cerevisiae, the structural axis is formed by cohesin (Rec8), Red1 and Hop1 proteins. cerevisiae, Sycp1 in mammals) proteins, forming the so-called synaptonemal complex. Axes of homologous chromosomes are themselves bound to each other by transversal filaments made of (Zip1 in S. The DNA lying outside protein binding sites forms loops along the axis. The formation of this structure is due to bonding of cohesin and several other proteins on specific DNA sites, and to their assembly in a protein complex forming an axis. Ī specific chromosomal structure is formed during meiosis, and plays a key role in recombination events. It is also known that DSB frequency is strongly correlated with GC-content, open chromatin structure - and histone methylation. cerevisiae genome revealing that DSBs are more abundant before gene starts. This property has been used to make a high-resolution DSB density map of the S. Two Spo11 proteins work in concert to cut both DNA strands and, after the cleavage, each Spo11 is bound to a DNA fragment. ![]() The Spo11 protein, a transesterase highly conserved through evolution and required for meiotic recombination in Saccharomyces cerevisiae, Caenorhabditis elegans, Drosophila and mammals, causes DSBs. This allows evolution to explore different allelic combinations through recombinations that are more likely to occur in some regions than others, and that are initiated by DNA double-strand breaks (DSBs). A critical step is homologous recombination between homologous chromosomes, in which both crossover and non-crossover events occur, resulting in a different gene content of the offspring chromosomes. In sexually reproducing eukaryotes, the production of gametes relies on meiosis, during which a diploid cell is divided into four haploid cells. SPoRE outbreaks previous DSB predictors, which are based on nucleotide patterning, and it reaches 85% of success rate in DSB prediction compared to 54% obtained by available tools on a benchmarked dataset. When compared to Saccharomyces cerevisiae experimental data, SPoRE predicts axis protein and DSB positions with high sensitivity and precision, axis protein density with an average local correlation r=0.63 and DSB density with an average local correlation r=0.62. SPoRE can be used for prediction and it is parameterised in an obvious way that makes it easy to understand from a biological viewpoint. It models DSB accumulation at approximated gene promoter positions with intergenic region length and GC-content. It models axis proteins accumulation at gene 5’-ends with a discrete approximation of their diffusion and convection along genes. ![]() It is based on a combination of genomic signals, based on what is known from wet-lab experiments, whose contribution is precisely quantified. SPoRE is a mathematical model that describes the non-uniform localisation of DSB and axis proteins sites, and distinguishes high versus low protein density. ![]() ![]() So far, recombination regions have been mainly determined by experiments, both expensive and time-consuming. It is initiated via programmed DNA double-strand breaks (DSB) and involves a specific axial chromosomal structure. Meiotic recombination between homologous chromosomes provides natural combinations of genetic variations and is a main driving force of evolution.
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