Activation of CYCD7;1 in the central cell and early endosperm overcomes cell‐cycle arrest in the Arabidopsis female gametophyte, and promotes early endosperm and embryo development

• DOI: 10.1111/tpj.12957
• Publication Date: 2015-08-11T05:25:35Z
• Authors: Emily Sornay; Céline Forzani; Manuel Forero‐Vargas; Walter Dewitte; James A.H. Murray
• Keywords: 580; Ovule; 0301 basic medicine; 570; 0303 health sciences; Arabidopsis Proteins; [SDV]Life Sciences [q-bio]; central cell; Arabidopsis; Original Articles; Cell Cycle Checkpoints; Endosperm; D-type cyclins; endosperm; [SDV] Life Sciences [q-bio]; QH301; 03 medical and health sciences; Gene Expression Regulation, Plant; Seeds; cell cycle; seed size

In angiosperms, double fertilization of the egg and central cell megagametophyte leads to development embryo endosperm, respectively. Control cycle progression in is essential for successful development. Central cell-targeted expression D-type cyclin CYCD7;1 (end CYCD7;1) using imprinted FWA promoter overcomes arrest Arabidopsis female gametophyte unfertilized ovule, leading multinucleate cells at high frequency. Unlike FERTILIZATION-INDEPENDENT SEED (fis) mutants, but similar lethal RETINOBLASTOMA-RELATED (rbr) no seed coat triggered. case with loss rbr, post-fertilization end endosperm enhances number nuclei during syncytial induces partial abortion developing seeds, associated enhanced size surviving seeds. The frequency lethality was less than cells, indicating that these aspects are not causally linked. These larger seeds contain embryos composed more wild-type size, surrounded by a cells. Seedlings arising from displayed faster seedling establishment early growth. Similarly, two different embryo-lethal mutants also conferred enlarged siblings, consistent increase being general response sibling lethality, although cellular mechanisms were found be distinct. Our data suggest tight control CYCD activity required optimal formation.