Paper ID: 323
1 Charles University, Faculty of Science, BIOCEV (Czech Republic)
2 Institute of Microbiology of the CAS, v.v.i., BIOCEV (Czech Republic)
As with multicellular organisms, yeast and other single-celled microbes are able to differentiate when growing within organized multicellular communities such as colonies and biofilms. According to their 3-D architecture and presence of specific features, two major types of Saccharomyces cerevisiae colonies can be distinguished: structured biofilm colonies, formed by wild strains and smooth colonies, formed by laboratory strains that are adapted to plentiful conditions(J Cell Biol, 194: 679, 2011; Mol Cell 46:436, 2012; Cell Cycle 14: 3488, 2015). Differentiated cells, forming yeast colonies initiate various processes of metabolic reprogramming, gain specific properties, fulfill specific tasks and are able to mutually interact. Signaling molecules, low Mw metabolites and waste products released by cell subpopulations that are specifically localized within the structure further contribute to colony diversification and to differences in longevity of cells undergoing chronological ageing. Unusual combinations of activities of nutrient-sensing signaling pathways and other processes participating in cell reprogramming are involved in development of features, characteristic of different types of stationary-phase colony cells. Recently, we provided evidence that mitochondria play important roles in these processes (Oncotarget 7: 15299, 2016). Mitochondria of differentiated cell-types within smooth colonies differ significantly in numerous parameters and activate three distinct pathways of retrograde signaling that contribute to specific metabolic reprogramming of particular cells via regulation of expression of different metabolic proteins and transporters. These pathways differ in both upstream and downstream participating proteins. Mitochondrial functions seem to be different in smooth and biofilm colonies. This work was supported by GACR 15-08225S and 13-08605S and COST LD15129.