The transcriptional repressor REST is a critical regulator of the neurosecretory phenotype.
Release of distinct cellular cargoes in response to specific stimuli is a process fundamental to all higher eukaryotes and controlled by the regulated secretory pathway (RSP). However, the mechanism by which genes involved in the RSP are selectively expressed, leading to the establishment and appropriate functioning of regulated secretion remaining largely unknown. Using the rat pheochromocytoma cell line PC12, we provide evidence that, by controlling expression of many genes involved in the RSP, the transcriptional repressor REST can regulate this pathway and hence the neurosecretory phenotype. Introduction of REST transgenes into PC12 cells leads to the repression of many genes, the products of which are involved in regulated secretion. Moreover, chromatin immunoprecipitation assays show that many of the repressed genes recruit the recombinant REST protein to RE1 sites within their promoters and abrogation of REST function leads to reactivation of these transcripts. In addition to the observed transcriptional effects, PC12 cells expressing REST have fewer secretory granules and a reduction in the ability to store and release noradrenaline. Furthermore, an important trigger for synaptic release, influx of calcium through voltage-operated calcium channels, is compromised. This is the first demonstration of a transcription factor that directly controls expression of many major components of the RSP and provides further insight into the function of REST.
Bruce
Alexander W
AW
Institute of Membrane and Systems Biology, Faculty of Biological Sciences, University of Leeds, Leeds, UK. awb@sanger.ac.uk
Krejcí
Alena
A
Ooi
Lezanne
L
Deuchars
James
J
Wood
Ian C
IC
Dolezal
Vladimír
V
Buckley
Noel J
NJ
D000818:Animals; D015220:Calcium Channels / Q000378:metabolism; D020869:Gene Expression Profiling; D005786:Gene Expression Regulation; D009489:Neurosecretion / Q000235:genetics*; D009638:Norepinephrine / Q000037:antagonists & inhibitors / Q000378:metabolism; D020411:Oligonucleotide Array Sequence Analysis; D016716:PC12 Cells / Q000145:classification / Q000378:metabolism / Q000648:ultrastructure; D010641:Phenotype; D051381:Rats; D011994:Recombinant Proteins / Q000378:metabolism; D012097:Repressor Proteins / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism / Q000502:physiology*; D022142:Secretory Vesicles / Q000648:ultrastructure; D014157:Transcription Factors / Q000037:antagonists & inhibitors / Q000378:metabolism / Q000502:physiology*; D014158:Transcription, Genetic / Q000502:physiology; D000099229:RE1-Silencing Transcription Factor
D015220:Calcium Channels; D009638:Norepinephrine; D011994:Recombinant Proteins; D012097:Repressor Proteins; D014157:Transcription Factors; D000099229:RE1-Silencing Transcription Factor