Isolation and mapping of a human lung-specific gene, TSA1902, encoding a novel chitinase family member

• Published in: Gene Vol. 239; no. 2; pp. 325 - 331
• Main Authors: Saito, Akihiko, Ozaki, Kouichi, Fujiwara, Tsutomu, Nakamura, Yusuke, Tanigami, Akira
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier B.V 01.11.1999
• Subjects: Amino Acid Sequence; Base Sequence; Blotting, Northern; Chitinase; Chitinases - genetics; chitotriosidase; chromosome 1; Chromosome Mapping; Chromosomes, Human, Pair 1 - genetics; Cloning, Molecular; Differential display; DNA, Complementary - chemistry; DNA, Complementary - genetics; DNA, Complementary - isolation & purification; Female; Gene Expression; Humans; Isoenzymes - genetics; Lung - enzymology; Lung-specific gene; Male; Molecular Sequence Data; RNA, Messenger - genetics; RNA, Messenger - metabolism; Sequence Alignment; Sequence Analysis, DNA; Sequence Homology, Amino Acid; Tissue Distribution; TSA1902 gene; Chitinase; cR, centi-Ray; LOH, loss of heterozygosity; ORF, open reading frame; bp, base pair(s); Lung-specific gene; RH mapping, radiation hybrid mapping; cDNA, DNA complementary to RNA; RT–PCR, reverse transcription–PCR; PCR, polymerase chain reaction; RACE, rapid amplification of cDNA ends; TSA1902, gene encoding human lung-specific chitinase; Differential display
• ISSN: 0378-1119; 1879-0038
• DOI: 10.1016/S0378-1119(99)00394-7

Using differential display technique, we have isolated a novel human gene expressed specifically in the lung. Two forms of the gene, designated TSA1902, were transcribed by alternate mRNA splicing. The transcribed mRNAs, termed TSA1902-L and TSA1902-S, putatively encode proteins of 368 and 315 amino acids, respectively, which show high similarity to human chitotriosidase protein. The N-terminal region of TSA1902-L protein contains the conserved active site residues (DXXDXDXE) of the catalytic center of various chitinases which are essential for chitinase activity. The deduced protein sequence of TSA1902-S, however, does not possess this active site, with the N-terminal 54 amino acids present in TSA1902-L protein having been deleted. Both proteins lacked the secretory sequence of N-termini and, judging from the hydropathy profile, may be soluble proteins in the cytoplasm. Chromosomal mapping by radiation hybrid analysis localized this gene to the chromosome 1p13.1–p21.3.