Lysine ubiquitination and acetylation of human cardiac 20S proteasomes.

ABSTRACT:

Purpose

Altered proteasome functions are associated with multiple cardiomyopathies. While the proteasome targets polyubiquitinated proteins for destruction, it itself is modifiable by ubiquitination. We aim to identify the exact ubiquitination sites on cardiac proteasomes and examine whether they are also subject to acetylations.

Experimental design

Assembled cardiac 20S proteasome complexes were purified from five human hearts with ischemic cardiomyopathy, then analyzed by high-resolution MS to identify ubiquitination and acetylation sites. We developed a library search strategy that may be used to complement database search in identifying PTM in different samples.

Results

We identified 63 ubiquitinated lysines from intact human cardiac 20S proteasomes. In parallel,

SUBMITTER: Zong N 

PROVIDER: S-EPMC5094860 | biostudies-literature | 2014 Aug

REPOSITORIES: biostudies-literature