Cloning of a Xenopus laevis muscarinic receptor encoded by an intronless gene.
The Xenopus laevis oocyte has endogenous sites that bind muscarinic agonists, which have been pharmacologically characterized as M3 and/or M1 receptor subtypes. In order to define the molecular identify of the receptor protein we have analyzed a Xenopus oocyte cDNA library and cloned a 2.9 kb cDNA fragment encoding a muscarinic receptor (xMR). The deduced amino acid sequence reveals a protein of 484 residues with an apparent molecular weight of 54,188 Da. Amino acid comparison with previously cloned mammalian muscarinic receptors showed a 78% identity with the human m4 subtype, presenting at the same time clustered differences within the amino-terminal region and third intracellular loop Genomic Southern analysis displayed the presence of one main gene belonging to this subtype, and the PCR analysis revealed an intronless gene.
Herrera
L
L
Departamento de Fisiopatología, Facultad Ciencias Biológicas, Universidad de Concepion, Chile.
Carvallo
P
P
Antonelli
M
M
Olate
J
J
D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D003001:Cloning, Molecular; D018076:DNA, Complementary; D005796:Genes / Q000235:genetics*; D006801:Humans; D007438:Introns; D008969:Molecular Sequence Data; D008970:Molecular Weight; D009865:Oocytes; D016366:Open Reading Frames / Q000235:genetics; D011976:Receptors, Muscarinic / Q000737:chemistry / Q000235:genetics*; D016415:Sequence Alignment; D017422:Sequence Analysis, DNA; D017386:Sequence Homology, Amino Acid; D014982:Xenopus laevis / Q000235:genetics
D018076:DNA, Complementary; D011976:Receptors, Muscarinic