Spartin activates atrophin-1-interacting protein 4 (AIP4) E3 ubiquitin ligase and promotes ubiquitination of adipophilin on lipid droplets.

ABSTRACT:

Background

Spartin protein is involved in degradation of epidermal growth factor receptor and turnover of lipid droplets and a lack of expression of this protein is responsible for hereditary spastic paraplegia type 20 (SPG20). Spartin is a multifunctional protein that associates with many cellular organelles, including lipid droplets. Recent studies showed that spartin interacts with E3 ubiquitin ligases that belong to the neural precursor cell-expressed developmentally downregulated gene (Nedd4) family, including atrophin-1-interacting protein 4 (AIP4/ITCH). However, the biological importance of the spartin-AIP4 interaction remains unknown.

Results

In this study, we show that spartin is not a substrate for AIP4 activity and that spartin's binding to AIP4 significantly incr

SUBMITTER: Hooper C 

PROVIDER: S-EPMC2887783 | biostudies-literature | 2010 May

REPOSITORIES: biostudies-literature