HGNC Approved Gene Symbol: MUC19
Cytogenetic location: 12q12 Genomic coordinates (GRCh38): 12:40,393,394-40,570,757 (from NCBI)
Mucus is a viscoelastic substance that covers the epithelial surface of various tissues, providing lubrication and protection from environmental insults. The gel-like properties of mucus are generally attributed to the physical properties and structural features of gel-forming mucins, such as MUC19 (Chen et al., 2004).
By searching databases for novel gel-forming mucins, followed by RT-PCR and 3-prime and 5-prime RACE of mouse and human salivary gland RNA, Chen et al. (2004) cloned 3-prime fragments of mouse and human MUC19. The full-length human protein predicted from the genomic sequence contains more than 7,000 amino acids and includes 3 N-terminal von Willebrand factor (VWF; 613160) D domains, followed by mucin-like thr/ser-rich repeats, a VWF C domain, and a C-terminal cystine-knot domain. Northern blot analysis detected MUC19 expression in human trachea and submandibular gland, but not in lung or parotid gland. RT-PCR confirmed expression in submandibular gland and trachea, but little to no expression was detected in other tissues. Mouse Muc19 was expressed predominantly in sublingual and submandibular gland, with lower expression in trachea. In situ hybridization detected MUC19 in mucous cells of mouse submandibular gland and in the submucosal gland of human trachea.
Chen et al. (2004) determined that the human MUC19 gene spans more than 180 kb.
By genomic sequence analysis, Chen et al. (2004) mapped the human MUC19 gene to chromosome 12q12 and the mouse Muc19 gene to chromosome 15E3.
Chen, Y., Zhao, Y. H., Kalaslavadi, T. B., Hamati, E., Nehrke, K., Le, A. D., Ann, D. K., Wu, R. Genome-wide search and identification of a novel gel-forming mucin MUC19/Muc19 in glandular tissues. Am. J. Resp. Cell Molec. Biol. 30: 155-165, 2004. [PubMed: 12882755] [Full Text: https://doi.org/10.1165/rcmb.2003-0103OC]