Cotton (Gossypium hirsutum), the most important textile crop worldwide, often encounters water stress such as drought or waterlog during its growth season (Summer). To investigate molecular mechanism of water regulation in cotton plants, three cDNAs encoding the plasma membrane intrinsic protein (PIP) were isolated from cotton root cDNA library, and designated GhPIP1;1, GhPIP2;1 and GhPIP2;2, respectively. All of the three PIP proteins displayed water channel activity in Xenopus laevis oocytes. GhPIP2;1 and GhPIP2;2 proteins, however, showed much higher water transport activity than that of th...
