Cooperation of two mRNA-binding proteins drives metabolic adaptation to iron deficiency

Expression of the yeast Cth2 protein stimulates degradation of mRNAs encoding proteins with Fe-dependent functions in metabolism, in iron storage and in other cellular processes. We demonstrate that in response to Fe deprivation, the Cth2-homologue, Cth1, stimulates specific degradation of mRNAs involved in mitochondrially localized activities that include respiration and amino acid biosynthesis. Furthermore, yeast cells grown under Fe deprivation accumulate mRNAs encoding proteins that function in glucose metabolism. These studies demonstrate a reprogramming of cellular metabolism during Fe-starvation dependent on the coordinated activities of two mRNA binding proteins. Keywords: Messenger RNAs down regulated by Cth1 and Cth2 proteins in response to Fe-limitation cth1cth2 cells independently transformed with pRS416 (V), pRS416-CTH1 (C) or pRS416-CTH2 (T) were grown in triplicate in SC-Ura containing 100 μM BPS until exponential growth phase (approximately 6hrs) at 30 degrees, RNA was extracted using a standard glass beads protocol, labeled and hybridized to Yeast Genome S98 Afffymetrix arrays.