Two GC-rich boxes in huC promoter play distinct roles in controlling its neuronal specific expression in zebrafish embryos.
HuC, a vertebrate ortholog of Drosophila elav gene, encodes an RNA binding protein and is involved in early neurogenesis. Zebrafish huC is expressed in distinct neurons, including Rohon-Beard (RB) sensory neurons, interneurons and motoneurons, during primary neurogenesis, and in all neurons later during secondary neurogenesis. In this study, we identify two GC-rich box elements, proximal GC (p-GC) box from -172 to -149 and distal GC (d-GC) box from -218 to -208, in zebrafish huC promoter. Using transgenic approach, we demonstrate that deletion of the p-GC box from the promoter results in loss of expression of the reporter GFP in neurons while deletion of the d-GC box leads to GFP expression only in dorsal RB sensory neurons. These results suggest that the p-GC box alone confers transcriptional activity of huC promoter in primary RB neurons and the d-GC is required for huC transcription in the full spectrum of spinal cord neurons. Further studies are needed to identify specific Sp1-like transcription factors that bind to these GC boxes and activate huC transcription.
Protein Science Laboratory of Ministry of Education of China, Department of Biological Sciences and Biotechnology, Tsinghua University, Beijing 100084, China.
Chengtian
C
Zhao
Xinjun
X
He
Chenxi
C
Tian
Anming
A
Meng
D000818:Animals; D030801:Animals, Genetically Modified; D051959:ELAV Proteins / Q000235:genetics* / Q000378:metabolism*; D000067778:ELAV-Like Protein 3; D004625:Embryo, Nonmammalian / Q000196:embryology / Q000378:metabolism; D020862:GC Rich Sequence / Q000235:genetics*; D018507:Gene Expression Regulation, Developmental; D017930:Genes, Reporter / Q000235:genetics; D008969:Molecular Sequence Data; D009474:Neurons / Q000378:metabolism*; D009928:Organ Specificity; D011401:Promoter Regions, Genetic / Q000235:genetics*; D016329:Sp1 Transcription Factor / Q000378:metabolism; D015027:Zebrafish / Q000196:embryology* / Q000235:genetics / Q000378:metabolism*; D029961:Zebrafish Proteins / Q000235:genetics* / Q000378:metabolism*
D051959:ELAV Proteins; D000067778:ELAV-Like Protein 3; D016329:Sp1 Transcription Factor; D029961:Zebrafish Proteins; C088635:elavl3 protein, zebrafish