Choline acetyltransferase and acetylcholine in Xenopus oocytes injected with mRNA from the electric lobe of Torpedo.
AUTOR(ES)
Gundersen, C B
RESUMO
Xenopus oocytes were injected with poly(A)+ mRNA obtained from the electric lobes of Torpedo marmorata and Torpedo ocellata, which contain the cell bodies of the neurons that innervate the electric organs. The electric lobe mRNA preparation induces the oocytes to synthesize a catalytically active form of the enzyme choline acetyltransferase (EC 2.3.1.6). Enzymatic activity is found almost exclusively in the cytoplasmic fraction of injected, but not control, oocytes. Evidence is presented that distinguishes between the induced choline acetyltransferase activity and an intrinsic carnitine acetyltransferase activity present in the oocytes. This latter enzyme is associated principally with particulate fractions of the oocyte. The level of acetylcholine, which accumulates in mRNA-injected oocytes, is relatively insensitive to pharmacological manipulations that alter the acetylcholine content of other cells. These results show that Xenopus oocytes may be used advantageously to study functional properties of polypeptides associated with presynaptic elements in the nervous system.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=397090Documentos Relacionados
- Expression of an omega-conotoxin-sensitive calcium channel in Xenopus oocytes injected with mRNA from Torpedo electric lobe.
- Separate fractions of mRNA from Torpedo electric organ induce chloride channels and acetylcholine receptors in Xenopus oocytes.
- Biosynthesis and secretion of catalytically active acetylcholinesterase in Xenopus oocytes microinjected with mRNA from rat brain and from Torpedo electric organ.
- Incorporation of acetylcholine receptors and Cl- channels in Xenopus oocytes injected with Torpedo electroplaque membranes.
- Characterization of voltage-dependent calcium channels expressed in Xenopus oocytes injected with mRNA from rat heart.
