Yeast meiosis

Diploid cells of Saccharomyces sporulate when starved of nitrogen and fermentable carbon source. These nutritional signals converge on to the upstream regulatory region of IME1 gene. Ime1p interacts with Ume6p, a general repressor of sporulation-specific genes during mitotic growth and the complex activates the transcription of IME2 and other early meiotic genes unleashing a cascade of gene regulatory events that lead to initiation of pre-meiotic DNA replication, meiotic recombination, meiotic divisions and subsequently spore maturation.

A gene list comprising of approximately 1800 genes identified by microarray expression profiling studies to be involved in early sporulation and additional genes shown to have a sporulation phenotype upon deletion was used to derive a putative network underlying the poorly understood developmental pathway of sporulation. The resulting network with 1461 genes and 5247 interactions can be further filtered using querying utilities to selectively view the DNA-protein interactions or protein-protein interactions, various known functional modules operating during sporulation such as DNA replication/recombination/repair, Peptidolysis and proteolysis, Cell cycle regulation, regulation of transcription from Pol II promoter, ribosome complexes, etc.

GO Biological Process annotations show that several of tanscription factors are involved in regulation of glucose repression, starvation response to various nutrients, physiological stress response and cellular processes such as autophagy. This information can further be used to create hypothesis-based wet-lab experiments involving deletion of the specific binding site for each of these transcriptional regulators and monitoring the effect on IME1 transcription in response to the corresponding environmental condition.