Molecular and cell biology of porcine HSP47 during wound healing: complete cDNA sequence and regulation of gene expression.
Heat shock protein (HSP) 47 is a major stress-inducible protein that is localized to the endoplasmic reticulum of avian and mammalian cells and is thought to act as a molecular chaperone specific for the processing of procollagen. However, limited information is available regarding the regulation of HSP47 during wound healing. Using a polymerase chain reaction strategy, screening of a cDNA library, and RACE-polymerase chain reaction approaches, the sequence of a full-length porcine HSP47 cDNA has been identified. The cDNA contained 2096 bp that encodes for an 18 amino acid signal peptide and a mature protein coding region consisting of 401 amino acid residues. It also included 108 bp of the 5' noncoding region and a 731-bp 3' noncoding region. The deduced amino acid is 83% identical to chicken, 87% identical to mouse, 88% identical to rat, and 91% identical to human HSP47. It also shares between 26% and 30% identity with different members of the serine protease inhibitor superfamily. The protein contains a RDEL endoplasmic reticulum retention signal, and two potential glycosylation sites. All of these features are characteristic of HSP47 in higher vertebrates. Heat shock treatment of porcine fibroblasts led to up-regulation of HSP47 at both the transcriptional and translational levels. HSP47 protein levels were also up-regulated during skin wound healing in a pig model. Moreover, a higher molecular weight complex at approximately 140 Kda containing HSP47 was detected at the stage of healing that was coincident with the maximal transcriptional expression of HSP47 during wound healing in this animal model. Further investigation of how HSP47 is regulated during normal and abnormal skin wound healing may lead to new therapeutic approaches to improve the healing process.
McCaig Center for Joint Injury and Arthritis Research, University of Calgary, Calgary, Alberta, Canada.
Jian Fei
JF
Wang
Merle E
ME
Olson
Robert J
RJ
Winkfein
William M
WM
Kulyk
J Barry
JB
Wright
David A
DA
Hart
D000818:Animals; D018076:DNA, Complementary / Q000235:genetics*; D004195:Disease Models, Animal; D004721:Endoplasmic Reticulum / Q000235:genetics; D005260:Female; D005786:Gene Expression Regulation / Q000235:genetics*; D006360:Heat-Shock Proteins / Q000235:genetics*; D016133:Polymerase Chain Reaction; D017422:Sequence Analysis, DNA; D013552:Swine; D014945:Wound Healing / Q000235:genetics*; D014950:Wounds, Penetrating / Q000235:genetics*
D018076:DNA, Complementary; D006360:Heat-Shock Proteins