objective: to investigate the association of c631t single nucleotide polymorphisms in spo11 gene with male infertilityfollowed by an in silico approach. spo11 is a gene involved in meiosis and spermatogenesis process, which in humans, this gene is located on chromosome 20 (20q13.2-13.3) with 13 exons. materials and methods: in a case-control study, 200 blood samples were collected from the ivf ...

Spo11 is a meiotic protein of fundamental importance as it is a conserved meiosis-specific transesterase required for meiotic recombination initiation in fungi, animals, and plants. Spo11 is homologous to the archaebacterial topoisomerase VIA (Top6A) gene, and its homologs are broadly distributed among eukaryotes, with some eukaryotes having more than one homolog. However, the evolutionary rela...

The Spo11 protein of yeast has been found to be covalently bound to double-strand breaks in meiosis, demonstrating a unique role of the protein in the formation of these breaks. Homologues of the SPO11 gene have been found in various eukaryotes, indicating that the machinery involved in meiotic recombination is conserved in eukaryotes. Here we report on SPO11 homologues in plants. In contrast t...

OBJECTIVE To investigate the association of C631T single nucleotide polymorphisms in SPO11 gene with male infertilityfollowed by an in silico approach. SPO11 is a gene involved in meiosis and spermatogenesis process, which in humans, this gene is located on chromosome 20 (20q13.2-13.3) with 13 exons. MATERIALS AND METHODS In a case-control study, 200 blood samples were collected from the IVF ...

Toward the global understanding of plant meiosis, it seems to be essential to decipher why all as yet sequenced plants need or at least encode for two different meiotic SPO11 genes. This is in contrast to mammals and fungi, where only one SPO11 is present. Both SPO11 in Arabidopsis thaliana are essential for the initiation of double strand breaks (DSBs) during the meiotic prophase. In nearly al...

We have shown earlier that DNA polymerase beta (Pol beta) localizes to the synaptonemal complex (SC) during Prophase I of meiosis in mice. Pol beta localizes to synapsed axes during zygonema and pachynema, and it associates with the ends of bivalents during late pachynema and diplonema. To test whether these localization patterns reflect a function for Pol beta in recombination and/or synapsis,...

Proper chromosome segregation and formation of viable gametes depend on synapsis and recombination between homologous chromosomes during meiosis. Previous reports have shown that the synaptic structures, the synaptonemal complexes (SCs), do not occur in yeast cells with the SPO11 gene removed. The Spo11 enzyme makes double-strand breaks (DSBs) in the DNA and thereby initiates recombination. The...

Mutations in the REM1 gene of Saccharomyces cerevisiae confer a semidominant hyper-recombination and hypermutable phenotype upon mitotic cells ( GOLIN and ESPOSITO 1977). These effects have not been observed in meiosis. We have examined the interactions of rem1 mutations with rad6-1, rad50 -1, rad52-1 or spo11 -1 mutations in order to understand the basis of the rem1 hyper-rec phenotype. The ra...

Spo11 is the topoisomerase-like enzyme responsible for the induction of the meiosis-specific double strand breaks (DSBs), which initiates the recombination events responsible for proper chromosome segregation. Nineteen PCR-induced alleles of SPO11 were identified and characterized genetically and cytologically. Recombination, spore viability and synaptonemal complex (SC) formation were decrease...

Aphids exhibit a form of phenotypic plasticity, called polyphenism, in which genetically identical females reproduce sexually during one part of the life cycle and asexually (via parthenogenesis) during the remainder of the life cycle. The molecular basis for aphid parthenogenesis is unknown. Cytological observations of aphid parthenogenesis suggest that asexual oogenesis evolved either through...