Chromosomal movements take place during meiotic prophase, with telomeres congregating on the nuclear envelope to transiently form a cluster during the leptotene/zygotene transition (bouquet arrangement). Since the ATM protein has been imp...