The Dictyostelium discoideum RACK1 orthologue has roles in growth and development

Cell Communication and Signaling

Research

Annette Müller-Taubenberger¹  Napoleon Nosa Omosigho²  Angelika A Noegel²  Karthic Swaminathan²  Tanja Y Riyahi²  Markus Plomann³ 

[1] Institute of Anatomy and Cell Biology, Ludwig-Maximilians-University, 80336, München, Germany;Institute of Biochemistry I, Medical Faculty, Center for Molecular Medicine Cologne (CMMC) and Cologne Excellence Cluster on Cellular Stress Responses in Aging-Associated Diseases (CECAD), University of Cologne, 50931, Köln, Germany;Institute of Biochemistry II, Medical Faculty, University of Cologne, 50931, Köln, Germany;

关键词: Dictyostelium discoideum;    G protein signaling;    RACK1;    WD40 repeat protein;    Phosphoinositides;    Phosphorylation;    Dimerization;   

DOI  :  10.1186/1478-811X-12-37

 received in 2014-02-21, accepted in 2014-06-06,  发布年份 2014

来源: Springer

【 摘 要 】

BackgroundThe receptor for activated C-kinase 1 (RACK1) is a conserved protein belonging to the WD40 repeat family of proteins. It folds into a beta propeller with seven blades which allow interactions with many proteins. Thus it can serve as a scaffolding protein and have roles in several cellular processes.ResultsWe identified the product of the Dictyostelium discoideum gpbB gene as the Dictyostelium RACK1 homolog. The protein is mainly cytosolic but can also associate with cellular membranes. DdRACK1 binds to phosphoinositides (PIPs) in protein-lipid overlay and liposome-binding assays. The basis of this activity resides in a basic region located in the extended loop between blades 6 and 7 as revealed by mutational analysis. Similar to RACK1 proteins from other organisms DdRACK1 interacts with G protein subunits alpha, beta and gamma as shown by yeast two-hybrid, pulldown, and immunoprecipitation assays. Unlike the Saccharomyces cerevisiae and Cryptococcus neoformans RACK1 proteins it does not appear to take over Gβ function in D. discoideum as developmental and other defects were not rescued in Gβ null mutants overexpressing GFP-DdRACK1. Overexpression of GFP-tagged DdRACK1 and a mutant version (DdRACK1mut) which carried a charge-reversal mutation in the basic region in wild type cells led to changes during growth and development.ConclusionDdRACK1 interacts with heterotrimeric G proteins and can through these interactions impact on processes specifically regulated by these proteins.

【 授权许可】

Unknown   
© Omosigho et al.; licensee BioMed Central Ltd. 2014. This article is published under license to BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly credited. The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated.