AtTIP1;3 and AtTIP5;1, the only highly expressed Arabidopsis pollen-specific aquaporins, transport water and urea

SOTO GABRIELA; ALLEVA KARINA; MAZZELLA M AGUSTINA; AMODEO GABRIELA; JORGE MUSCHIETTI

FEBS LETTERS

Elsevier Science B.V.

Lugar: Netherlands; Año: 2008 p. 4077 - 4082

0014-5793

Pollination includes processes where water and/or solute movements must be finely regulated, suggesting participatio of aquaporins. Using information available from different transcriptional profilings of Arabidopsis thaliana mature pollen, we showed that the only aquaporins that are selectively and highly expressed in mature pollen are two TIPs: AtTIP1;3 and At-TIP5;1. Pollen exhibited a lower number and more exclusive type of aquaporin expressed genes when compared to other single cell transcriptional profilings. When characterized using Xenopus oocyte swelling assays, AtTIP1;3 and AtTIP5;1 showed intermediate water permeabilities. Although they displayed neither glycerol nor boric acid permeability they both transported urea. In conclusion, these results suggest a function for AtTIP1;3 and AtTIP5;1 as specific water and urea channels in Arabidopsis pollen.