Presence of mRNA of muscle nicotinic acetylcholine receptor subunits and an epsilon-subunit splice variant in the mouse brain

Abstract

Transcripts encoding for alpha 1, beta 1, delta, gamma and epsilon (and its splice variant epsilon(S)) subunits of the muscle-type nicotinic acetylcholine receptor (nAChR) were assessed using reverse transcription followed by polymerase chain reaction (RT-PCR) assays, with RNA extracted from the mouse skeletal muscle (diaphragm) and brain regions (cortex, hippocampus and cerebellum). the presence of alpha 1, beta 1, delta, gamma, epsilon and epsilon(S) transcripts was confirmed in the diaphragm muscle, used as positive control. mRNAs coding for muscle alpha 1, beta 1, delta, epsilon, epsilon(S), but not gamma subunits, were detected in adult mouse brain regions. An epsilon-subunit sequence variant, named epsilon(t), was also detected in all brain regions examined, but not in skeletal muscle. This new epsilon-subunit splice variant lacks a 115 bp cassette corresponding to exon 8 in the first intracellular transmembrane domain of the subunit, leading to a truncated protein. the data provide evidence for the presence of muscle-type nAChR subunits in the mouse central nervous system. (C) 2009 Elsevier Inc. All Fights reserved.