摘要
Cecropin A1 （CeeA1） promoter from Bombyx mori was cloned and character- ized to provide insight into the transcriptional control of this antimicrobial peptide gene upon immune challenges. Reporter gene assays demonstrated that both Escherichia coli and lipopolysaccharide could induce expression in BmE cells but B. bombyseptieus or peptidoglycan failed, and the induction pattern of the reporter gene was coincident with the endogenous CecAl. Analysis of deletion and mutation constructs revealed that the regulatory region was the κB motif located between -176 and -166, and no other pre- dicted elements on CecAl promoter affected its inducibility. Insertion of additional κB motifs increased the activity of CecAl promoter. Furthermore, binding of Relish to lob motif was confirmed by electrophoretic mobility shift assay. These findings indicate the regulatory mechanism of CecAl expression in IMD pathway and suggest an approach of engineering antimicrobial peptide promoter with enhanced activities that may lead to broad applications.
Cecropin A1 （CeeA1） promoter from Bombyx mori was cloned and character- ized to provide insight into the transcriptional control of this antimicrobial peptide gene upon immune challenges. Reporter gene assays demonstrated that both Escherichia coli and lipopolysaccharide could induce expression in BmE cells but B. bombyseptieus or peptidoglycan failed, and the induction pattern of the reporter gene was coincident with the endogenous CecAl. Analysis of deletion and mutation constructs revealed that the regulatory region was the κB motif located between -176 and -166, and no other pre- dicted elements on CecAl promoter affected its inducibility. Insertion of additional κB motifs increased the activity of CecAl promoter. Furthermore, binding of Relish to lob motif was confirmed by electrophoretic mobility shift assay. These findings indicate the regulatory mechanism of CecAl expression in IMD pathway and suggest an approach of engineering antimicrobial peptide promoter with enhanced activities that may lead to broad applications.
基金
This work was supported by grants from the National Basic Research Program of China （No. 2012CB 114600） and the National Natural Science Foundation of China （No. 31201854）.
