Abstract:
:Double fertilization is a key innovation for the evolutionary success of angiosperms by which the two fertilized female gametes, the egg cell and central cell, generate the embryo and endosperm, respectively. The female gametophyte (embryo sac) enclosed in the sporophyte is derived from a one-celled haploid cell lineage. It undergoes successive events of mitotic divisions, cellularization, and cell specification to give rise to the mature embryo sac, which contains the two female gametes accompanied by two types of accessory cells, namely synergids and antipodals. How the cell fate of the central cell is specified has long been equivocal and is further complicated by the structural diversity of female gametophyte across plant taxa. Here, MADS-box protein AGL80 was verified as a transcriptional repressor that directly suppresses the expression of accessory cell-specific genes to specify the central cell. Further genetic rescue and phylogenetic assay of the AGL80 orthologs revealed a possible conserved mechanism in the Brassicaceae family. Results from this study provide insight into the molecular determination of the second female gamete cell in Brassicaceae.
journal_name
Proc Natl Acad Sci U S Aauthors
Zhang MX,Zhu SS,Xu YC,Guo YL,Yang WC,Li HJdoi
10.1073/pnas.1909465117subject
Has Abstractpub_date
2020-03-17 00:00:00pages
6231-6236issue
11eissn
0027-8424issn
1091-6490pii
1909465117journal_volume
117pub_type
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