Temporally- and spatially-regulated transcriptional activity of the nicotinic acetylcholine receptor β4 subunit gene promoter

Abstract

Signaling through nicotinic acetylcholine (nACh) receptors underlies a diverse array of behaviors. In order for appropriate signaling to occur via nACh receptors, it is necessary for the genes encoding the receptor subunits to be expressed in a highly regulated temporal and spatial manner. Here we report a transgenic mouse approach to characterize the transcriptional regulation of the gene encoding the nACh receptor β4 subunit. nACh receptors containing this subunit play critical roles in both the central and peripheral nervous systems. We demonstrate that a 2.3-kilobase pair fragment of the β4 5′-flanking region is capable of directing reporter gene expression in transgenic animals. Importantly, the transcriptional activity of the promoter region is cell-type-specific and developmentally regulated and overlaps to a great extent with endogenous β4 mRNA expression. These data indicate that the 2.3-kilobase pair fragment contains transcriptional regulatory elements critical for appropriate β4 subunit gene expression. Keywords nicotinic receptor; gene expression; transcriptionSignaling through neuronal nicotinic acetylcholine (nACh) receptors underlies several fundamental biological processes both during development and in the adult (Albuquerque et al., 2009). In the central nervous system, presynaptic nACh receptors modulate release of most classical neurotransmitters including norepinephrine, ACh, glutamate and GABA (Albuquerque et al., 2009;Dani and Bertrand, 2007;Engelman and MacDermott, 2004). Postsynaptic nACh receptors are intimately involved in fast ACh-mediated synaptic transmission in addition to activity-dependent gene expression, which is critical for synaptic Publisher's Disclaimer: This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and review of the resulting proof before it is published in its final citable form. Please note that during the production process errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain. NIH Public Access Author ManuscriptNeuroscience. Author manuscript; available in PMC 2011 March 31. Dani and Bertrand, 2007;Hu et al., 2002;Ji et al., 2001). Within the peripheral nervous system, nACh receptors mediate fast excitatory transmission in most, if not all, autonomic ganglia and are involved in modulating visceral and somatic sensory transmission (Genzen et al., 2001;Hu and Li, 1997;Steen and Reeh, 1993;Sucher et al., 1990;Wang et al., 2002). More recently, numerous studies have revealed the expression of nACh receptors on non-neuronal cells and evidence is accumulating indicating that the receptors play crucial roles in signal transduction underlying many physiological processes outside the nervous system (Gahring and Rogers, 2006;Spindel, 2003;Wessler and Kirkpatrick, 2008). The importance of nACh receptor-mediated signaling is reflected ...

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Response to Transdermal Selegiline Smoking Cessation Therapy and Markers in the 15q24 Chromosomal Region

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A transcriptional regulatory element critical for CHRNB4 promoter activity in vivo

“…The 2,346-base pair SacI/HindIII fragment of the rat β4 subunit gene was excised from the pSGB4SH construct (Bruschweiler-Li et al, 2010) and used as the template for mutagenic polymerase chain reaction (PCR). For mutagenesis, the primers were designed to make 3 base substitutions in the CA box within the context of the 2.3-kb promoter fragment (Fig.…”

“…This regulatory element, deemed the CA box due to its nucleotide composition, is also the binding site for several transcription factors in vivo (Scofield et al, 2008). We recently demonstrated that a 2.3-kb fragment of the β4 promoter region containing the CA box is capable of directing cell-type specific and developmentally regulated expression of a reporter gene in vivo (Bruschweiler-Li et al, 2010). …”