Morphogenetic determinants of plant female germ cell precursors specification andplasticity

INES, OUEDRAOGO; MOSCA, GABRIELA; DELGADO LUCIANA; OLIVIER LEBLANC; HERNANDEZ-LAGANA, ELVIRA; MENDOCILLA SATO; HAMANT O.; BOUDAOUD, A.; GODIN, C. ; GROSSNIKLAUS, U. ; LARTAUD, M. ; CONÉJÉRO, G. ; BAROUX, C. ; AUTRAN, D.APHNÉ

Rosario

Congreso; IV International Congress on Apomixis Research; 2023

In higher plants, female gametes formation is a crucial step in the plant reproductive cycle and determinesseed formation, hence participating in crop yields. The plant female germline initiates in the ovule primordium,with the specification of the Megaspore Mother Cell (MMC), the only cell which will undergo meiosis toproduce gametes. However, germ cell fate in the early ovule appears flexible. Genetic variants and apomicticspecies show that somatic cells neighboring the MMC can enter the MMC identity program or even directlyproduce female gametophytes without meiosis. By combining 3D morphometrics, growth modelling, genemarkers and genetic analyses, we have shown in Arabidopsis that this developmental plasticity is also part ofMMC ontology in wild-type, before channeling toward MMC singleness, a process controlled by ovule tissuegrowth. Recently, we developed new routes further exploring Arabidopsis MMC growth using time-lapse (3D+t),and establishing a 3D morphometric atlas of ovule primordia in Maize, a sexual grass model, to understand thegenericity of MMC formation and its plasticity.