Identification and characterization of the promoter region of the Nav1.7 voltage-gated sodium channel gene (SCN9A).
The Nav1.7 sodium channel plays an important role in pain and is also upregulated in prostate cancer. To investigate the mechanisms regulating physiological and pathophysiological Nav1.7 expression we identified the core promoter of this gene (SCN9A) in the human genome. In silico genomic analysis revealed a putative SCN9A 5' non-coding exon approximately 64,000 nucleotides from the translation start site, expression of which commenced at three very closely-positioned transcription initiation sites (TISs), as determined by 5' RACE experiments. The genomic region around these TISs possesses numerous core elements of a TATA-less promoter within a well-defined CpG island. Importantly, it acted as a promoter when inserted upstream of luciferase in a fusion construct. Moreover, the activity of the promoter-luciferase construct ostensibly paralleled endogenous Nav1.7 mRNA levels in vitro, with both increased in a quantitatively and qualitatively similar manner by numerous factors (including NGF, phorbol esters, retinoic acid, and Brn-3a transcription factor over-expression).
Diss
James K J
JK
Medical Molecular Biology Unit, Institute of Child Health, University College London, Guilford Street, London WC1N 1EH, UK. j.diss@ich.ucl.ac.uk
Calissano
Mattia
M
Gascoyne
Duncan
D
Djamgoz
Mustafa B A
MB
Latchman
David S
DS
D000818:Animals; D001483:Base Sequence; D045744:Cell Line, Tumor; D005091:Exons / Q000502:physiology; D005786:Gene Expression Regulation / Q000187:drug effects / Q000502:physiology*; D006801:Humans; D051379:Mice; D008969:Molecular Sequence Data; D062556:NAV1.7 Voltage-Gated Sodium Channel; D020932:Nerve Growth Factor / Q000494:pharmacology; D009447:Neuroblastoma; D011401:Promoter Regions, Genetic / Q000187:drug effects / Q000502:physiology*; D012333:RNA, Messenger / Q000378:metabolism; D015222:Sodium Channels / Q000235:genetics*; D024363:Transcription Initiation Site
D062556:NAV1.7 Voltage-Gated Sodium Channel; D012333:RNA, Messenger; C486866:SCN9A protein, human; D015222:Sodium Channels; D020932:Nerve Growth Factor