[Meiosis-like reduction in the culture system for somatic embryogenesis of Arabidopsis thaliana].
The somatic meiosis-like reduction was observed in some cells in the embryogenic calli of Arabidopsis thaliana. One type was somatic chromosome reductional grouping, in which the chromosomes in a cell either separated into two groups, or separated into more than two groups at prophase or metaphase. The chromosomes separated directly, the morphology of the chromosomes did not show any role of the spindle fibers. Chromosome reductional grouping happened more frequently in polyploid cells. The other type was somatic meiossi which was analogous to that existed in the process of gametogenesis, and characterized by the pairing and synapsis of homologues chromosomes. In the embryogenic calli cultured on dedifferentiation medium, about 3% of the observed cells contained haploid number of chromosomes, while the tetrad cells occurred at a frequency of about 4%. The somatic meiosis-like reduction could result in the recombination of chromosomes in the cells generated by these processes. The roles of somatic meiosis-like reduction in the somatic embryogenesis and somaclonal variations were discussed.
Chen
Y H
YH
Institute of Genetics, Chinese Academy of Sciences, Beijing 100101, China.
Zhang
L H
LH
Geng
Y X
YX
Chen
Z H
ZH
D017360:Arabidopsis / Q000235:genetics* / Q000502:physiology; D008540:Meiosis