Transport functions and expression analysis of vacuolar membrane aquaporins in response to various stresses in rice.
The vacuole, a multifunctional organelle of most plant cells, has very important roles in space filling, osmotic adjustment, storage and digestion. Previous researches suggested that aquaporins in the tonoplast were involved in vacuolar functions. The rice genome contains 33 aquaporin genes, 10 of which encode tonoplast intrinsic proteins (TIPs). However, the function of each individual TIP isoform and the integrated function of TIPs under various physiological conditions remain elusive. Here, five rice TIP members were characterized with water and/or glycerol transport activities using the Xenopus oocyte expression system. OsTIP1;2, OsTIP2;2, OsTIP4;1 and OsTIP5;1 possessed water transport activity. OsTIP1;2, OsTIP3;2 and OsTIP4;1 were demonstrated with glycerol transport activity. Rice TIP expression patterns under various abiotic stress conditions including dehydration, high salinity, abscisic acid (ABA) and during seed germination were investigated by real-time PCR. OsTIP1s (OsTIP1;1 and OsTIP1;2) were highly expressed during seed germination, whereas OsTIP3s (OsTIP3;1 and OsTIP3;2) were specifically expressed in mature seeds with a decrease in expression levels upon germination. The results of this research provided a functional and expression profiles of rice TIPs.
Li
Guo-Wei
GW
Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, and Graduate School of the Chinese Academy of Sciences, 300 Fenglin Road, Shanghai 200032, China.
Peng
Yan-Hui
YH
Yu
Xin
X
Zhang
Min-Hua
MH
Cai
Wei-Ming
WM
Sun
Wei-Ning
WN
Su
Wei-Ai
WA
D000040:Abscisic Acid / Q000494:pharmacology; D000818:Animals; D020346:Aquaporins / Q000235:genetics* / Q000378:metabolism; D001692:Biological Transport / Q000187:drug effects; D003681:Dehydration; D020869:Gene Expression Profiling; D018506:Gene Expression Regulation, Plant / Q000187:drug effects; D018525:Germination / Q000187:drug effects / Q000235:genetics; D005990:Glycerol / Q000378:metabolism; D007425:Intracellular Membranes / Q000187:drug effects / Q000378:metabolism*; D008565:Membrane Proteins / Q000235:genetics / Q000378:metabolism; D009865:Oocytes / Q000187:drug effects / Q000378:metabolism; D012275:Oryza / Q000187:drug effects / Q000235:genetics*; D010940:Plant Proteins / Q000235:genetics / Q000378:metabolism; D018517:Plant Roots / Q000187:drug effects / Q000235:genetics; D018520:Plant Shoots / Q000187:drug effects / Q000235:genetics; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D054712:Salinity; D036226:Seedlings / Q000187:drug effects / Q000235:genetics; D012639:Seeds / Q000187:drug effects / Q000235:genetics; D013312:Stress, Physiological / Q000187:drug effects / Q000235:genetics*; D014617:Vacuoles / Q000187:drug effects / Q000378:metabolism*; D014867:Water / Q000378:metabolism; D014981:Xenopus
D020346:Aquaporins; D008565:Membrane Proteins; D010940:Plant Proteins; D012333:RNA, Messenger; C077491:tonoplast intrinsic protein, plant; D014867:Water; D000040:Abscisic Acid; D005990:Glycerol