Lack of cytochrome c affects early stages of plant growth and development

ROLDAN FACUNDO; MANSILLA NATANAEL; CANAL MARIA VICTORIA; GRAS DIANA ESTER; WELCHEN ELINA; GONZALEZ DANIEL HECTOR

Mendoza

Congreso; LVIII Congreso Anual SAIB; 2022

Sociedad Argentina de Investigaciones en Bioquímica y Biología Molecular

Cytochrome c (CYT-c) is a soluble heme-protein responsible of the transport of electrons from reduced coenzymes to molecular oxygen in the electron transport chain located in the mitochondria. These are organelles capable of sensing and signaling the cellular energy state, coordinating development through interaction with different growth regulatory pathways. We previously studied the rol of the two genes encoding CYT-c (CYT-c 1 and CYT-c 2) in plant root growth and development. Mutants in CYT-c genes show altered shoot and root growth, with smaller rosettes, lower leaf number, delayed flowering and shorter primary roots. Here we show that these alterations begin in the first steps of plant development, particularly due to leaf primordium and primary root decreased growth rate. In addition, lack of this protein impacts in primary root structure, with a reduced meristematic and elongation zone and shorter mature elongated cells. The root architecture is also modified, with a lower amount of lateral root primordium and differences in lateral root density. Finally, CYTc seems to be involved in the maintenance of a correct auxin response, with a higher DR5 signal in CYTc mutants in both shoot and root tissues, that can be correlated to a possible leaf primordium growth arrestment and higher lateral root densities.