Proteomic Analysis of the Silkworm (Bombyx mori L.) Hemolymph during Developmental Stage

Abstract

We utilized the proteomic approach to investigate the proteome of the fifth instar hemolymph during growth and development, and to improve the understanding of this important bioprocess and gene expression situation. A total of 25 μL of hemolymph was used for 2D analysis, and the separated proteins were visualized by silver staining and analyzed using the ImageMaster 2D software. The report showed as many as 241 of protein spots were expressed in the beginning of the fifth instar. Among them, most were concentrated in pI 3.5−6.5, which reached 76% of the total protein spots. As for the protein molecular sizes, 182 protein spots concentrated between 35 and 90 kDa, which comes to 75% of the total spots. When the larvae grow to the seventh day (total fifth instar duration was 9 days), 298 protein spots were visualized through 2D electrophoresis. Fifty-seven spots were newly expressed compared to the image of the first day in fifth instar. The results implied that these proteins are related to biosynthesis of silk protein and metamorphosis preparation from larva to pupa. In total, 19 protein spots including 6 special spots expressed in seventh day were analyzed through MALDI-TOF−MS. The relations between proteins and growth and development of silkworm were discussed. Keywords: silkworm (Bombyx mori L.) • hemolymph • proteomic analysis • 2D electrophoresis • MALDI-TOF−MS

Proteomic Analysis of Silk Gland Programmed Cell Death during Metamorphosis of the Silkworm Bombyx mori

“…Recently, this approach has been successfully used to profile the proteins expressed in different parts of the silk gland during fibroin synthesis, 25 and the proteome change of the hemolymph during the growth and development of the fifth instar larvae. 26 In the present study, we analyzed temporal changes in protein expression in the silk gland during PCD. Seventy-seven differentially accumulated protein spots were revealed by 2-DE, and 17 proteins were identified by mass spectrometry, including several apoptosis-related proteins, such as caspases, proteasome subunit, some upstream genes of ecdyson signal pathway, elongation factor, and heat shock protein, indicating that these proteins may play some roles in the PCD process of B. mori.…”

The Mulberry Silkworm—A New Source of Bioactive Proteins

“…The number of proteins ranges from 241 to 298 [28]. However, still few of them have been well-characterized and the number of silkworm protein structures in the protein data bank (PDB) is very low [29].…”

Molecular cloning, expression and characterization of a novel geneβ-N-acetylglucosaminidase from Bombyxmori

“…The specific bands corresponding to BmGlcNAcase2 were excised manually from the gel with a sterile scalpel and digested with trypsin according to Li's [10] method. The digested samples were analyzed by an ultraflex MALDI-TOF-TOF (BRUKER, GERMANY).…”