Proteome analysis of silk gland proteins from the silkworm, Bombyx mori.
The silk gland of Bombyx mori is an organ specialized for the synthesis and secretion of silk proteins. We report here the resolution of silk gland proteins by 2-DE and the identification of many of those proteins. This was accomplished by dissecting the glands into several sections, with each exhibiting more than 400 protein spots by 2-DE, of which 100 spots were excised and characterized by in-gel digestion followed by PMF. Ninety-three proteins were tentatively identified. These were then categorized into groups involved in silk protein secretion, transport, lipid metabolism, defense, etc. Western blotting of a 2-DE gel using an antibody of the carotenoid binding protein confirmed the presence of this protein in the silk gland. Proteins including fibroin L-chain and P25 were found as multiple isoforms, some of which contained differential amounts of phosphate residues as analyzed by on-probe dephosphorylation. The current analysis contributes to our understanding of proteins expressed by the silk gland not only of the model lepidopteran B. mori, but also to proteins from other silk-producing insects such as Philosamia cynthia ricini.
Faculty of Agriculture, Institute of Genetic Resources, Kyushu University, Fukuoka, Japan.
Pingbo
P
Zhang
Yoichi
Y
Aso
Kohji
K
Yamamoto
Yutaka
Y
Banno
Yongqiang
Y
Wang
Kozo
K
Tsuchida
Yutaka
Y
Kawaguchi
Hiroshi
H
Fujii
D000818:Animals; D015153:Blotting, Western; D012831:Bombyx; D002338:Carotenoids / Q000737:chemistry; D015180:Electrophoresis, Gel, Two-Dimensional; D005349:Fibroins / Q000737:chemistry; D006023:Glycoproteins / Q000737:chemistry; D019476:Insect Proteins / Q000737:chemistry; D007525:Isoelectric Focusing; D010766:Phosphorylation; D040901:Proteomics / Q000379:methods*; D047011:Silk / Q000378:metabolism*; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; D014357:Trypsin / Q000494:pharmacology
D006023:Glycoproteins; D019476:Insect Proteins; C111320:P25 protein, Galleria mellonella; D047011:Silk; D002338:Carotenoids; D005349:Fibroins; D014357:Trypsin