Disease relevance of Cha

• Synaptic activity was blocked by both pan-neuronal expression of tetanus toxin light chain (TeTxLC) and by reduction of acetylcholine (ACh) using a temperature-sensitive allele of choline acetyltransferase (Cha(ts2)) [1].
• A fusion protein containing a Drosophila choline acetyltransferase (ChAT) cDNA insert was purified from a lambda gtll lysate of Escherichia coli [2].
• Using a monoclonal antibody to choline acetyltransferase (ChAT), we have identified immunoreactive synaptic terminals in the neuropil regions of the cephalic ganglion of Drosophila melanogaster [3].

High impact information on Cha

• Consistent with results from cellular systems, we demonstrate that maximal levels of transactivation in vitro require both p300 and pCAF, as well as the cofactor acetyl CoA [4].
• These observations suggest that acetic acid is detoxified by the conversion of acetate into acetyl-CoA, a metabolic step also involved in ethanol detoxification [5].
• We have compared the amino acid sequences of proteins that are involved in acetylcholine (AcCho) metabolism and cholinergic neurotransmission: choline acetyltransferase (ChoAcTase), acetylcholinesterase (AcChoEase), and a neuronal alpha subunit of nicotinic AcCho receptor (AcChoR) [6].
• Expression of the choline acetyltransferase (ChAT) gene in Drosophila melanogaster is responsible for production of the neurotransmitter acetylcholine and is necessary for viability [7].
• In previous studies, we have shown that the regulatory region for normal ChAT expression is large and composed of multiple regulatory elements (Kitamoto et al., 1992; Kitamoto and Salvaterra, 1993) [7].

Chemical compound and disease context of Cha

• A cDNA for Drosophila choline acetyltransferase (EC 2.3.1.6; ChAT) was fused with a polyhistidine sequence and expressed in Escherichia coli [8].

Biological context of Cha

• Kinesin-2 differentially regulates the anterograde axonal transports of acetylcholinesterase and choline acetyltransferase in Drosophila [9].
• The normal in vitro expression pattern for ChAT and AChE can be altered by adding various cholinergic drugs to the culture medium during cell differentiation [10].
• Choline acetyltransferase (ChAT; acetyl-CoA:choline-O-acetyltransferase; EC 2.3.1.6) is the enzyme responsible for the synthesis of the neurotransmitter acetylcholine and is thus the genetic determinant of neurons with a cholinergic phenotype [11].
• When the integrity of the CoASAc binding site was investigated in the inactive mutants, the data suggested that the binding site in His393Leu-ChAT is disrupted but conserved in His426Leu-ChAT and His426Gln-ChAT [12].
• We have screened a Drosophila genomic library using a cRNA probe, transcribed from Drosophila ChAT cDNA, and isolated three independent clones representing all the exons of this gene [11].

Anatomical context of Cha

• All ChAT/VAChT-ir boutons form divergent synapses upon multitudinous surrounding Kenyon cell dendrites [13].
• The Drosophila cholinergic locus is composed of two distinct genetic functions: choline acetyltransferase (ChAT; EC 2.3.1.6), the enzyme catalyzing biosynthesis of neurotransmitter acetylcholine (ACh), and the vesicular ACh transporter (VAChT), the synaptic vesicle membrane protein which pumps transmitter into vesicles [14].
• This study presents evidence that large numbers of Drosophila cortical and primary sensory neurons contain the messenger RNA necessary for the production of ChAT, the acetylcholine-synthesizing enzyme [15].
• We demonstrate that the neuropils of the LAL and the TR-SOG are immunoreactive to ChAT and GABA [16].
• The photoreceptors have been shown previously to exhibit histamine-like immunoreactivity, but they also stain with a monoclonal antiserum raised against Drosophila choline acetyltransferase (ChAT), suggesting that the photoreceptors not only may contain histamine but also can synthesize acetylcholine [17].

Associations of Cha with chemical compounds

• Choline acetyltransferase and acetylcholine levels in Drosophila melanogaster: a study using two temperature-sensitive mutants [18].
• Acetylcholine (ACh) and choline levels were determined in formic acid-acetone extracts of individual fly heads, and the ACh levels showed the same variation with time at 32 degrees C as did the ChAT activity [18].
• The choline acetyltransferase (ChAT) reaction involves the transfer of the acetyl group of acetyl-CoA to choline, in which an active site histidine is believed to act as a general acid/base catalyst [12].
• The amino terminal sequence of the 13-kilodalton (kD) polypeptide present in purified Drosophila acetyl-CoA: choline-O-acetyltransferase (EC 2.3.1.6) was determined, and its position in the sequence of the intact enzyme was located [19].
• Immunoreactivity against choline acetyltransferase, gamma-aminobutyric acid, histamine, octopamine, and serotonin in the larval chemosensory system of Dosophila melanogaster [16].

Physical interactions of Cha

• AChE transport is constitutive while that of ChAT occurs in a brief pulse during third instar larva stage [9].
• Drosophila Kinesin II was shown to be essential for the axonal transport of choline acetyltransferase in a specific set of neurons [20].
• A POU homeo domain protein related to dPOU-19/pdm-1 binds to the regulatory DNA necessary for vital expression of the Drosophila choline acetyltransferase gene [7].

Regulatory relationships of Cha

• RNase protection analysis indicates that all Drosophila VAChT specific transcripts contain the shared first exon and suggests common transcriptional control for ChAT and VAChT [14].

Other interactions of Cha

• The results obtained in these studies are discussed with respect to data presented on the adult distribution of the cholinergic markers' AChE activity and ChAT immunoreactivity [21].
• Mutations in the kinesin-2 motor subunit Klp64D and separate siRNA-mediated knock-outs of all the three kinesin-2 subunits disrupt the ChAT and AChE transports, and these antigens accumulate in discrete nonoverlapping punctae in neuronal cell bodies and axons [9].
• Choline acetyltransferase enzyme activity, protein levels, mRNA, and a fluorescent cholinergic reporter gene are all decreased in olfactory neurons of acj6 mutants [22].
• A putative Drosophila melanogaster ortholog or paralog of peritrophin-55 (CG7714) was located within a 3458 bp intron of the Cha gene (choline-O-acetyltransferase), but on the opposite strand [23].
• Transcriptional analysis of chromatin assembled with purified ACF and dNAP1 reveals that acetyl-CoA is required for preinitiation complex assembly [24].

Analytical, diagnostic and therapeutic context of Cha

• Isoelectric focusing profiles of ChAT from both Chats mutants revealed enzymes with altered patterns compared to wild type, indicating that the mutations are most probably in the structural gene.(ABSTRACT TRUNCATED AT 250 WORDS)[18]
• Complementation tests with a Cha mutant allele and rescue experiments using a transgenic Vacht minigene have revealed that two of these three mutations are nonconditional lethal alleles of Vacht (Vacht(1) and Vacht(2) ) [25].
• Sequence analysis of a proteolyzed site in Drosophila choline acetyltransferase [19].
• Functional analysis of conserved histidines in choline acetyltransferase by site-directed mutagenesis [12].
• Localization of Drosophila neurons that contain choline acetyltransferase messenger RNA: an in situ hybridization study [15].

References