Journal
PLANT JOURNAL
Volume 58, Issue 4, Pages 606-617Publisher
WILEY
DOI: 10.1111/j.1365-313X.2009.03801.x
Keywords
rice (Oryza sativa L; ); glutelins; seed storage proteins; vacuolar processing enzyme; OsVPE1; cysteine protease
Categories
Funding
- National High Technology Research and Development Program of China [2006AA10A102, 2006AA100101, 2006AA10Z1A5, 2006BAD01A01-5]
- 111 project [B08025]
- China Postdoctoral Project [20070421025]
- Jiangsu Province Postdoctoral Project [0702030B]
Ask authors/readers for more resources
Rice (Oryza sativa L.) accumulates prolamines and glutelins as its major storage proteins. Glutelins are synthesized on rough endoplasmic reticulum as 57-kDa precursors; they are then sorted into protein storage vacuoles where they are processed into acidic and basic subunits. We report a novel rice glutelin mutant, W379, which accumulates higher levels of the 57-kDa glutelin precursor. Genetic analysis revealed that the W379 phenotype is controlled by a single recessive nuclear gene. Using a map-based cloning strategy, we identified this gene, OsVPE1, which is a homolog of the Arabidopsis beta VPE gene. OsVPE1 encodes a 497-amino-acid polypeptide. Nucleotide sequence analysis revealed a missense mutation in W379 that changes Cys269 to Gly. Like the wild-type protein, the mutant protein is sorted into vacuoles; however, the enzymatic activity of the mutant OsVPE1 is almost completely eliminated. Further, we show that OsVPE1 is incorrectly cleaved, resulting in a mature protein that is smaller than the wild-type mature protein. Taken together, these results demonstrate that OsVPE1 is a cysteine protease that plays a crucial role in the maturation of rice glutelins. Further, OsVPE1 Cys269 is a key residue for maintaining the Asn-specific cleavage activity of OsVPE1.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available