RRC ID 54948
Author Nakase Y, Matsumoto T.
Title The RHEB-mTOR axis regulates expression of Tf2 transposons in fission yeast.
Journal J Cell Sci
Abstract The human TSC2 gene, mutations in which predispose individuals to the disease tuberous sclerosis complex (TSC), encodes a GTPase-activating protein for the GTPase RHEB. Loss of TSC2 results in constitutive activation of RHEB and its target mammalian target of rapamycin (mTOR). We have previously reported that fission yeast (Schizosaccharomyces pombe) Tf2 retrotransposons (hereafter Tf2s) are abnormally induced upon nitrogen starvation in cells lacking the tsc2+ gene (Δtsc2), a homolog of the human TSC2 gene, and in cells with a dominant-active mutation in the fission yeast RHEB GTPase (rhb1-DA4). We report here that induction of Tf2s in these mutants is suppressed upon overexpression of the cgs2+ gene, which encodes a cAMP-specific phosphodiesterase, or upon deletion of components in the glucose/cAMP signaling pathway, namely Cyr1, Pka1, Tor1 and the stress-activated transcription factor Atf1. The results suggest that the glucose/cAMP signaling pathway is downregulated when cells are starved for nitrogen. We also show that Tf2 proteins are degraded via autophagy, which is under control of Tor2, a homolog of human mTOR. It appears that failure in the two processes, downregulation of the glucose/cAMP signaling pathway and induction of autophagy, allows abnormal induction of Tf2s upon nitrogen starvation in Δtsc2 and rhb1-DA4 cells.
Volume 131(22)
Published 2018-11-21
DOI 10.1242/jcs.221457
PII jcs.221457
PMID 30301783
MeSH Animals Humans Monomeric GTP-Binding Proteins / genetics Monomeric GTP-Binding Proteins / metabolism* Nitrogen / deficiency Nitrogen / metabolism Schizosaccharomyces / genetics Schizosaccharomyces / metabolism Schizosaccharomyces pombe Proteins / biosynthesis* Schizosaccharomyces pombe Proteins / genetics Schizosaccharomyces pombe Proteins / metabolism* Signal Transduction TOR Serine-Threonine Kinases / genetics TOR Serine-Threonine Kinases / metabolism*
IF 4.517
Times Cited 0
Yeast FY7285 pTN-L1(pAL-KS)?