RRC ID 4835
著者 Jin H, Hong Z, Su W, Li J.
タイトル A plant-specific calreticulin is a key retention factor for a defective brassinosteroid receptor in the endoplasmic reticulum.
ジャーナル Proc Natl Acad Sci U S A
Abstract Mammalian calreticulin (CRT) is a multifunctional Ca(2+)-binding protein involved in more than 40 cellular processes in various subcellular compartments, such as Ca(2+) storage and protein folding in the endoplasmic reticulum (ER). CRT homologues were discovered in plants almost 15 years ago, and recent studies revealed that many plant species contain 2 or more CRTs that are members of 2 distinct families, the CRT1/2 family and the plant-specific CRT3 family. However, little is known about their physiological functions. Here we report ebs2 (EMS-mutagenized bri1 suppressor 2) as an allele-specific suppressor of bri1-9, a dwarf Arabidopsis mutant caused by retention of a defective brassinosteroid receptor in the ER. EBS2 encodes the Arabidopsis CRT3 that interacts with ER-localized bri1-9 in a glycan-dependent manner. Loss-of-function ebs2 mutations compromise ER retention of bri1-9 and suppress its dwarfism, whereas EBS2 over-expression enhances its dwarf phenotype. In contrast, mutations of 2 other CRTs or their membrane-localized homologues calnexins had little effect on bri1-9. A domain-swapping experiment revealed that the positively charged C-terminal tail of CRT3 is crucial for its "bri1-9-retainer" function. Our study revealed not only a functional role for a plant-specific CRT, but also functional diversity among the 3 Arabidopsis CRT paralogues.
巻・号 106(32)
ページ 13612-7
公開日 2009-8-11
DOI 10.1073/pnas.0906144106
PII 0906144106
PMID 19597144
PMC PMC2726391
MeSH Alleles Amino Acid Sequence Arabidopsis / genetics Arabidopsis / metabolism* Arabidopsis Proteins / chemistry Arabidopsis Proteins / genetics Arabidopsis Proteins / metabolism* Brassinosteroids Calreticulin / chemistry Calreticulin / genetics Calreticulin / metabolism* Cholestanols / metabolism* Cloning, Molecular Endoplasmic Reticulum / metabolism* Gene Expression Regulation, Plant Genes, Plant Molecular Sequence Data Mutation / genetics Phenotype Plant Lectins / metabolism Protein Binding Receptors, Cell Surface / metabolism* Species Specificity Steroids, Heterocyclic / metabolism* Suppression, Genetic
IF 9.412
引用数 80
WOS 分野 BIOCHEMISTRY & MOLECULAR BIOLOGY
リソース情報
シロイヌナズナ / 植物培養細胞・遺伝子 pda04763 pda12372