RALF4/19 ARABIDOPSIS POLLEN PEPTIDES INTERACT WITH POLLEN LRX PROTEINS: AUTOCRINE CONTROL OF POLLEN TUBE GROWTH

JORGE MUSCHIETTI; SOMOZA, SOFÍA C.; MECCHIA, MARTIN; WENGIER, DIEGO; SEDE, ANA ROCIO; BORASSI, CECILIA; ESTEVEZ, JOSE

Córdoba

Conferencia; XXII Reunión Argentina Fisiología Vegetal; 2018

SAFV

RALF4/19 ARABIDOPSIS POLLEN PEPTIDES INTERACT WITH POLLEN LRX PROTEINS: AUTOCRINE CONTROL OF POLLEN TUBE GROWTHJORGE MUSCHIETTI1,2, MARTIN MECCHIA1,3, SOFÍA SOMOZA1, ANA SEDE1, CECILIA BORASSI4, DIEGO WENGIER1, JOSE ESTEVEZ4.1 Instituto de Investigaciones en Ingeniería Genética y Biología Molecular, Dr. Héctor Torres (INGEBI-CONICET), Vuelta de Obligado 2490, C1428ADN Buenos Aires, Argentina. 2 Departamento de Biodiversidad y Biología Experimental, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires. Ciudad Universitaria, Pabellón II, C1428EGA Buenos Aires, Argentina.3 Center for Research in Agricultural Genomics (CRAG), Barcelona, Spain. 4 Fundación Instituto Leloir, IIBBA-CONICET, Buenos Aires, Argentina. Polarized growth involves the expansion of the cell tip, stimulating cell elongation in only one direction. In plants, it takes place in growing pollen tubes, root hairs and cotton fibers. Pollen tube growth is a highly-coordinated process, where actin cytoskeletal arrangement, vesicle mobility, reactive oxygen species (ROS) concentration, regulation of cell wall integrity and calcium (Ca2+) dynamics are involved. Adequate signaling from the external cell wall to the pollen tube cytoplasm is necessary to sustain a proper growth. We have recently reported that two pollen RAPID ALKALINIZATION FACTORs (RALFs), RALF4 and RALF19, act redundantly to regulate the pathway that controls growth and integrity of the pollen tubes (1). Furthermore, we have demonstrated that proteins of the LEUCINE-RICH EXTENSIN (LRX) family, that directly interact with the RALFs, regulate changes in cell wall integrity of pollen tubes (2).Comprehension of how these RALFs and LRXs control pollen tube growth will bring us closer to fully understand the mechanisms governing plant reproduction. The pollen tube is a highly suitable and affordable model to understand how autocrine and paracrine signals take part at different stages during pollination and how pollen tubes transduces that information in order to adapt its growth.(1) RALF4/19 peptides interact with LRX proteins to control pollen tube growth in Arabidopsis. Martin A. Mecchia, Gorka Santos Fernandez, Nadine N. Duss, Sofía C. Somoza, Aurélien Boisson-Dernier, Valeria Gagliardini, Andrea Martínez-Bernardini, Tohnyui Ndinyanka Fabrice, Christoph Ringli, Jorge P. Muschietti* and Ueli Grossniklaus*. Science. 22 Dec 2017: Vol. 358, Issue 6370, pp. 1600-1603. doi: 10.1126/science.aao5467(2) Arabidopsis pollen extensins LRX are required for cell wall integrity during pollen tube growth. Ana R. Sede, Cecilia Borassi, Diego L. Wengier, Martín A. Mecchia, José M. Estevez* and Jorge P. Muschietti*. FEBS Letter. 2018 Jan;592(2):233-243. DOI: 10.1002/1873-3468.12947