RRC ID 3601
著者 Mah AK, Armstrong KR, Chew DS, Chu JS, Tu DK, Johnsen RC, Chen N, Chamberlin HM, Baillie DL.
タイトル Transcriptional regulation of AQP-8, a Caenorhabditis elegans aquaporin exclusively expressed in the excretory system, by the POU homeobox transcription factor CEH-6.
ジャーナル J Biol Chem
Abstract Due to the ever changing environmental conditions in soil, regulation of osmotic homeostasis in the soil-dwelling nematode Caenorhabditis elegans is critical. AQP-8 is a C. elegans aquaporin that is expressed in the excretory cell, a renal equivalent tissue, where the protein participates in maintaining water balance. To better understand the regulation of AQP-8, we undertook a promoter analysis to identify the aqp-8 cis-regulatory elements. Using progressive 5' deletions of upstream sequence, we have mapped an essential regulatory region to roughly 300 bp upstream of the translational start site of aqp-8. Analysis of this region revealed a sequence corresponding to a known DNA functional element (octamer motif), which interacts with POU homeobox transcription factors. Phylogenetic footprinting showed that this site is perfectly conserved in four nematode species. The octamer site's function was further confirmed by deletion analyses, mutagenesis, functional studies, and electrophoretic mobility shift assays. Of the three POU homeobox proteins encoded in the C. elegans genome, CEH-6 is the only member that is expressed in the excretory cell. We show that expression of AQP-8 is regulated by CEH-6 by performing RNA interference experiments. CEH-6's mammalian ortholog, Brn1, is expressed both in the kidney and the central nervous system and binds to the same octamer consensus binding site to drive gene expression. These parallels in transcriptional control between Brn1 and CEH-6 suggest that C. elegans may well be an appropriate model for determining gene-regulatory networks in the developing vertebrate kidney.
巻・号 282(38)
ページ 28074-86
公開日 2007-9-21
DOI 10.1074/jbc.M703305200
PII S0021-9258(20)58704-8
PMID 17660295
MeSH Animals Aquaporins / metabolism* Aquaporins / physiology Base Sequence Caenorhabditis elegans Caenorhabditis elegans Proteins / metabolism Caenorhabditis elegans Proteins / physiology* Computational Biology DNA Primers / chemistry Homeodomain Proteins / metabolism Homeodomain Proteins / physiology* Kidney / metabolism Molecular Sequence Data Nerve Tissue Proteins / metabolism Neurons / metabolism POU Domain Factors / metabolism Sequence Homology, Nucleic Acid Transcription Factors / metabolism Transcription, Genetic
IF 4.238
引用数 23
WOS 分野 BIOCHEMISTRY & MOLECULAR BIOLOGY
リソース情報
線虫 tm1919