Biol. Pharm. Bull., 26(3),361-364, March 2003

Notes

Trypsinogen hL Expressed in the Human Lung Is a New Member of the Trypsinogen Family

Yasuhiro IMAMURA,^a Masataka KATSU,^b Kaoru SAKAI,^b Yuushi OKUMURA,^d Hiroyoshi ARIGA,^*,c and Hiroshi KIDO^d

^a Division of Molecular Biology, Research Institute for Biological Sciences, Tokyo University of Science; 2669 Yamazaki, Noda, Chiba 278-0022, Japan: ^b Research Laboratories, Mitsubishi Pharma Co. Ltd.; 1000 Kamoshida-cho, Aoba-ku, Yokohama 227-0033 Japan: ^c Graduate School of Pharmaceutical Sciences, Hokkaido University; Kita 12, Nishi 6, Kitaku, Sapporo 060-0812, Japan: and ^d Division of Enzyme Chemistry, Institute for Enzyme Research, University of Tokushima; 3-18-17 Kuramoto-cho, Tokushima 770-8503, Japan. * To whom correspondence should be addressed. e-mail: hiro@pharm.hokudai.ac.jp

Molecular cloning of cDNA encoding a new member of the trypsinogen family, named trypsinogen hL, was carried out by PCR using human lung cDNAs as templates. The primary structure of trypsinogen hL was found to be a prepro-protein and a catalytic triad, 64His, 108Asp and 201Ser. It was also found that trypsinogen hL is specifically expressed in the human lung, the expression level being 30-times higher than those in other tissues tested. A phylogenic tree analysis showed that trypsinogen hL is a new member of the trypsinogen family, a family of serine protease family proteins.

Key words trypsinogen hL; serine protease; human lung