Biochemistry and molecular biology of catecholamine neurons: a single gene or gene family hypothesis.
We postulate that the catecholamine synthesizing enzyme, tyrosine hydroxylase (TH), dopamine B-hydroxylase (DBH) and phenylethanolamine N-methyltransferase (PNMT) are coded for by similar gene coding sequence(s). This is based on the following observations: (1) proteolytic digestion of these enzymes produces similar peptides whose amino acid composition is nearly identical; (2) antibodies to each enzyme coprecipitate more than one of these enzymes from in vitro poly(A)mRNA translation products; (3) using hybrid selection analysis to positively identify the cDNA clones, we discovered that DBH cDNA clones cross-hybridize with PNMT mRNA, and PNMT cDNA cross-hybridize with DBH mRNA; (4) DNA hybridization analysis demonstrated that DBH and PNMT cDNA probes hybridized to several common restriction fragments of total cellular DNA. The evidence suggests that these enzymes are coded for by a single gene or linked genes coding for all catecholamine enzymes.
D000595:Amino Acid Sequence; D000818:Animals; D002395:Catecholamines / Q000096:biosynthesis*; D003429:Cross Reactions; D004299:Dopamine beta-Hydroxylase / Q000235:genetics*; D005815:Genetic Code; D006801:Humans; D009474:Neurons / Q000378:metabolism*; D009693:Nucleic Acid Hybridization; D010625:Phenylethanolamine N-Methyltransferase / Q000235:genetics*; D014176:Protein Biosynthesis; D014446:Tyrosine 3-Monooxygenase / Q000235:genetics*
D002395:Catecholamines; D014446:Tyrosine 3-Monooxygenase; D004299:Dopamine beta-Hydroxylase; D010625:Phenylethanolamine N-Methyltransferase