title: Characterization of the cDNA corresponding to a phosphoprotein (p43) intermediary in the action of ACTH.
abstract: We have previously isolated and partially-sequenced a soluble phosphoprotein (p43) that acts as intermediary in the stimulation of steroid synthesis. In this report we have used synthetic peptides whose sequences match those obtained from p43 to generate antipeptide antibodies and show that these antibodies bind to purified p43 protein as determined by immunoblot analysis. The presence of p43 was detected by Western blot in both steroidogenic and non-steroidogenic tissues. One of the antibodies was also used to purify p43 on immunoaffinity chromatography columns. Proteins eluting from affinity columns produce a twelve-fold stimulation of progesterone synthesis. This effect was blocked by the use of an inhibitor of phospholipase A2. These results suggest the involvement of p43 in transducing the adrenocorticotropin signal to mitochondria in zona fasciculata cells. We also describe a partial cDNA clone with a predicted amino acid sequence that matches the sequences of the internal peptides of p43.
authors.affiliation: Department of Biochemistry, School of Medicine, University of Buenos Aires, Argentina.
authors.forename: C
authors.initials: C
authors.lastname: Finkielstein
authors.forename: C
authors.initials: C
authors.lastname: Cymeryng
authors.forename: C
authors.initials: C
authors.lastname: Paz
authors.forename: I
authors.initials: I
authors.lastname: Neuman
authors.forename: L
authors.initials: L
authors.lastname: Dada
authors.forename: F
authors.initials: F
authors.lastname: Cornejo Maciel
authors.forename: P G
authors.initials: PG
authors.lastname: Mele
authors.forename: C F
authors.initials: CF
authors.lastname: Mendez
authors.forename: P
authors.initials: P
authors.lastname: Maloberti
authors.forename: A R
authors.initials: AR
authors.lastname: Solano
authors.forename: B P
authors.initials: BP
authors.lastname: Schimmer
authors.forename: E J
authors.initials: EJ
authors.lastname: Podestá
mesh_terms: D000324:Adrenocorticotropic Hormone / Q000494:pharmacology*; D000595:Amino Acid Sequence; D000818:Animals; D015153:Blotting, Western; D002846:Chromatography, Affinity; D018076:DNA, Complementary / Q000737:chemistry*; D004591:Electrophoresis, Polyacrylamide Gel; D015151:Immunoblotting; D008969:Molecular Sequence Data; D010446:Peptide Fragments / Q000737:chemistry / Q000276:immunology; D010750:Phosphoproteins / Q000737:chemistry / Q000235:genetics* / Q000494:pharmacology; D010766:Phosphorylation; D011374:Progesterone / Q000096:biosynthesis; D051381:Rats; D015383:Zona Fasciculata / Q000737:chemistry*
chemical_list: D018076:DNA, Complementary; D010446:Peptide Fragments; D010750:Phosphoproteins; D011374:Progesterone; D000324:Adrenocorticotropic Hormone