Asparagine Linked Glycosylation Protein 14 (ALG14)

Asparagine (N)-glycosylation is an essential modification that regulates protein folding and stability. ALG13 and ALG14 constitute the UDP-GlcNAc transferase, which catalyzes a key step in endoplasmic reticulum N-linked glycosylation. The deduced 216-amino acid protein has a calculated molecular mass of 24.1 kD and shares 35% amino acid identity with yeast Alg14. Alg14 spans the membrane but lack any sequences predicted to play a direct role in sugar catalysis. Fluorescence microscopy and subcellular fractionation studies localized S. cerevisiae Alg14 protein to the endoplasmic reticulum membrane.Human ALG13 and ALG14 each functionally complemented the corresponding Alg13 and Alg14 mutants in S. cerevisiae strains and partially restored the defective glycosylation phenotype.