The nucleotide sequence reported in this paper has been submitted to the GenBank with accession number AF222788.
Expression of the Helicoverpa cathepsin b-like proteinase during embryonic development †
Article first published online: 14 DEC 2004
Copyright © 2004 Wiley-Liss, Inc.
Archives of Insect Biochemistry and Physiology
Volume 58, Issue 1, pages 39–46, January 2005
How to Cite
Zhao, X.-F., An, X.-M., Wang, J.-X., Dong, D.-J., Du, X.-J., Sueda, S. and Kondo, H. (2005), Expression of the Helicoverpa cathepsin b-like proteinase during embryonic development . Arch. Insect Biochem. Physiol., 58: 39–46. doi: 10.1002/arch.20030
- Issue published online: 14 DEC 2004
- Article first published online: 14 DEC 2004
- Manuscript Accepted: 6 OCT 2004
- Manuscript Received: 10 DEC 2003
- Natural Science Foundation of China. Grant Numbers: 39870095, 30330070
- Helicoverpa armigera;
- cathepsin B-like proteinase;
- embryonic development
Cathepsin B-like proteinase from Helicoverpa armigera (HCB) was proposed as being involved in the degradation of yolk proteins during embryonic development. Recombinant HCB was expressed as a fusion protein with GST in Escherichia coli BL21 on the basis of its cDNA and purified to homogeneity. The fusion protein was cleaved with thrombin to generate a soluble protease with a mass of 37 kDa. A polyclonal antiserum against this recombinant protein, raised in the rabbit, recognized three isoforms of HCB in an ovary homogenate of this insect. Expression of this enzyme during embryonic development was studied using immunoblotting, immunohistochemistry and activity assay. It was found that HCB was expressed during embryonic development and that its proteolytic activity was detected from embryonic developmental eggs. The fact that HCB activity is observed in ovaries and developing eggs suggested that the enzyme had already been activated before embryonic development. Immunohistochemistry indicated that the enzyme was located in follicular cells, the sphere of yolk granules, and the fat bodies of female adult. These lines of evidence suggested strongly that HCB takes part in the degradation of yolk proteins during the development of embryo. Arch. Insect Biochem. Physiol. 58:39–46, 2005. © 2004 Wiley-Liss, Inc.