Premium
Krüppel homologue 1 acts as a repressor and an activator in the transcriptional response to juvenile hormone in adult mosquitoes
Author(s) -
Ojani R.,
Fu X.,
Ahmed T.,
Liu P.,
Zhu J.
Publication year - 2018
Publication title -
insect molecular biology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.955
H-Index - 93
eISSN - 1365-2583
pISSN - 0962-1075
DOI - 10.1111/imb.12370
Subject(s) - biology , juvenile hormone , repressor , chromatin immunoprecipitation , krüppel , rna interference , gene , activator (genetics) , transcription factor , zinc finger transcription factor , downregulation and upregulation , transcriptional regulation , transcription (linguistics) , microbiology and biotechnology , zinc finger , promoter , gene expression , genetics , rna , hormone , endocrinology , linguistics , philosophy
Krüppel homologue 1 (Kr‐h1) is a zinc finger transcription factor that is upregulated in insects by juvenile hormone (JH) in metamorphosis and adult reproduction. The molecular function of Kr‐h1 in reproduction remains largely unknown. Here we report that AaKr‐h1 functions as an important transcription regulator in adult female Aedes aegypti mosquitoes. The amount of AaKr‐h1 protein increases with rising JH levels after adult emergence, reaches its peak at 48 h after eclosion, then decreases gradually and disappears after blood feeding. RNA interference (RNAi)‐mediated depletion of AaKr‐h1 substantially reduced egg production after blood feeding. Using a chromatin immunoprecipitation cloning approach, we identified in vivo AaKr‐h1 binding sites in previtellogenic female mosquitoes. Binding of AaKr‐h1 to the target genes correlated with its protein abundance. Interestingly, RNAi experiments indicated that AaKr‐h1 played distinct roles when it bound to individual target genes. For example, depletion of AaKr‐h1 led to substantial upregulation of AAEL005545 and AAEL004444 , but also significantly decreased the expression of AAEL005957 and AAEL013177 when compared with the control mosquitoes. In summary, AaKr‐h1 directly binds to the regulatory regions of its target genes and acts as a transcriptional activator or a repressor in a promoter‐specific manner.