title: Regulation of nuclear scaffold protease activity by calcium.
abstract: Recent investigations have disclosed protease activity which is intimately associated with the nuclear scaffold. This protease activity shows a marked selectivity for lamins A/C, and from them may produce the 46-kDa NTPase thought to participate in nucleocytoplasmic RNA transport. Preliminary characterizations suggested that the protease activity might require Ca2+. In this report, we present evidence showing that nuclear scaffold protease activity is stringently regulated by Ca2+ within the physiologic range. Further, calmodulin antagonists such as calmidazolium and chlorpromazine produce marked inhibition of the protease activity, suggesting modulation by calmodulin or calmodulin-like factors.
authors.affiliation: Department of Pathology, George Washington University, Washington, D.C. 20037.
authors.forename: K R
authors.initials: KR
authors.lastname: Madsen
authors.forename: G
authors.initials: G
authors.lastname: Fiskum
authors.forename: G A
authors.initials: GA
authors.lastname: Clawson
mesh_terms: D000818:Animals; D002118:Calcium / Q000494:pharmacology / Q000502:physiology*; D002147:Calmodulin / Q000037:antagonists & inhibitors / Q000494:pharmacology; D002467:Cell Nucleus / Q000201:enzymology*; D002746:Chlorpromazine / Q000494:pharmacology; D004492:Edetic Acid / Q000494:pharmacology; D006706:Homeostasis; D007093:Imidazoles / Q000494:pharmacology; D007700:Kinetics; D008297:Male; D010447:Peptide Hydrolases / Q000378:metabolism*; D011480:Protease Inhibitors / Q000494:pharmacology*; D051381:Rats; D011919:Rats, Inbred Strains
chemical_list: D002147:Calmodulin; D007093:Imidazoles; D011480:Protease Inhibitors; C031938:calmidazolium; D004492:Edetic Acid; D010447:Peptide Hydrolases; D002118:Calcium; D002746:Chlorpromazine