Proteome analysis of Arabidopsis Lon1 protease mutant

Intracellular selective proteolysis is an important protein quality control process for maintenance of protein homeostasis by removing either the defective polypeptides or deleterious protein aggregates. The ATP-dependent Lon protease is a key component of protein quality control and highly conserved across the kingdoms of living organisms. In Arabidopsis thaliana Lon1 (At5g26860) is dual targeted to mitochondria and chloroplasts. Lon1 mutant plants (lon1-1) exhibit a post-embryonic growth retardation phenotype accompanied with aberrant mitochondria morphology and reduced respiratory capacity. To identify the effect of loss of Lon1 proteolytic activity on the protein level of the plant, the proteome profile of lon1-1 mutant was analyzed by mass spectrometry and compared to the proteome of the wild type plants (Col-0) used as a reference. Total protein extraction was performed under denature conditions of 8 days old seedling, grown vertically on petri dishes at 22 o C in the dark from independent biological replicates. The protein extract was subjected to Ultra High Pressure nanoLC-MS/MS.