Msn2p and Msn4p Control a Large Number of Genes Induced at the Diauxic Transition Which Are Repressed by Cyclic AMP in Saccharomyces cerevisiae

Abstract

The multicopy suppressors of the snf1 defect, Msn2p and Msn4p transcription factors (Msn2/4p), activate genes through the stress-responsive cis element (CCCCT) in response to various stresses. This cis element is also the target for repression by the cyclic AMP (cAMP)-signaling pathway. We analyzed the two-dimensional gel electrophoresis pattern of protein synthesis of themsn2 msn4 double mutant and compared it with that of the wild-type strain during exponential growth phase and at the diauxic transition. Thirty-nine gene products (including those ofALD3, GDH3, GLK1, GPP2,HSP104, HXK1, PGM2,SOD2, SSA3, SSA4, TKL2,TPS1, and YBR149W) are dependent upon Msn2/4p for their induction at the diauxic transition. The expression of all these genes is repressed by cAMP. Thirty other genes identified during this study are still inducible in the mutant. A subset of these genes were found to be superinduced at the diauxic transition, and others were subject to cAMP repression (including ACH1,ADH2, ALD6, ATP2, GPD1,ICL1, and KGD2). We conclude from this analysis that Msn2/4p control a large number of genes induced at the diauxic transition but that other, as-yet-uncharacterized regulators, also contribute to this response. In addition, we show here that cAMP repression applies to both Msn2/4p-dependent and -independent control of gene expression at the diauxic shift. Furthermore, the fact that all the Msn2/4p gene targets are subject to cAMP repression suggests that these regulators could be targets for the cAMP-signaling pathway.

Chemosensitization of fungal pathogens to antimicrobial agents using benzo analogs

“…Because sensitivity of the gsh mutants resulted from glutathione auxotrophy, attention was focused on the Mn-SOD gene/mutant. The Mn-SOD gene is downstream in the yeast HOG1 (MAPK) oxidative stress signaling-pathway (Boy-Marcotte et al, 1998;Rep et al, 2000Rep et al, , 2001 and appeared to be a promising candidate as a target for fungal control.…”

Stress-controlled transcription factors, stress-induced genes and stress tolerance in budding yeast

“…As mentioned, with respect to the presence of STRE sequences in their promoter, many yeast genes are candidates for regulation through the general stress response pathway [13,14]. The list includes genes involved in carbon metabolism, transporters, proteases and genes with protective functions against di¡erent types of stress, including HSP104, CTT1 and the trehalose metabolism genes TPS1, TPS2, TPS3 and TSL1 [13,14,34]. In agreement with their role as main STRE transcription factors, msn2msn4 double mutants show a higher sensitivity to di¡erent stresses, including carbon source starvation, heat shock, osmotic and oxidative stresses [20,35].…”

Two-dimensional protein map of an ?ale?-brewing yeast strain: proteome dynamics during fermentation

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