Cell architecture during plant growth and development

BURACHIK, NATALIA; VACS, PAULA; SANTIN, FRANCO; GONZALEZ SCHAIN, NAHUEL; MAZZELLA, AGUSTINA

Rosario

Congreso; XXXIV Reunión de la Sociedad Argentina de Fisiología Vegetal; 2023

Thesize and shape of plant organs are mainly determined by the timing, theduration and the directionality of cell growth; which is coordinated byintegrating endogenous and external signals. Plant developmentin darkness involves rapid hypocotyl growth and theformation of an apical hook, which requires precisecoordination in cellular anisotropic elongation between the convex and concavesides of the hook. Different factors acting as master regulators, includingPIFs (PHYTOCHROME-INTERACTING FACTORS), COP1 (CONSTITUTIVELY PHOTOMORPHOGENIC1),and HYL1 (HYPONASTICLEAVES 1), havea great impact on early development and growth’s decisions in darkness.Cortical microtubules (cMTs),play key roles in determining growth directionality. During cell expansion cMTs aligntransversely to the growth axis, while their longitudinal reorientation hinderscell elongation. Weemploy Arabidopsisseedlings carrying GFP-MAP4 microtubule marker as amodel to investigate the coordination of signals governing differential cellgrowth.