AtTIP1;3 and AtTIP5;1, the only highly expressed Arabidopsis pollen-specific aquaporins, transport water and urea Soto G., Alleva K., Mazzella MA., Amodeo G. and Muschietti J.

SOTO, GABRIELA; ALLEVA, KARINA; MAZZELLA, MARIA AGUSTINA; AMODEO, GABRIELA; MUSCHIETTI, JORGE

FEBS LETTERS

ELSEVIER SCIENCE BV

Año: 2008 vol. 582 p. 4077 - 4082

0014-5793

Pollination includes processes where water and/or solutemovements must be finely regulated, suggesting participationof aquaporins. Using information available from different transcriptionalprofilings of Arabidopsis thaliana mature pollen, weshowed that the only aquaporins that are selectively and highlyexpressed in mature pollen are two TIPs: AtTIP1;3 andAtTIP5;1. Pollen exhibited a lower number and more exclusivetype of aquaporin expressed genes when compared to other singlecell transcriptional profilings. When characterized using Xenopusoocyte swelling assays, AtTIP1;3 and AtTIP5;1 showedintermediate water permeabilities. Although they displayed neitherglycerol nor boric acid permeability they both transportedurea. In conclusion, these results suggest a function for AtTIP1;3and AtTIP5;1 as specific water and urea channels in Arabidopsispollen.