Canadian Forest Service Publications
Cloning, expression and localization of a trypsin-like serine protease in the spruce budworm. 2009. He, W.-Y.; Zheng, Y.-P.; Tang, L.; Zheng, S.-C.; Béliveau, C.; Doucet, D.; Cusson, M.; Feng, Q.L. Insect Sci. 16: 455-464.
Available from: Great Lakes Forestry Centre
Catalog ID: 31063
A trypsin-like molting-related serine protease cDNA (Cf MRSP) was cloned from the spruce budworm, Choristoneura fumiferana. The full-length Cf MRSP complementary DNA (cDNA) encoded a 43 kDa protein that contained a trypsin-like serine protease catalytic domain, but no clip domain. The C-terminal extension contained five cystein residues, which may allow the protein to form a homodimer through interchain disulfide bonds and regulate the activity of Cf MRSP. Phylogenetic tree analysis showed that Cf MRSP clusters with lepidopteran homologues such as serine protease 1 of Lonomia obliqua, hemolymph proteinase 20 (HP20), pattern recognition serine proteinase precursor (ProHP14) and a trypsin-like protein of Manduca sexta. Northern blot analysis of developmental expression of Cf MRSP indicated that its transcripts were found primarily in the epidermis and were produced during all of the tested stadia, from 4th instar larvae to pupae, but increased levels of Cf MRSP transcripts were always found after each molt. A high level of the protein was found in the epidermis by immunohistochemistry analysis. Altogether these data suggest that Cf MRSP plays a role in the epidermis during molting and metamorphosis.