title: Human cyclin A is adenovirus E1A-associated protein p60 and behaves differently from cyclin B.
abstract: CYCLINS are proteins synthesized during each cell cycle and abruptly destroyed in each mitosis. Cyclins have been implicated in the induction of mitosis and are associated with the serine-threonine protein kinase p34cdc2 as components of mitosis promoting factor (MPF). On the basis of conserved sequence motifs cyclins can be divided into A or B types. We recently cloned a human cyclin B and showed that cyclin B expression is regulated transcriptionally and post-translationally during the cell cycle, and that cyclin B associates with p34cdc2. Here we report that human cyclin A messenger RNA and protein levels also vary during the cell cycle, and increase and decrease in advance of cyclin B levels. Cyclin A is associated with a protein of relative molecular mass 33,000 that is related to, but distinct from, p34cdc2, and this complex has histone H1 kinase activity in vitro. Cyclin A is identical to p60, a protein that associates with p34cdc2 in interphase cells and with adenovirus E1A in transformed cells.
authors: Molecular Biology and Virology Laboratory, Salk Institute for Biological Studies, San Diego, California 92138.
authors: J
authors: J
authors: Pines
authors: T
authors: T
authors: Hunter
mesh_terms: D017456:Adenovirus Early Proteins; D000260:Adenoviruses, Human / Q000235:genetics*; D002453:Cell Cycle; D016213:Cyclins; D004268:DNA-Binding Proteins / Q000235:genetics; D006367:HeLa Cells / Q000166:cytology / Q000378:metabolism; D006801:Humans; D007447:Invertebrate Hormones / Q000096:biosynthesis / Q000235:genetics* / Q000302:isolation & purification; D008715:Methionine / Q000378:metabolism; D008970:Molecular Weight; D009856:Oncogene Proteins, Viral / Q000235:genetics*; D010449:Peptide Mapping; D011499:Protein Processing, Post-Translational; D012333:RNA, Messenger / Q000235:genetics / Q000302:isolation & purification; D014158:Transcription, Genetic
chemical_list: D017456:Adenovirus Early Proteins; D016213:Cyclins; D004268:DNA-Binding Proteins; D007447:Invertebrate Hormones; D009856:Oncogene Proteins, Viral; D012333:RNA, Messenger; D008715:Methionine