Identification of aquaporins in Fragaria x ananassa and analysis of their expression pattern during fruit ripening.

CLAUDIA BUSTAMANTE; PAULA MUT; KARINA ALLEVA; MOIRA SUTKA; GUSTAVO MARTINEZ; MARCOS CIVELLO; GABRIELA AMODEO

Pinamar, Buenos Aires, Argentina

Congreso; 10th Congress of the Panamercian Association for Biochemistry and Molecular Biology and 41th SAIB Annual Meeting and 20th SAN Annual Meeting; 2005

SAIB

In strawberry, fruit develops and ripens rapidly, forcing a brief commercial life. Although fruit softening is partially due to cell wall degradation, and a growing number of enzymes related to this process have been characterized, the contribution of fruit turgor and water movement pathways should not be neglected. We therefore focused our work in the identification of water channels in order to characterize their expression and putative contribution to strawberry fruit ripening. A cDNA library from ripe strawberry fruit (cv Chandler) allowed us isolating a 1.2 Kb fragment (FaMIP). The phylogenetic analysis of the full length deduced amino acid sequence confirms that FaMIP has high homology with plasma membrane aquaporins, more specifically PIP1 subgroup. Northern-blot analysis revealed that FaMIP expresses specifically in fruit tissue and that its expression increases through strawberry fruit ripening. Moreover, the expression is repressed by auxins. We conclude that water channels are present in strawberry fruit and modify their expression pattern during fruit ripening.