title: Peptidylglycine-alpha-amidating monooxygenase activity and protein are lower in copper-deficient rats and suckling copper-deficient mice.
abstract: Peptidylglycine-alpha-amidating monooxygenase (PAM) is a copper-dependent enzyme involved in peptide posttranslational activation. Dietary Cu deficiency (Cu-) was studied to determine if lower PAM activity was due to reduction in protein or cofactor limitation. PAM activity was lower in cardiac atria of Cu- rats than Cu-adequate (Cu+) rats and there was a 50% equivalent reduction in PAM protein. No reduction in Cu- rat midbrain PAM protein was detected although PAM activity was reduced 40%. In 12-day-old (P12) mouse pups derived from dams that began Cu deficiency on day 7 of gestation, there was a parallel reduction in brain PAM activity and protein of 40-50%. PAM mRNA levels assessed in atria and brains from Cu+ and Cu- rats and mice were not altered by dietary treatment, suggesting a posttranscriptional mechanism for lower PAM protein when Cu is limiting in the cell, perhaps due to enhanced apoprotein turnover.
authors.affiliation: Department of Biochemistry and Molecular Biology, University of Minnesota Medical School Duluth, 1035 University Drive, Duluth, MN 55812, USA. jprohask@d.umn.edu
authors.forename: Joseph R
authors.initials: JR
authors.lastname: Prohaska
authors.forename: Anna A
authors.initials: AA
authors.lastname: Gybina
authors.forename: Margaret
authors.initials: M
authors.lastname: Broderius
authors.forename: Bruce
authors.initials: B
authors.lastname: Brokate
mesh_terms: D000818:Animals; D000833:Animals, Suckling; D003300:Copper / Q000172:deficiency*; D005260:Female; D015870:Gene Expression; D006325:Heart Atria / Q000378:metabolism; D008297:Male; D008636:Mesencephalon / Q000378:metabolism; D051379:Mice; D006899:Mixed Function Oxygenases / Q000235:genetics / Q000378:metabolism*; D009097:Multienzyme Complexes / Q000235:genetics / Q000378:metabolism*; D011247:Pregnancy; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D051381:Rats; D017207:Rats, Sprague-Dawley
chemical_list: D009097:Multienzyme Complexes; D012333:RNA, Messenger; D003300:Copper; D006899:Mixed Function Oxygenases; C035189:peptidylglycine monooxygenase