Project description:The centromere is essential for the inheritance of genetic information on eukaryotic chromosomes. Epigenetic regulation of centromere identity has been implicated in genome stability, karyotype evolution and speciation. However, little is known regarding the manner in which centromere dysfunction affects the chromosomal architectures. Here we show that in the fission yeast Schizosaccharomyces pombe, the conditional deletion of the centromere produces survivors that carry either neocentromere-acquired chromosome at the sub-telomeric region or acentric chromosome rescued by inter-telomere fusion with other chromosome. The ratio of neocentromere formation to telomere fusion is considerably decreased by inactivation of genes involved in RNA interference (RNAi)-dependent heterochromatin formation. By affecting the modes of chromosomal reorganization, the genomic distribution of heterochromatin may influence the fate of karyotype evolution. Keywords: ChIP-chip
Project description:We established a two-step approach to centromere-replacement (Figure 1A in outline, and Supplementary data in detail). FiC31 integrase was used to place a candidate sequence or an empty vector adjacent to the native centromere of chromosome 2 of CBS2777, and Bxb1 integrase was subsequently used to delete the native centromere.
Project description:Meiosis is a specialized cell division that generates gametes, such as eggs and sperm. Errors in meiosis result in miscarriages and are the leading cause of birth defects, however the molecular origins of these defects remain unknown. Studies in model organisms are beginning to identify the genes and pathways important for meiosis, but the parts list is still poorly defined. Here we present a comprehensive catalogue of genes required for meiosis in the fission yeast, Schizosaccharomyces pombe. Our genome-wide functional screen surveyed all non-essential genes for roles in chromosome segregation and spore formation. Novel genes required at distinct stages of the meiotic chromosome segregation and differentiation programme were identified. Preliminary characterization implicated three of these genes in centrosome/spindle pole body function, centromere and cohesion function. Our findings represent a near-complete parts list of genes required for meiosis in fission yeast, providing a valuable resource to advance our molecular understanding of meiosis.
