Abnormalities of spindle and cytokine behavior leading to the formation of meiotic restitution nuclei in intergeneric cereal hybrids
Mobile stages of meiosis have been analysed by visualizing the spindle in fertile cereal F1 hybrids. We describe four different mechanisms of the formation of restitution nuclei in meiotic division: (1) centripetal migration of telophase chromosome groups from the poles of a curved spindle at early telophase; (2) centripetal migration of the chromosome groups at late telophase when cell plate formation has failed; (3) preferable migration of univalents to one of the poles although spindle appearance is morphologically normal; and (4) in the absence of chromosome segregation where kinetochore fibers have failed to form. Copyright 1999 Academic Press.
Shamina
N
Department of Cell Differentiation, Institute of Cytology and Genetics, Siberian Branch of Russian Academy of Sciences, Novosibirsk, 630090, Russia.
Dorogova
N
Goncharov
N
Orlova
A
Trunova
S