Expression of the collagen VI α5 and α6 chains in normal human skin and in skin of patients with collagen VI-related myopathies.
Collagen VI is an extracellular matrix protein with critical roles in maintaining muscle and skin integrity and function. Skin abnormalities, including predisposition to keratosis pilaris and abnormal scarring, were described in Ullrich congenital muscular dystrophy (UCMD) and Bethlem myopathy (BM) patients carrying mutations in COL6A1, COL6A2, and COL6A3 genes, whereas COL6A5, previously designated as COL29A1, was linked to atopic dermatitis. To gain insight into the function of the newly identified collagen VI α5 and α6 chains in human skin, we studied their expression and localization in normal subjects and in genetically characterized UCMD and BM patients. We found that localization of α5, and to a lesser extent α6, is restricted to the papillary dermis, where the protein mainly colocalizes with collagen fibrils. In addition, both chains were found around blood vessels. In UCMD patients with COL6A1 or COL6A2 mutations, immunolabeling for α5 and α6 was often altered, whereas in a UCMD and in a BM patient, each with a COL6A3 mutation, expression of α5 and α6 was apparently unaffected, suggesting that these chains may substitute for α3, forming α1α2α5 or α1α2α6 heterotrimers.
Sabatelli
Patrizia
P
Istituto Di Genetica Molecolare-CNR, Istituto Ortopedico Rizzoli, Bologna, Italy.
Gara
Sudheer K
SK
Grumati
Paolo
P
Urciuolo
Anna
A
Gualandi
Francesca
F
Curci
Rosa
R
Squarzoni
Stefano
S
Zamparelli
Alessandra
A
Martoni
Elena
E
Merlini
Luciano
L
Paulsson
Mats
M
Bonaldo
Paolo
P
Wagener
Raimund
R
D001706:Biopsy; D001808:Blood Vessels / Q000378:metabolism; D015153:Blotting, Western; D024142:Collagen Type VI / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D005455:Fluorescent Antibody Technique; D006801:Humans; D009136:Muscular Dystrophies / Q000235:genetics / Q000378:metabolism / Q000473:pathology; D010641:Phenotype; D017434:Protein Structure, Tertiary; D012598:Sclerosis / Q000235:genetics / Q000378:metabolism / Q000473:pathology; D012867:Skin / Q000378:metabolism* / Q000473:pathology
C524742:COL6A5 protein, human; C555240:COL6A6 protein, human; D024142:Collagen Type VI