The roles of Drosophila cyclins A and B in mitotic control

Cell. 1990 May 4;61(3):535-47. doi: 10.1016/0092-8674(90)90535-m.


We have cloned, sequenced, and characterized the expression of a Drosophila cyclin B gene. The independent evolutionary conservation of A- and B-type cyclins implies that they have distinct roles. Indeed, in mutant embryos deficient in cyclin A, cells that accumulate only cyclin B do not enter mitosis. Thus, in vivo, cyclin B is not sufficient for mitosis. Furthermore, we find that the two cyclins are coexpressed in all proliferating cells throughout development. Though lacking a formal demonstration that cyclin B is essential as it is in other organisms, we propose that each of these proteins fulfills a distinct and essential role in the cell cycle.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Amino Acid Sequence
  • Animals
  • Antibodies
  • Base Sequence
  • Biological Evolution
  • Cell Cycle
  • Cloning, Molecular
  • Cyclins
  • Drosophila / cytology
  • Drosophila / embryology
  • Drosophila / genetics*
  • Embryo, Nonmammalian / cytology
  • Gene Expression
  • Genes
  • Insect Hormones / genetics*
  • Insect Hormones / isolation & purification
  • Insect Hormones / physiology
  • Interphase
  • Invertebrate Hormones / genetics*
  • Invertebrate Hormones / isolation & purification
  • Invertebrate Hormones / physiology
  • Mitosis*
  • Molecular Sequence Data
  • Mutation
  • Nucleic Acid Hybridization
  • Sequence Homology, Nucleic Acid


  • Antibodies
  • Cyclins
  • Insect Hormones
  • Invertebrate Hormones

Associated data

  • GENBANK/M33192