ISSN:
0739-4462
Keywords:
Manduca
;
tobacco hornworm
;
scolexin
;
immunity
;
insect defense
;
hemolymph proteins
;
Chemistry
;
Food Science, Agricultural, Medicinal and Pharmaceutical Chemistry
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Biology
Notes:
The immune protein, scolexin, a bacteria-induced, larva-specific protein from Manduca sexta, was shown to exist in the hemolymph in two isoelectric forms designated herein as scolexin-1 and scolexin-2 (native Mr ∼ 72 kd). These two charge isomers appeared to share the same amino acid composition. Scolexin is composed of two subunits (peptide Mr ∼ 36 kd) that possess the same N-terminus. Scolexin-2 was subjected to glycosyl composition analysis, revealing the presence of galactose, glucose, mannose, xylose, and sialic acid residues. Hybridization of epidermal RNA with oligonucleotides deduced from the scolexin N-terminal sequence showed a continuous decline in mRNA following day 0 of the 5th larval instar. By employing in vitro protein labelling, it was found that organ cultures of the epidermis from immune larvae showed a greater ability over that of naive epidermal cultures to synthesize scolexin; these data reflected the inducible response seen in the hemolymph, and confirm other data indicating that the epidermis is an important site of scolexin biosynthesis. © 1995 Wiley-Liss, Inc.
Additional Material:
5 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/arch.940290305
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