Collagen beta(1-o)galactosyltransferase 1

Collagen beta(1-o)galactosyltransferase 1 (also known as GLT25D1) is an enzyme that in humans is encoded by the GLT25D1 gene. This enzyme is part of the glycosyltransferase family, specifically the galactosyltransferase subfamily.

Function

The GLT25D1 enzyme is responsible for the glycosylation of hydroxylysine residues in collagen. This process is crucial for the stability of the collagen triple helix structure. The enzyme catalyzes the transfer of a galactose molecule to the hydroxylysine residues, forming a beta-galactosidic bond. This reaction is a key step in the biosynthesis of collagen.

Clinical significance

Mutations in the GLT25D1 gene have been associated with various connective tissue disorders, including Ehlers-Danlos syndrome. These disorders are characterized by abnormalities in the structure or synthesis of collagen, leading to symptoms such as skin hyperextensibility, joint hypermobility, and tissue fragility.

Structure

The GLT25D1 enzyme is a type II membrane protein, meaning it is anchored in the cell membrane with its catalytic domain facing the endoplasmic reticulum lumen. The enzyme consists of a short N-terminal cytoplasmic tail, a single transmembrane domain, and a large C-terminal catalytic domain.

See also

• Collagen
• Glycosylation
• Galactosyltransferase
• Ehlers-Danlos syndrome