Abstract
A defensin-like gene, BmdefA, was rediscovered in the silkworm genome and expressed sequence tags databases. The open reading frame of BmdefA encodes a prepropeptide consisting of a 22-residue signal peptide, a 34-residue propeptide, and a 36-residue mature peptide with a molecular mass of 4.0 kDa. The mature peptide possesses the characteristic six-cysteine motif of insect defensins, and its predicted isoelectric point is 4.12, indicating it is a novel anionic defensin. An intron is present in BmdefA and several cis-regulatory elements are in the regulating region. It is transcribed constitutively at a high level in the hemocyte, silk gland, head, and ovary of the silkworm larvae, and in the fat body of early-stage pupae and moth. BmdefA is also strongly induced by immune challenge. These results suggest that BmdefA plays an important role in both immunity and metamorphosis.
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Abbreviations
- AMP:
-
Antimicrobial peptide
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Acknowledgments
This work was supported by (1) Grant-in-Aid for Global COE Program by the Ministry of Education, Culture, Sports, Science, and Technology, Japan, (2) Grant-in-Aid for Scientific Research (B) (No. 18380041) by Japan Society for the Promotion of Science, Japan, and (3) The Fund for Foreign Scholars in University Research and Teaching Programs (No. B07045), funded by the Ministry of Education and State Administration of Foreign Experts Affairs, P.R. China. We are indebted to the Division of Gene Research, Research Center for Human and Environmental Sciences, Shinshu University, for providing facilities.
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Hongxiu Wen and Xiqian Lan contributed equally to this work and should be considered co-first authors.
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Wen, H., Lan, X., Cheng, T. et al. Sequence structure and expression pattern of a novel anionic defensin-like gene from silkworm (Bombyx mori). Mol Biol Rep 36, 711–716 (2009). https://doi.org/10.1007/s11033-008-9233-4
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DOI: https://doi.org/10.1007/s11033-008-9233-4