Skip to main content
. 2018 Jun 20;7:F1000 Faculty Rev-804. [Version 1] doi: 10.12688/f1000research.14508.1

Figure 2. Model for acquisition of cell identity in the female gametophyte.

Figure 2.

RKD genes (expression pattern shown in blue) may act early to set up a default egg cell state in the gametophyte and continue to promote egg cell identity later. At the micropylar pole, auxin signaling, together with sporophytically active AMP1 (green) which could potentially affect the auxin:cytokinin balance, acts to specify synergid cell identity. The egg cell (with blue nucleus) maintains synergid identity by suppressing egg cell fate in the adjacent synergid cells (black nuclei). CKI1 (orange) represses micropylar fates in the chalazal domain and is needed to specify central cell identity (polar nuclei in red) in a pathway involving AHP proteins. CKI1, together with additional factors that may be provided from the chalaza, specifies antipodal cell fates (yellow nuclei). Note: The nuclei in this sketch are not drawn to scale. AC, antipodal cell; AHP, Arabidopsis phosphotransfer protein; AMP1, altered meristem program 1; CC, central cell; CK, cytokinin; CKI1, CYTOKININ INSENSITIVE 1; EC, egg cell; RKD, RWP-RK DOMAIN CONTAINING; SC, synergid cell.