title: Pollen Aquaporins: The Solute Factor.
abstract: In the recent years, the biophysical properties and presumed physiological role of aquaporins (AQPs) have been expanded to specialized cells where water and solute exchange are crucial traits. Complex but unique processes such as stomatal movement or pollen hydration and germination have been addressed not only by identifying the specific AQP involved but also by studying how these proteins integrate and coordinate cellular activities and functions. In this review, we referred specifically to pollen-specific AQPs and analyzed what has been assumed in terms of transport properties and what has been found in terms of their physiological role. Unlike that in many other cells, the AQP machinery in mature pollen lacks plasma membrane intrinsic proteins, which are extensively studied for their high water capacity exchange. Instead, a variety of TIPs and NIPs are expressed in pollen. These findings have altered the initial understanding of AQPs and water exchange to consider specific and diverse solutes that might be critical to sustaining pollen's success. The spatial and temporal distribution of the pollen AQPs also reflects a regulatory mechanism that allowing a properly adjusting water and solute exchange.
authors.affiliation: Instituto de Investigaciones en Ingeniería Genética y Biología Molecular - Consejo Nacional de Investigaciones Científicas y Técnicas Buenos Aires, Argentina.
authors.forename: Juliana A
authors.initials: JA
authors.lastname: Pérez Di Giorgio
authors.affiliation: Instituto de Genética Ewald A. Favret - Centro de Investigación en Ciencias Veterinarias y Agronómicas - Instituto Nacional de Tecnología Agropecuaria - Consejo Nacional de Investigaciones Científicas y Técnicas Buenos Aires, Argentina.
authors.forename: Gabriela C
authors.initials: GC
authors.lastname: Soto
authors.affiliation: Instituto de Investigaciones en Ingeniería Genética y Biología Molecular - Consejo Nacional de Investigaciones Científicas y TécnicasBuenos Aires, Argentina; Departamento de Biodiversidad y Biología Experimental, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos AiresBuenos Aires, Argentina.
authors.forename: Jorge P
authors.initials: JP
authors.lastname: Muschietti
authors.affiliation: Departamento de Biodiversidad y Biología Experimental, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos AiresBuenos Aires, Argentina; Instituto de Biodiversidad y Biología Experimental y Aplicada - Universidad de Buenos Aires-Consejo Nacional de Investigaciones Científicas y TécnicasBuenos Aires, Argentina.
authors.forename: Gabriela
authors.initials: G
authors.lastname: Amodeo
keywords: aquaporin; fertilization; membrane intrinsic protein; plant fitness; pollen germination; solute permeability; water and solute transport; water channel