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Identification and characterization of a new isoform of small GTPase RhoE.

ABSTRACT: The Rho family of GTPases consists of 20 members including RhoE. Here, we discover the existence of a short isoform of RhoE designated as RhoE?, the first Rho GTPase isoform generated from alternative translation. Translation of this new isoform is initiated from an alternative start site downstream of and in-frame with the coding region of the canonical RhoE. RhoE? exhibits a similar subcellular distribution while its protein stability is higher than RhoE. RhoE? contains binding capability to RhoE effectors ROCK1, p190RhoGAP and Syx. The distinct transcriptomes of cells with the expression of RhoE and RhoE?, respectively, are demonstrated. The data propose distinctive and overlapping biological functions of RhoE? compared to RhoE. In conclusion, this study reveals a new Rho GTPase isoform generated from alternative translation. The discovery provides a new scope of understanding the versatile functions of small GTPases and underlines the complexity and diverse roles of small GTPases.

SUBMITTER: Dai Y

PROVIDER: S-EPMC7562701 | biostudies-literature | 2020 Oct

REPOSITORIES: biostudies-literature

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Identification and characterization of a new isoform of small GTPase RhoE.

Dai Yuan Y Luo Weijia W Yue Xiaojing X Ma Wencai W Wang Jing J Chang Jiang J

Communications biology 20201015 1

The Rho family of GTPases consists of 20 members including RhoE. Here, we discover the existence of a short isoform of RhoE designated as RhoEα, the first Rho GTPase isoform generated from alternative translation. Translation of this new isoform is initiated from an alternative start site downstream of and in-frame with the coding region of the canonical RhoE. RhoEα exhibits a similar subcellular distribution while its protein stability is higher than RhoE. RhoEα contains binding capability to R ...[more]

PMID: 33060740

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