Heat shock protein 47

Structure

HSP47 contains 3 beta sheets and 9 alpha helices. After binding with collagen no conformation change is observed.

Function

This protein is a member of the serpin superfamily of serine proteinase inhibitors. Its expression is induced by heat shock. HSP47 is expressed in the endoplasmic reticulum. These cells synthesize and secrete type I and type II collagen. The protein localizes to the endoplasmic reticulum lumen and binds collagen; thus it is thought to be a molecular chaperone involved in the maturation of collagen molecules. HSP47 is essential for the correct folding of procollagen. Antibodies directed to this protein have been found in patients with rheumatoid arthritis.

Interactions

Heat shock protein 47 has been shown to interact with collagens I, II, III, IV and V. It is involved in the secretion of collagen as well as the processing, assembly, and folding of collagen proteins. Hsp 47 binds specifically to procollagen and collagen only. The protein recognizes the triple helix of procollagen, two HSP47 proteins will bind to the leading and trailing strands of procollagen.

Clinical significance

Fibrosis

Fibrosis is the scarring of connective tissue, one attribute is the excess deposition of collagen in the extracellular matrix of tissue. Research has shown that HSPs have a role in fibrotic diseases. HSP47 has been shown to be pro-fibrosis in various fibrotic diseases. During the process of fibrosis, HSP47 is expressed and is involved in the production of collagen. HSP47 could be a potential therapeutic agent for fibrotic disease, a down-regulation of HSP47 leads to decreased fibrotic progression.

Deep vein thrombosis

HSP47 has a potential role in deep vein thrombosis.

References

References

1. "Entrez Gene: SERPINH1 serpin peptidase inhibitor, clade H (heat shock protein 47), member 1, (collagen binding protein 1)".
2. (December 2001). "The molecular interactions of heat shock protein 47 (Hsp47) and their implications for collagen biosynthesis". The Journal of Biological Chemistry.
3. (2013-01-09). "Molecular basis for the action of the collagen-specific chaperone Hsp47 SERPINH1 and its structure-specific client recognition.". Proceedings of the National Academy of Sciences of the United States of America.
4. (21 March 2000). "Heat Shock Protein 47: A Chaperone for the Fibrous Cap?". Circulation.
5. (November 2010). "Interactions of heat shock protein 47 with collagen and the stress response: an unconventional chaperone model?". Life Sciences.
6. (2020). "Heat Shock Proteins in Human Diseases". Springer International Publishing.
7. (2020-06-09). "Author Correction: TGF-β1-induced HSP47 regulates extracellular matrix accumulation via Smad2/3 signaling pathways in nasal fibroblasts". Scientific Reports.
8. (2023-08-25). "HSP47: A Therapeutic Target in Pulmonary Fibrosis". Biomedicines.
9. (April 13, 2023). "Sleep like a bear". [[Science (magazine).