LeProT1, a Transporter for Proline, Glycine Betaine, and γ-Amino Butyric Acid in Tomato Pollen

Schwacke, Rainer; Grallath, Silke; Breitkreuz, Kevin E.; Stransky, Elke; Stransky, Harald; Frommer, Wolf B.; Rentsch, Doris (1999). LeProT1, a Transporter for Proline, Glycine Betaine, and γ-Amino Butyric Acid in Tomato Pollen. The Plant Cell, 11(3), pp. 377-391. American Society of Plant Biologists 10.1105/tpc.11.3.377

Text PlantCell_11_377.pdf - Published Version Restricted to registered users only Available under License Publisher holds Copyright. Download (684kB) | Request a copy

During maturation, pollen undergoes a period of dehydration accompanied by the accumulation of compatible solutes.Solute import across the pollen plasma membrane, which occurs via proteinaceous transporters, is required to support pollen development and also for subsequent germination and pollen tube growth. Analysis of the free amino acid composition of various tissues in tomato revealed that the proline content in flowers was 60 times higher than in any other organ analyzed. Within the floral organs, proline was confined predominantly to pollen, where it represented >70 of total free amino acids. Uptake experiments demonstrated that mature as well as germinated pollen rapidly take up proline. To identify proline transporters in tomato pollen, we isolated genes homologous to Arabidopsis proline transporters. LeProT1 was specifically expressed both in mature and germinating pollen, as demonstrated by RNA in situ hybridization. Expression in a yeast mutant demonstrated that LeProT1 transports proline and γ-amino butyric acid with low affinity and glycine betaine with high affinity. Direct uptake and competition studies demonstrate that LeProT1 constitutes a general transporter for compatible solutes.

Interest & Impact

Downloads

2 since deposited on 13 Jul 2016
0 in the past 12 months

Citations

5 Citations in Web of Science ®
6 Citations in Scopus

Search

in Google Scholar™

Services

Actions (login required)

Edit item

Actions (login required)

Edit item