| RRC ID |
3781
|
| 著者 |
Shimoda Y, Shimoda-Sasakura F, Kucho K, Kanamori N, Nagata M, Suzuki A, Abe M, Higashi S, Uchiumi T.
|
| タイトル |
Overexpression of class 1 plant hemoglobin genes enhances symbiotic nitrogen fixation activity between Mesorhizobium loti and Lotus japonicus.
|
| ジャーナル |
Plant J
|
| Abstract |
Plant hemoglobins (Hbs) have been divided into three groups: class 1, class 2, and truncated Hbs. The various physiological functions of class 1 Hb include its role as a modulator of nitric oxide (NO) levels in plants. To gain more insight into the functions of class 1 Hbs, we investigated the physical properties of LjHb1 and AfHb1, class 1 Hbs of a model legume Lotus japonicus and an actinorhizal plant Alnus firma, respectively. Spectrophotometric analysis showed that the recombinant form of the LjHb1 and AfHb1 proteins reacted with NO. The localization of LjHb1 expression was correlated with the site of NO production. Overexpression of LjHb1 and AfHb1 by transformed hairy roots caused changes in symbiosis with rhizobia. The number of nodules formed on hairy roots overexpressing LjHb1 or AfHb1 increased compared with that on untransformed hairy roots. Furthermore, nitrogenase activity as acetylene-reduction activity (ARA) of LjHb1- or AfHb1-overexpressing nodules was higher than that of the vector control nodules. Microscopic observation with a NO-specific fluorescent dye suggested that the NO level in LjHb1- and AfHb1-overexpressing nodules was lower than that of control nodules. Exogenous application of a NO scavenger enhanced ARA in L. japonicus nodules, whereas a NO donor inhibited ARA. These results suggest that the basal level of NO in nodules inhibits nitrogen fixation, and overexpression of class 1 Hbs enhances symbiotic nitrogen fixation activity by removing NO as an inhibitor of nitrogenase.
|
| 巻・号 |
57(2)
|
| ページ |
254-63
|
| 公開日 |
2009-1-1
|
| DOI |
10.1111/j.1365-313X.2008.03689.x
|
| PII |
TPJ3689
|
| PMID |
18801013
|
| MeSH |
Acetylene / metabolism
Alnus / genetics
Alnus / metabolism
Alnus / microbiology
Alphaproteobacteria / metabolism*
Gene Expression Regulation, Plant
Genes, Plant
Hemoglobins / genetics
Hemoglobins / metabolism*
Lotus / genetics*
Lotus / metabolism
Lotus / microbiology
Nitric Oxide / metabolism
Nitrogen Fixation / genetics*
Plant Proteins / genetics
Plant Proteins / metabolism
Plants, Genetically Modified / genetics
Plants, Genetically Modified / metabolism
Plants, Genetically Modified / microbiology
RNA, Plant / genetics
Recombinant Proteins / genetics
Recombinant Proteins / metabolism
Root Nodules, Plant / genetics
Root Nodules, Plant / metabolism
Root Nodules, Plant / microbiology
Symbiosis
|
| IF |
6.141
|
| 引用数 |
72
|
|
WOS 分野
|
PLANT SCIENCES
|
| リソース情報 |
| ミヤコグサ・ダイズ |
Miyakojima MG20 |
