PtCP1 Is an Extraplastidial Cysteine Protease Involved in Leaf Protein Degradation of Populus tomentosa Carr
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Updated: May 28, 2026

Understanding the Development of Compensatory Pathways in a Mutant Malaria Parasite Harbouring Hypomorphic Allele of Plant-Like Kinases
Published on: November 22, 2024
Yawei Fan1, Jingyi Han1, Xiatong Liu1
1State Key Laboratory of Tree Genetics and Breeding, The Tree and Ornamental Plant Breeding and Biotechnology Laboratory of National Forestry and Grassland Administration, College of Biological Sciences and Biotechnology, Beijing Forestry University, Beijing 100083, China.
Abstract:
Protein turnover is essential for cellular metabolism, organelle biogenesis, stress adaptation, and ultimately the viability of cells and tissues. Papain-like cysteine proteases (PLCPs) are one of the vital components in protein degradation. PLCPs have been reported to act in senescence-associated proteolysis, but their roles in vegetative growth remain unclear. We identified PtCP1, an AALP-like PLCP in Populus tomentosa, localized to the vacuole and acid-triggered activated. CRISPR/Cas9-generated loss-of-function mutant (d7) showed dwarfism and non-stomatal photosynthetic limitations. On the other hand, the gain-of-function line (EM, deleted ERFNIN domain) exhibited accelerated growth and enhanced photosynthetic parameters. We showed d7 had the accumulation of Rubisco, which was the most important protein in photosynthetic carbon fixation. Transcriptomics revealed dysregulated carbon metabolism in d7. This data supported PtCP1-mediated proteolysis regulated photosynthetic carbon assimilation via altered Rubisco turnover, and then it increased the biomass accumulation during vegetative growth in woody plants.
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