共 37 条
Aluminum-activated citrate and malate transporters from the MATE and ALMT families function independently to confer Arabidopsis aluminum tolerance
被引:400
作者:
Liu, Jiping
[1
]
Magalhaes, Jurandir V.
[2
]
Shaff, Jon
[1
]
Kochian, Leon V.
[1
]
机构:
[1] Cornell Univ, USDA ARS, US Plant Soil & Nutr Lab, Ithaca, NY 14853 USA
[2] Embrapa Maize & Sorghum, BR-35701970 Sete Lagoas, Matto Grosso, Brazil
基金:
美国农业部;
关键词:
aluminum toxicity;
aluminum tolerance;
ALMT;
multi-drug and toxic compound extrusion;
transporter protein;
plasma membrane protein;
organic acid exudation;
TRITICUM-AESTIVUM L;
ACID;
GENE;
MULTIDRUG;
EFFLUX;
RESISTANCE;
MECHANISM;
MEMBER;
RICE;
EXUDATION;
D O I:
10.1111/j.1365-313X.2008.03696.x
中图分类号:
Q94 [植物学];
学科分类号:
071001 ;
摘要:
Aluminum-activated root malate and citrate exudation play an important role in plant Al tolerance. This paper characterizes AtMATE, a homolog of the recently discovered sorghum and barley Al-tolerance genes, shown here to encode an Al-activated citrate transporter in Arabidopsis. Together with the previously characterized Al-activated malate transporter, AtALMT1, this discovery allowed us to examine the relationship in the same species between members of the two gene families for which Al-tolerance genes have been identified. AtMATE is expressed primarily in roots and is induced by Al. An AtMATE T-DNA knockdown line exhibited very low AtMATE expression and Al-activated root citrate exudation was abolished. The AtALMT1 AtMATE double mutant lacked both Al-activated root malate and citrate exudation and showed greater Al sensitivity than the AtALMT1 mutant. Therefore, although AtALMT1 is a major contributor to Arabidopsis Al tolerance, AtMATE also makes a significant but smaller contribution. The expression patterns of AtALMT1 and AtMATE and the profiles of Al-activated root citrate and malate exudation are not affected by the presence or absence of the other gene. These results suggest that AtALMT1-mediated malate exudation and AtMATE-mediated citrate exudation evolved independently to confer Al tolerance in Arabidopsis. However, a link between regulation of expression of the two transporters in response to Al was identified through work on STOP1, a transcription factor that was previously shown to be necessary for AtALMT1 expression. Here we show that STOP1 is also required for AtMATE expression and Al-activated citrate exudation.
引用
收藏
页码:389 / 399
页数:11
相关论文