Endocytosis is required during early germination in Arabidopsis thaliana

PAGNUSSAT, LUCIANA ANABELLA, DE LA CANAL, LAURA

Congreso; 46 Annual Meeting Argentine Society for Biochemistry and Molecular Biology; 2010

Sociedad Argentina de Investigación en Bioquímica y Biología Molecular

Endocytosis is required to overcome a variety of cellular functions, including the uptake of extracellular molecules, intercellular signal transduction, and regulation of receptors on the plasma membrane and establishment of cell polarity. During germination, the rapid change from a metabolically resting state to the active condition requires not only the synthesis-a comparative slow process- but the recruitment of several molecules that has been strategically separated from its target localization during seed maturation. We have previously demonstrated that an extracellular lipid transfer protein from sunflower seeds is internalized by endocytosis upon germination. This process probed to be conserved between species, since Arabidopsis seeds also internalized an endocytosis marker during imbibition. In this work we demonstrate the internalization of rhamnogalacturonan-II upon early imbibition in Arabidopsis seeds. To determine the effect of inhibitors of vesicular trafficking in the germination capabilities of Arabidopsis seeds, germinationkinetics were analyzed in the presence of 30 to 50 mM of BFA, Wortmannin, Ly294002 and Tyrphostin A23. The results show that the rate of seed germination is clearly affected when endocytosis is restricted. These findings suggest that recycling of membrane components and&or protein internalization could be important cues during early germination.