RRC ID |
53148
|
著者 |
Tokizawa M, Kobayashi Y, Saito T, Kobayashi M, Iuchi S, Nomoto M, Tada Y, Yamamoto YY, Koyama H.
|
タイトル |
SENSITIVE TO PROTON RHIZOTOXICITY1, CALMODULIN BINDING TRANSCRIPTION ACTIVATOR2, and other transcription factors are involved in ALUMINUM-ACTIVATED MALATE TRANSPORTER1 expression.
|
ジャーナル |
Plant Physiol
|
Abstract |
In Arabidopsis (Arabidopsis thaliana) the root apex is protected from aluminum (Al) rhizotoxicity by excretion of malate, an Al chelator, by ALUMINUM-ACTIVATED MALATE TRANSPORTER1 (AtALMT1). AtALMT1 expression is fundamentally regulated by the SENSITIVE TO PROTON RHIZOTOXICITY1 (STOP1) zinc finger protein, but other transcription factors have roles that enable Al-inducible expression with a broad dynamic range. In this study, we characterized multiple cis-elements in the AtALMT1 promoter that interact with transcription factors. In planta complementation assays of AtALMT1 driven by 5' truncated promoters of different lengths showed that the promoter region between -540 and 0 (the first ATG) restored the Al-sensitive phenotype of atalm1 and thus contains cis-elements essential for AtALMT1 expression for Al tolerance. Computation of overrepresented octamers showed that eight regions in this promoter region contained potential cis-elements involved in Al induction and STOP1 regulation. Mutation in a position around -297 from the first ATG completely inactivated AtALMT1 expression and Al response. In vitro binding assays showed that this region contained the STOP1 binding site, which accounted for the recognition by four zinc finger domains of the protein. Other positions were characterized as cis-elements that regulated expression by repressors and activators and a transcription factor that determines root tip expression of AtALMT1. From the consensus of known cis-elements, we identified CALMODULIN-BINDING TRANSCRIPTION ACTIVATOR2 to be an activator of AtALMT1 expression. Al-inducible expression of AtALMT1 changed transcription starting sites, which increased the abundance of transcripts with a shortened 5' untranslated region. The present analyses identified multiple mechanisms that regulate AtALMT1 expression.
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巻・号 |
167(3)
|
ページ |
991-1003
|
公開日 |
2015-3-1
|
DOI |
10.1104/pp.114.256552
|
PII |
pp.114.256552
|
PMID |
25627216
|
PMC |
PMC4348791
|
MeSH |
Adaptation, Physiological / drug effects
Aluminum / toxicity
Arabidopsis / drug effects
Arabidopsis / genetics*
Arabidopsis / metabolism
Arabidopsis Proteins / chemistry
Arabidopsis Proteins / genetics
Arabidopsis Proteins / metabolism*
Base Sequence
Gene Expression Profiling
Gene Expression Regulation, Plant / drug effects
Genetic Complementation Test
Glucuronidase / metabolism
Models, Biological
Molecular Sequence Data
Mutation / genetics
Organic Anion Transporters / genetics
Organic Anion Transporters / metabolism*
Plants, Genetically Modified
Promoter Regions, Genetic
Protein Binding / drug effects
Protein Structure, Tertiary
RNA, Messenger / genetics
RNA, Messenger / metabolism
Staining and Labeling
Transcription Factors / chemistry
Transcription Factors / genetics
Transcription Factors / metabolism*
Transcription Initiation Site
Transcription, Genetic / drug effects
Zinc Fingers
|
IF |
6.902
|
引用数 |
57
|
リソース情報 |
シロイヌナズナ / 植物培養細胞・遺伝子 |
sja05800 |