Rearrangement of nuclear calmodulin during proliferative liver cell activation.
Calmodulin increases about three-fold in rat liver nuclei after partial hepatectomy. The increase is maximal after 24 hours, when DNA synthesis is also maximal. During the same time re-distribution of calmodulin within the nuclear structure takes place, leading to its association with the nuclear matrix. Incubation of normal rat liver nuclei with Ca2+ induces association of calmodulin with the matrix, indicating that the re-distribution of calmodulin during the replicative period is related to the increase in nuclear Ca2+. The nuclear matrix contains several calmodulin binding proteins of which one, having Mr of 130 kDa, has been identified as myosin light chain kinase (MLCK). Three acceptor proteins, having Mr of 120, 65, and 60 kDa decrease 24 hours after partial hepatectomy, MLCK and a protein of Mr 150 kDa instead increase.
Serratosa
J
J
Departamento de Biologia Celular, Facultad de Medicina, Universidad de Barcelona, Spain.
Pujol
M J
MJ
Bachs
O
O
Carafoli
E
E
D000818:Animals; D002118:Calcium / Q000494:pharmacology; D002147:Calmodulin / Q000378:metabolism*; D002148:Calmodulin-Binding Proteins / Q000378:metabolism; D002455:Cell Division; D002467:Cell Nucleus / Q000378:metabolism*; D004247:DNA / Q000096:biosynthesis; D006498:Hepatectomy; D007700:Kinetics; D008099:Liver / Q000187:drug effects / Q000378:metabolism* / Q000648:ultrastructure; D008297:Male; D008970:Molecular Weight; D009219:Myosin-Light-Chain Kinase / Q000378:metabolism; D051381:Rats; D011919:Rats, Inbred Strains
D002147:Calmodulin; D002148:Calmodulin-Binding Proteins; D004247:DNA; D009219:Myosin-Light-Chain Kinase; D002118:Calcium