| RRC ID |
3966
|
| 著者 |
Yuan L, Graff L, Loqué D, Kojima S, Tsuchiya YN, Takahashi H, von Wirén N.
|
| タイトル |
AtAMT1;4, a pollen-specific high-affinity ammonium transporter of the plasma membrane in Arabidopsis.
|
| ジャーナル |
Plant Cell Physiol
|
| Abstract |
Pollen represents an important nitrogen sink in flowers to ensure pollen viability. Since pollen cells are symplasmically isolated during maturation and germination, membrane transporters are required for nitrogen import across the pollen plasma membrane. This study describes the characterization of the ammonium transporter AtAMT1;4, a so far uncharacterized member of the Arabidopsis AMT1 family, which is suggested to be involved in transporting ammonium into pollen. The AtAMT1;4 gene encodes a functional ammonium transporter when heterologously expressed in yeast or when overexpressed in Arabidopsis roots. Concentration-dependent analysis of (15)N-labeled ammonium influx into roots of AtAMT1;4-transformed plants allowed characterization of AtAMT1;4 as a high-affinity transporter with a K(m) of 17 microM. RNA and protein gel blot analysis showed expression of AtAMT1;4 in flowers, and promoter-gene fusions to the green fluorescent protein (GFP) further defined its exclusive expression in pollen grains and pollen tubes. The AtAMT1;4 protein appeared to be localized to the plasma membrane as indicated by protein gel blot analysis of plasma membrane-enriched membrane fractions and by visualization of GFP-tagged AtAMT1;4 protein in pollen grains and pollen tubes. However, no phenotype related to pollen function could be observed in a transposon-tagged line, in which AtAMT1;4 expression is disrupted. These results suggest that AtAMT1;4 mediates ammonium uptake across the plasma membrane of pollen to contribute to nitrogen nutrition of pollen via ammonium uptake or retrieval.
|
| 巻・号 |
50(1)
|
| ページ |
13-25
|
| 公開日 |
2009-1-1
|
| DOI |
10.1093/pcp/pcn186
|
| PII |
pcn186
|
| PMID |
19073648
|
| PMC |
PMC2638712
|
| MeSH |
Arabidopsis / genetics*
Arabidopsis / metabolism
Arabidopsis Proteins / genetics
Arabidopsis Proteins / metabolism*
Cation Transport Proteins / genetics
Cation Transport Proteins / metabolism*
Cell Membrane / metabolism
Cloning, Molecular
DNA, Bacterial / genetics
Gene Expression Regulation, Plant
Genes, Plant
Mutagenesis, Insertional
Plant Proteins / genetics
Plant Proteins / metabolism*
Plants, Genetically Modified / genetics
Plants, Genetically Modified / metabolism
Pollen / genetics*
Pollen / metabolism
Promoter Regions, Genetic
Quaternary Ammonium Compounds / metabolism
RNA, Plant / genetics
|
| IF |
4.062
|
| 引用数 |
56
|
|
WOS 分野
|
PLANT SCIENCES
CELL BIOLOGY
|
| リソース情報 |
| シロイヌナズナ / 植物培養細胞・遺伝子 |
pst00530 |
