Activity-Based Profiling of Papain-like Cysteine Proteases During Late-Stage Leaf Senescence in Barley.

ABSTRACT: Leaf senescence is a developmental process that allows nutrients to be remobilized and transported to sink organs. Previously, papain-like cysteine proteases (PLCPs) have been found to be highly expressed during leaf senescence in different plant species. In this study, we analyzed active PLCPs in barley (Hordeum vulgare L.) leaves during the terminal stage of natural senescence. Anion exchange chromatography of protein extracts from barley leaves, harvested six weeks after anthesis, followed by activity assays using the substrates Z-FR-AMC and Z-RR-AMC, revealed a single prominent peak corresponding to active PLCPs. This hydrolytic activity was completely inhibited by E-64, a potent and irreversible inhibitor of cysteine proteases. Fractions enriched for PLCP activity were affinity

SUBMITTER: Schepetkin IA 

PROVIDER: S-EPMC12567500 | biostudies-literature | 2025 Oct

REPOSITORIES: biostudies-literature