ROLE OF RAC3 COACTIVATOR IN CELLULAR DIFFERENTIATION

MARÍA FERNANDA RUBIO

Buenos Aires

Congreso; REUNIÓN CONJUNTA DE SOCIEDADES DE BIOCIENCIAS; 2017

SAIC

RAC3 is a member of the p160 familyof Steroid Receptor Coactivators and is highlyexpressed in several human cancers, contributingto cell proliferation and cellular transformation.In this work, we have studied the role of RAC3 duringadipogenesis. This is a highly regulated process whichinvolves the cell cycle arrest and changes in the geneexpression pattern, which is required for morphologicalremodeling. We found that RAC3 expression levels aredownregulated during specific stimulus induced-adipocytedifferentiation. Moreover, a constitutive decreaseof RAC3 expression through a shRNA potentiates adipocytedifferentiation shortening the time at which theadipocyte markers Perilipin, PPAR- and Oil Red O stainingare detected. The RAC3 down regulation favors cellarrest and autophagy. Early and late autophagy inhibitorsblock adipocyte differentiation of control cells, but inhibitthe shRAC3 differentiation partially. Although autophagyis required for adipogenesis, these results suggestthat additional signals could be triggered by RAC3 downregulation. We conclude that RAC3 is a key regulator ofadipogenesis whose down regulation generates cellulararrest and a permissive environment for autophagy allowingthe early adipocyte differentiation.