Label-free comparative proteomics of Arabidopsis Clp protease mutants

摘要

Comparative in-depth proteome analysis of chloroplast protease mutants can be performed at the total leaf level with label-free quantification using the LTQ-Orbitrap. The most prominent changes in protein accumulation in the Clp mutants under study were found in the chloroplast proteome. Reduced accumulation of the Clp protease complex leads to an increase in accumulation of specific proteins involved in protein quality control (chaperones) and plastid gene expression, and a decrease in several lumenal and thylakoid-localized proteins. No ClpR4, ClpR2, ClpT1 and T2 were detected in the clpr4_1 null mutant suggesting a crucial role for ClpR4 in ClpR2, T1, and T2 accumulation.