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A novel association between clustered NF-kappaB and C/EBP binding sites is required for immune regulation of mosquito Defensin genes.

ABSTRACT: A comparative analysis identified key cis-acting regulatory elements responsible for the temporal control of mosquito Defensin gene expression. The promoters of Anopheles gambiae Defensin 1 and two isoforms of Aedes aegypti Defensin A are up-regulated by immune challenge. This stimulated activity depends upon a cluster of three NF-kappaB binding sites and closely associated C/EBP-like motifs, which function as a unit for optimal promoter activity. Binding of NF-kappaB and C/EBP like transcription factors is confirmed by electrophoretic mobility shift assay, including supershifts with antibodies to C/EBP. KappaB-like motifs are abundant within antimicrobial peptide gene promoters and most are very closely associated with putative C/EBP binding sites. This novel association between NF-kappaB and C/EBP binding sites may, therefore, be of widespread significance.

SUBMITTER: Meredith JM

PROVIDER: S-EPMC1602061 | biostudies-literature | 2006 Aug

REPOSITORIES: biostudies-literature

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A novel association between clustered NF-kappaB and C/EBP binding sites is required for immune regulation of mosquito Defensin genes.

Meredith J M JM Munks R J L RJ Grail W W Hurd H H Eggleston P P Lehane M J MJ

Insect molecular biology 20060801 4

A comparative analysis identified key cis-acting regulatory elements responsible for the temporal control of mosquito Defensin gene expression. The promoters of Anopheles gambiae Defensin 1 and two isoforms of Aedes aegypti Defensin A are up-regulated by immune challenge. This stimulated activity depends upon a cluster of three NF-kappaB binding sites and closely associated C/EBP-like motifs, which function as a unit for optimal promoter activity. Binding of NF-kappaB and C/EBP like transcriptio ...[more]

PMID: 16907826

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