Retinoic acid induces cholinergic differentiation of cultured newborn rat sympathetic neurons

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cDNA cloning and complete sequence of porcine choline acetyltransferase: in vitro translation of the corresponding RNA yields an active protein.

A cDNA clone encoding the complete sequence of porcine choline acetyltransferase (ChoAcTase; acetyl-CoA: choline O-acetyltransferase, EC 2.3.1.6.) has been identified. A cDNA library, constructed from poly(A)+ RNA of ventral spinal cord, was screened with a mixture of eight oligonucleotides corresponding to the N-terminal sequence of pig brain ChoAcTase. Among five positive clones, one, pChAT-1, was identified as a ChoAcTase cDNA clone based on the following criteria. (i) This clone has an open reading frame coding for a protein of the size expected for ChoAcTase (640 amino acids). (ii) The amino acid composition deduced from the nucleotide sequence of this open reading frame matches that of purified porcine ChoAcTase. (iii) When subcloned in the T7 expression system, the corresponding RNA directs the synthesis in the rabbit reticulocyte lysate of a protein that is specifically immunoprecipitated by antibodies raised against ChoAcTase. (iv) Finally and most important, this corresponding RNA, when translated in the reticulocyte lysate, as well as in the Xenopus oocyte system, directs the synthesis of a protein displaying ChoAcTase activity. This activity is inhibited by the specific ChoAcTase inhibitor 4-(1-naphthylvinyl)pyridine. Comparison of porcine ChoAcTase sequence with that of Drosophila reveals 32% identity between these proteins, when the sequences are suitably aligned. pChAT-1 probe hybridizes with a porcine mRNA species that is at least 7000 nucleotides long, whereas the equivalent rat mRNA species is 3700 nucleotides long

Sodium butyrate modifies the stabilizing complexes of tyrosine hydroxylase mRNA.

Multiple mechanisms regulate the expression of the tyrosine hydroxylase (Th) gene, which encodes the rate-limiting enzyme in the biosynthesis of catecholamines. Sodium butyrate (SOB), a physiological histone deacetylase (HDAC) inhibitor, was reported to stimulate the Th gene promoter activity in reporter gene assays. However, the expression of the endogenous Th gene in PC12 cells was reported to be either stimulated or inhibited by SOB. Here, we report that SOB and other HDAC inhibitors drastically (up to 90%) and reversibly decrease the level of TH mRNA in PC12 cells. We also show that SOB does not influence the transcription initiation rate of the Th gene but perturbs the formation of protein-RNA complexes at the 3'UTR of the gene. Our results suggest that SOB inhibits the expression of the Th gene by destabilizing TH mRNAs

Tyrosine hydroxylase regulation in neurotransmission and neuroplasticity

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ILC3-derived acetylcholine promotes protease-driven allergic lung pathology

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