Disease relevance of mAcR-60C

• Pretreatment of S2-DM1-TRPL cells with 10 microM atropine abolished Gd(3+)-insensitive Ca2+ influx triggered by carbamylcholine, but the response was not blocked by prior incubation with pertussis toxin [1].
• To test this hypothesis, Ca2+ signalling was examined in Fura-2-loaded Sf9 cells infected with baculovirus containing cDNA for the M5 muscarinic receptor alone (M5 cells) or in cells co-infected with both M5 and Trpl-containing baculoviruses (M5-Trpl cells) [2].

High impact information on mAcR-60C

• The receptor expressed in these cells exhibits the high-affinity binding for the antagonists quinuclidinyl benzilate and atropine expected of a muscarinic receptor [3].
• The binding characteristics of the expressed receptor were determined using transfected COS-7 cells, whereas the mAChR functional properties were analyzed using nuclearly injected Xenopus oocytes [4].
• Immunocytochemistry on fly sections demonstrated that the mAChR gene product was found in the nervous system and was not seen in skeletal muscle [4].
• The phylogeny and patterns of nucleotide substitutions in the visual pigment genes, adrenergic receptor genes, muscarinic receptor genes, and in the human mas oncogene were studied by comparing their DNA sequences [5].
• Using the Drosophila melanogaster S2 cell line, stably expressing a cloned muscarinic acetylcholine receptor (AChR), DM1, we have applied gene silencing by double-stranded RNA interference (RNAi) to knock down gene products involved in DM1-mediated calcium signalling [6].

Biological context of mAcR-60C

• The muscarinic receptor maps to the tip of the right arm of the second chromosome of the Drosophila genome [7].
• The staining of a discrete group of neurosecretory cells in the pars intercerebralis of the brain indicates a possible new role for this mAChR in the regulation of neurosecretion [8].
• Other evidence for muscarinic receptor subtypes which is examined includes: heterogeneous responses to classical muscarinic ligands and evidence for coupling of invertebrate muscarinic receptors to several different classes of second messenger systems [9].
• The nematode mAChR, consisted of 585 amino acids, displays a high degree of amino acid sequence homology to other invertebrate and vertebrate mAChRs [10].
• Comparison of the cDNA sequence with the corresponding genomic sequence reveals that the C. elegans mAChR gene contains ten introns, eight of them in the coding region [10].

Anatomical context of mAcR-60C

• We have stably co-expressed Drosophila TRPL with a Drosophila muscarinic acetylcholine receptor (DM1) in a Drosophila cell line (S2 cells) [1].
• Pharmacological profiles of the C. elegans mAChR expressed in Chinese hamster ovary (CHO) cells were shown to be similar to those of mammalian counterparts, indicating that ligand binding domains of the receptor have been conserved during evolution [10].
• Muscarinic receptors in brain membranes from honey bees, houseflies, and the American cockroach were identified by their specific binding of the non-selective muscarinic receptor antagonist [3H]quinuclidinyl benzilate ([3H]QNB) and the displacement of this binding by agonists as well as subtype-selective antagonists, using filtration assays [11].

Associations of mAcR-60C with chemical compounds

• Activation of DM1 receptor in S2-DM1-TRPL cells by 100 microM carbamylcholine induced Ca2+ release from an intracellular Ca2+ pool followed by a Gd(3+)-insensitive Ca2+ influx [1].
• Muscarinic receptor in Drosophila melanogaster demonstrated by binding of [3H]quinuclidinyl benzilate [12].
• Application of the cholinergic agonist carbamylcholine (100 microM) to transfected S2-DM1 cells expressing a Drosophila muscarinic acetylcholine receptor (DM1) emptied the InsP3-sensitive Ca2+ store but failed to affect the amplitude of alkalinization-evoked Ca2+ release [13].
• [3H]-QNB binding at this site was displaced by pirenzepine and methoctramine (Kis = 248 and 707 nM) closely matching the pharmacology of the cloned Drosophila mAChR [14].
• Carbamylcholine (CCh) and oxotremorine are potent agonists, whereas application of the vertebrate M1 mAChR agonist, McN-A-343, results in a weak response [15].

Regulatory relationships of mAcR-60C

• A cloned Drosophila muscarinic acetylcholine receptor (mAChR) has been stably expressed in a Drosophila cell line (S2) under the control of an inducible Drosophila metallothionein promoter [16].

Other interactions of mAcR-60C

• In an attempt to resolve this confusion we have explored the mechanism of activation of TRPL channels co-expressed with a PLC-specific muscarinic receptor in a Drosophila cell line (S2 cells) [17].
• Temporal and spatial expression patterns of a muscarinic acetylcholine receptor (Acr60C) and an octopamine/tyramine receptor (Octyr) were determined in Drosophila melanogaster using quantitative Northern analysis and in situ hybridization to tissue sections [18].

References