NMR analysis of the backbone dynamics of the small GTPase Rheb and its interaction with the regulatory protein FKBP38.
NMR analysis of the backbone dynamics of the small GTPase Rheb and its interaction with the regulatory protein FKBP38.
FEBS Lett. 2017 Nov 30;:
Authors: De Cicco M, Kiss L, Dames SA
Abstract
Ras homologue enriched in brain (Rheb) is a small GTPase that regulates mammalian/mechanistic target of rapamycin complex 1 (mTORC1) and, thereby, cell growth and metabolism. Cycling between the inactive GDP- and the active GTP-bound state modulates the backbone dynamics of a C-terminal truncated form, Rheb?CT, which is suggested to influence its interactions. Here, we investigated the interactions between Rheb?CT and the proposed Rheb-binding domain of the regulatory protein FKBP38. The weak interactions with the GTP-analogue- (GppNHp-) but not the GDP-bound state observed here, appear to accelerate the GDP to GTP exchange, but only very weakly compared to a genuine GEF. Thus, FKBP38 is most likely not a GEF, but a Rheb effector that may function in membrane targeting of Rheb. This article is protected by copyright. All rights reserved.
PMID: 29194576 [PubMed - as supplied by publisher]
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