Characterization of calcium transporters during the pollen tube growth in Arabidopsis thaliana

BOSSI, JULIAN; MARIANA OBERTELLO; BARBERINI, MARIA LAURA; ESTEVEZ, JOSÉ; MUSCHIETTI, JORGE

Cordoba

Congreso; XXXII Reunión Argentina de Fisiología Vegetal - XVI Congreso Latinoamericano de Fisiología Vegetal; 2018

Sociedad Argentina de Fisiología Vegetal

In plants, calcium signals are involved in multiple physiological processes such as stomatal opening, stress responses, and polarized growth of root hairs and pollen tubes. The signals are given as repetitive oscillations of cytosolic free Ca2+ where the intensity and amplitude correlate according to the stimulus. Pollen tube growth occurs through the concerted action of different factors such as pH, ROS, actin and calcium gradient. Any imbalance between these factors causes aborted pollen tubes and therefore, defects in fertility. In this work, we propose to perform a functional study of the P2B type calcium pumps designated as Autoinhibited Ca2+-ATPases (ACAs) in pollen of Arabidopsis thaliana. These pumps are mainly located in vacuoles, endoplasmic reticulum and plasma membranes and are involved in removing calcium from the cytoplasm. Since some Arabidopsis ACAs are specifically expressed in mature pollen, we propose to explore pollen physiology during reproduction of single and multiple ACA mutant plants. We will analyze how the calcium signature is affected by the use of cytoplasmic and endoplasmic reticulum fluorescent calcium biosensors. These results will provide new perspectives about how pollen tube growth is regulated and it will be also applicable to other cellular polar growth models.