Interaction between the tRNA-Binding and C-Terminal Domains of Yeast Gcn2 Regulates Kinase Activity In Vivo

dc.citation.doi10.1371/journal.pgen.1004991
dc.citation.issn1553-7390
dc.citation.issue2
dc.citation.jtitlePLoS Genetics
dc.citation.spage28
dc.citation.volume11
dc.contributor.authorLageix, S.
dc.contributor.authorZhang, J. W.
dc.contributor.authorRothenburg, Stefan
dc.contributor.authorHinnebusch, A. G.
dc.contributor.authoreidsr1hsv
dc.date.accessioned2016-04-04T22:13:52Z
dc.date.available2016-04-04T22:13:52Z
dc.date.published2015
dc.descriptionCitation: Lageix, S., Zhang, J. W., Rothenburg, S., & Hinnebusch, A. G. (2015). Interaction between the tRNA-Binding and C-Terminal Domains of Yeast Gcn2 Regulates Kinase Activity In Vivo. Plos Genetics, 11(2), 28. doi:10.1371/journal.pgen.1004991
dc.descriptionThe stress-activated protein kinase Gcn2 regulates protein synthesis by phosphorylation of translation initiation factor eIF2 alpha. Gcn2 is activated in amino acid-deprived cells by binding of uncharged tRNA to the regulatory domain related to histidyl-tRNA synthetase, but the molecular mechanism of activation is unclear. We used a genetic approach to identify a key regulatory surface in Gcn2 that is proximal to the predicted active site of the HisRS domain and likely remodeled by tRNA binding. Mutations leading to amino acid substitutions on this surface were identified that activate Gcn2 at low levels of tRNA binding (Gcd(-) phenotype), while other substitutions block kinase activation (Gcn(-) phenotype), in some cases without altering tRNA binding by Gcn2 in vitro. Remarkably, the Gcn(-) substitutions increase affinity of the HisRS domain for the C-terminal domain (CTD), previously implicated as a kinase autoinhibitory segment, in a manner dampened by HisRS domain Gcd(-) substitutions and by amino acid starvation in vivo. Moreover, tRNA specifically antagonizes HisRS/CTD association in vitro. These findings support a model wherein HisRS-CTD interaction facilitates the autoinhibitory function of the CTD in nonstarvation conditions, with tRNA binding eliciting kinase activation by weakening HisRS-CTD association with attendant disruption of the autoinhibitory KD-CTD interaction.
dc.identifier.urihttp://hdl.handle.net/2097/32246
dc.relation.urihttps://doi.org/10.1371/journal.pgen.1004991
dc.rightsCC0 1.0 Universal (CC0 1.0)
dc.rights.urihttps://creativecommons.org/publicdomain/zero/1.0/
dc.subjectUncharged Transfer-Rna
dc.subjectAcid-Starved Cells
dc.subjectProtein-Kinase
dc.subjectAmino-Acid
dc.subjectTranslation Initiation
dc.subjectSaccharomyces-Cerevisiae
dc.titleInteraction between the tRNA-Binding and C-Terminal Domains of Yeast Gcn2 Regulates Kinase Activity In Vivo
dc.typeArticle

Files

Original bundle

Now showing 1 - 1 of 1
Loading...
Thumbnail Image
Name:
journal.pgen.1004991.pdf
Size:
2.03 MB
Format:
Adobe Portable Document Format