Kaneko Yoichi, Furukawa Seiichi, Tanaka Hiromitsu, Yamakawa Minoru
Graduate School of Life and Enviromental Sciences, University of Tsukuba, Tsukuba, Ibaraki 305-8572, Japan.
Biosci Biotechnol Biochem. 2007 Sep;71(9):2233-41. doi: 10.1271/bbb.70212. Epub 2007 Sep 7.
Antimicrobial peptides, Enbocin and Gloverin isoforms from the silkworm Bombyx mori, were analyzed for expression of these peptide genes. Tissue-specific expression of Enbocin and Bmgloverin isoform genes was observed mainly in the fat body upon injection of Escherichia coli. Peptidoglycan and lipopolysaccharide triggered expression of these genes in vivo. On the other hand, lipid A activated Bmgloverin isoform genes but not Enbocin isoform genes. These results illustrate the fact that expression of Enbocin and Bmgloverin isoform genes is inducible by bacteria and that the effects of bacterial cell wall components on the activation of these peptide genes are not necessarily the same. In addition, selective activation of the Enbocin2, Bmgloverin2, and Bmgloverin4 genes by BmRelB rather than BmRelA was observed, providing additional evidence for the occurrence of selective activation of antimicrobial peptide genes by a Rel protein. These results suggest complex regulatory mechanisms in insect antimicrobial peptide genes by bacterial cell wall components.
对家蚕抗菌肽、恩波辛和格洛弗林异构体进行了这些肽基因表达的分析。注射大肠杆菌后，观察到恩波辛和Bmgloverin异构体基因的组织特异性表达主要在脂肪体中。肽聚糖和脂多糖在体内触发了这些基因的表达。另一方面，脂质A激活了Bmgloverin异构体基因，但未激活恩波辛异构体基因。这些结果表明，恩波辛和Bmgloverin异构体基因的表达可被细菌诱导，并且细菌细胞壁成分对这些肽基因激活的影响不一定相同。此外，观察到BmRelB而非BmRelA对恩波辛2、Bmgloverin2和Bmgloverin4基因的选择性激活，为Rel蛋白对抗菌肽基因发生选择性激活提供了额外证据。这些结果表明细菌细胞壁成分对昆虫抗菌肽基因有复杂的调控机制。
