RRC ID 51234
Author Sukawa Y, Okamoto T.
Title Cell cycle in egg cell and its progression during zygotic development in rice.
Journal Plant Reprod
Abstract KEY MESSAGE:Rice egg is arrested at G1 phase probably by OsKRP2. After fusion with sperm, karyogamy, OsWEE1-mediated parental DNA integrity in zygote nucleus, zygote progresses cell cycle to produce two-celled embryo. In angiosperms, female and male gametes exist in gametophytes after the complementation of meiosis and the progression of nuclear/cell division of the haploid cell. Within the embryo sac, the egg cell is specially differentiated for fertilization and subsequent embryogenesis, and cellular programs for embryonic development, such as restarting the cell cycle and de novo gene expression, are halted. There is only limited knowledge about how the cell cycle in egg cells restarts toward zygotic division, although the conversion of the cell cycle from a quiescent and arrested state to an active state is the most evident transition of cell status from egg cell to zygote. This is partly due to the difficulty in direct access and analysis of egg cells, zygotes and early embryos, which are deeply embedded in ovaries. In this study, precise relative DNA amounts in the nuclei of egg cells, developing zygotes and cells of early embryos were measured, and the cell cycle of a rice egg cell was estimated as the G1 phase with a 1C DNA level. In addition, increases in DNA content in zygote nuclei via karyogamy and DNA replication were also detectable according to progression of the cell cycle. In addition, expression profiles for cell cycle-related genes in egg cells and zygotes were also addressed, and it was suggested that OsKRP2 and OsWEE1 function in the inhibition of cell cycle progression in egg cells and in checkpoint of parental DNA integrity in zygote nucleus, respectively.
Volume 31(1)
Pages 107-116
Published 2018-3-1
DOI 10.1007/s00497-017-0318-x
PII 10.1007/s00497-017-0318-x
PMID 29270910
MeSH Aphidicolin / pharmacology Cell Cycle* / drug effects Cell Cycle* / genetics Cell Nucleus Coloring Agents DNA, Plant / analysis Fluorescent Dyes Indoles Oryza / embryology* Oryza / genetics Transcriptome Zygote / cytology* Zygote / growth & development
IF 3.957
Times Cited 1
Arabidopsis / Cultured plant cells, genes rpc00031