Novel Messenger RNA and Alternative Promoter for Murine Acetylcholinesterase

Abstract

A portion of the 5-flanking region of murine acetylcholinesterase was cloned from genomic DNA by 5-rapid amplification of genomic ends, identified in a mouse genomic library, and sequenced. Multiple potential binding sites for universal and tissue-specific transcription factors were suggestive of a promoter region within this DNA sequence. Potential promoter activity was confirmed by coupling the new sequence to the open reading frame of a luciferase reporter gene in transient expression experiments with nerve and muscle cells. 5-Rapid amplification of cDNA ends with templates from multiple sources revealed a novel transcription start site (at position ؊626, relative to translation start), located 32 bases downstream from a TATAA sequence. This start site appeared to mark a novel exon (1a) comprising 291 base pairs between positions ؊335 and ؊626, relative to the translation start. Supporting this conclusion, polymerase chain reactions with cDNA from mouse brain, heart, and other tissues, consistently amplified a transcript containing the exon 1a sequence fused to the invariant sequence beginning at position ؊22 in exon 2, but lacking exon 1. Northern blot analyses confirmed the in vivo expression of exon 1a-containing transcripts, especially in heart, brain, liver, and kidney. These results indicate that the murine acetylcholinesterase gene has a functioning alternative promoter that may influence expression of acetylcholinesterase in certain tissues.

Short‐ and long‐term influences of calcitonin gene‐related peptide on the synthesis of acetylcholinesterase in mammalian myotubes

“…This result is consistent with recent studies indicating that high levels of cyclic AMP stimulate the synthesis of AChE in avian myotubes (Choi et al, 1998). Moreover, cyclic AMP responsive element (CRE) sequences were found either in mouse (Atanasova et al, 1999) or human AChE genes (Ben Aziz-Aloya et al, 1993). Similarly, the human and chick AChE gene promoters were shown to be activated by cyclic AMP-dependent pathway (Wan et al, 2000;Choi et al, 2000), suggesting the involvement of CRE in mammals and avian AChE transcription.…”

Zebrafish Acetylcholinesterase Is Encoded by a Single Gene Localized on Linkage Group 7

“…We identified a canonical TATA box that contrasts with other cholinesterase genes that are devoid of this regulating element. However, a TATA box has been identified in the recently described murine AChE neuronal promoter (51). A TATA repeat was also found 32 bp upstream from the Torpedo AChE transcription start site.…”

“…Early Expression of mRNAs and Protein in Embryos-Tissue specificity and early expression of cholinesterases in mammals are due to specific transcription factor binding sites (50), alternative promoter usage (51), and intronic enhancers (52,53). In the zebrafish ache 5Ј non-coding region and first intron, no homology was detected with other ache genes.…”

Combinatorial Complexity of 5′ Alternative Acetylcholinesterase Transcripts and Protein Products

“…Two proximal human (18) and mouse (7,8) ACHE promoters have been described previously. In our current study we demonstrate that human and mouse ACHE genes contain at least four alternative first exons each of which at least one encodes an extended N terminus.…”

“…AChE pre-mRNA is subject to stimulus-induced 3Ј alternative splicing (6), and previous evidence has suggested that it is also subject to alternate promoter usage (7,8). We analyzed the genomic regions flanking the human and mouse ACHE genes and found an unexpected, evolutionarily conserved diversity of alternate exons at their 5Ј end.…”