Abstract
The accumulation of compatible solutes such as glycine betaine (betaine) and proline is one of the adaptive strategy for salt and drought stresses. It was indicated that betaine moves dynamically in the plants. However, little is known about the mechanisms of betaine transport in plants. Hitherto, betaine and proline transporters were not reported in the betaine-accumulating plants excluding mangrove. In this research, we isolated HvProT2 gene from betaine-accumulating barley plants.
Under normal and salt stress conditions, HvProT2 was expressed mainly in roots. To investigate the transport activity, the yeast strain carrying mutations in proline, GABA transporters was transformed with HvProT2 in pYES2. The yeast strain expressing HvProT2 showed the uptake of betaine, proline and GABA. These results suggest that HvProT2 has a role of transporting compatible solutes in roots.
To elucidate the physiological role of HvProT2, we are examining the localization of HvProT2 at the cellular and plant levels.
