Data/hora: 15/06/2024 07:53:03

Biblioteca(s): | Embrapa Milho e Sorgo.
Data corrente: | 03/03/2009
Data da última atualização: | 30/05/2018
Autoria: | LIU, J.; MAGALHAES, J. V.; SHAFF, J.; KOCHIAN, L.
Afiliação: | Jiping Liu, Cornell University; JURANDIR VIEIRA DE MAGALHAES, CNPMS; Jon E. Shaff, Cornell University; Leon V. Kochian, Cornell University.
Título: | Aluminum-activated citrate and malate transporters from the MATE and ALMT families function independently to confer Arabidopsis aluminum tolerance.
Ano de publicação: | 2009
Fonte/Imprenta: | The Plant Journal, Malden, v. 57, n. 3, p. 389-399, 2009.
DOI: | 10.1111/j.1365-313X.2008.03696.x
Idioma: | Inglês
Conteúdo: | 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.
Palavras-Chave: | ALMT; Aluminum tolerance; Aluminum toxicity; Multi-drug; Organic cid exudation; Plasma membrane protein; Toxic compound extrusion; Transporter protein.
Categoria do assunto: | S Ciências Biológicas
Registro original: | Embrapa Milho e Sorgo (CNPMS)
Exemplares: | CNPMS - (21402-1) - UPC - AP - DD -  -  -  - DIS