Collagen VI acts as a cell-binding protein. Trimers composed of three different chains: alpha-1(VI), alpha-2(VI), and alpha-3(VI) or alpha-5(VI) or alpha-6(VI). Deposed in the extracellular matrix of skeletal muscle. Expressed in skin, followed by lung, small intestine, colon and testis. In skin, it is expressed in the epidermis with strongest staining in suprabasal viable layers. In ATOD patients, it is absent in the most differentiated upper spinous and granular layers (at protein level). Prolines at the third position of the tripeptide repeating unit (G-X-Y) are hydroxylated in some or all of the chains. Patients affected by atopic dermatitis display an abnormal distribution of COL29A1 mRNA and protein in skin suggesting that COL29A1 may be involved in the pathogenesis of the disease. Belongs to the type VI collagen family. Truncated N-terminus.