A Kunitz-type proteinase inhibitor from the midgut of the ixodid tick, Haemaphysalis longicornis, and its endogenous target serine proteinase.
Although previous studies strongly suggested the involvement of serine proteases in blood digestion in the midgut of ticks, the regulating molecules of these proteinases are still unidentified. A novel Haemaphysalis longicornis Kunitz-type serine proteinase inhibitor with a single Kunitz-domain (HlMKI) has been identified and its co-localization with a midgut-derived serine proteinase (HlSP) within the epithelial cells has been demonstrated. Recombinant HlMKI inhibited the hydrolytic activity of HlSP, suggesting that HlMKI is a possible inhibitor of HlSP and may be part of a regulatory system of midgut serine proteinases.
Miyoshi
Takeharu
T
Laboratory of Parasitic Diseases, National Institute of Animal Health, 3-1-5 Kanondai, Tsukuba, Ibaraki, Japan.
Tsuji
Naotoshi
N
Islam
M Khyrul
MK
Alim
M Abdul
MA
Hatta
Takeshi
T
Yamaji
Kayoko
K
Anisuzzaman
Fujisaki
Kozo
K
D000595:Amino Acid Sequence; D000818:Animals; D003593:Cytoplasm / Q000201:enzymology; D004847:Epithelial Cells / Q000201:enzymology; D041981:Gastrointestinal Tract / Q000201:enzymology*; D026863:Ixodidae / Q000201:enzymology*; D008969:Molecular Sequence Data; D016415:Sequence Alignment; D057057:Serine Proteases / Q000378:metabolism*; D015842:Serine Proteinase Inhibitors / Q000378:metabolism*
D015842:Serine Proteinase Inhibitors; D057057:Serine Proteases