Open AccessStructure and expression of cytosolic cyclophilin/peptidyl-prolyl cis-trans isomerase of higher plants and production of active tomato cyclophilin in Escherichia coli.
Author(s) -
Charles S. Gasser,
Dorian Gunning,
Kim A. Budelier,
Sherri M. Brown
Publication year - 1990
Publication title -
proceedings of the national academy of sciences of the united states of america
Language(s) - English
Resource type - Journals
eISSN - 1091-6490
pISSN - 0027-8424
DOI - 10.1073/pnas.87.24.9519
Subject(s) - cyclophilin , biology , complementary dna , biochemistry , cis trans isomerases , gene , escherichia coli , microbiology and biotechnology , peptidylprolyl isomerase , prolyl isomerase , isomerase , southern blot , pin1
cDNA clones encoding proteins of approximately 18 kDa in which 83% of the amino acids are conserved relative to the published sequences of mammalian cyclophilin/rotamase (CyP) have been isolated from tomato, maize, and Brassica napus. In correspondence with the mammalian genes, but in contrast with the Neurospora gene and one yeast CyP gene, the plant CyP genes encode only mature proteins lacking transit peptides. RNA blot analyses demonstrate that CyP genes are expressed in all plant organs tested. Southern blots of genomic DNA indicate that there are small families (two to eight members) of CyP-related genes in maize and B. napus. A vector was constructed for expression of the tomato cDNA in E. coli. SDS/polyacrylamide gels show that extracts of appropriately induced cells harboring this vector contain nearly 40% of the protein as a single approximately 18-kDa band. While the majority of this protein is sequestered in insoluble inclusion bodies, the soluble extracts have higher levels of peptidyl-prolyl cis-trans isomerase (rotamase) activity than extracts of wild-type cells. This additional activity is sensitive to inhibition by the cyclic undecapeptide cyclosporin A.