Systematic Study Of ATG Genes In The Regulation Of Yeast Autophagy

Autophagy is a highly evolutionarily conserved process essential for sustaining cellular integrity, homeostasis and survival. There are three major forms of autophagy: macroautophagy, microautophagy and chaperone-mediated autophagy(CMA). We use the term autophagy to refer to macroautophagy hereafter.Aberrant autophagy is associated with diverse human pathologies. Therefore, the in-depth study of autophagy mechanism is very necessary. The ATG genes in mammalian have corresponding homologue in yeast, which indicates that autophagy process is conservative. At present, 40 AuTophaGy-related(ATG) genes have thus far been identified in yeast. There are significant and unique benefits to deal with the organism, including the capability to do in vivo genetic screening quickly and relatively easily, and the myriad unique assays are available to monitor different steps of autophagy in S. cerevisiae. Thus, in this study we select yeast as the experimental organism for the autophagy research.Based on S. cerevisiae this work analyzes and classifies 28 yeast mutants with knockout of ATG knockout genes by observing the GFP-ATG8 dynamic localization changes inside and outside the yeast vacuoles under nitrogen starvation. Meanwhile, together with bioinformatics analysis about the key ATG protein phosphorylation, this work also divides the ATG key genes into two categories: genes whose knockout doesn't affect autophagy and genes whose knockout leads to autopahgy defect under nitrogen starvation.After classifying the autophagy related genes classification under nitrogen starvation, this work integrates yeast protein phosphorylation site data and sorts out 125 phosphorylation site from18 ATG protein. Then, iGPS software is used to predict autophagy protein specific kinase and finally 53 protein kinase correspomding to 13 ATG protein identified. Using this data, the network of ATG proteins and specific kinases is constructed.In the future, the research work will design experiments to validate whether the phosphorylation of ATG proteins participates in autophagy induced by nitrogen starvation. At the same time, work will be conducted to study the functional relationship between ATG proteins and kinases. Hoping this work of autophagy would provide new methods and insights for future research in autophagy mechanism.