Nitrogen affects cluster root formation and expression of putative peptide transporters.
Nitrogen affects cluster root formation and expression of putative peptide transporters.
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氮会影响簇根的形成和推定肽转运蛋白的表达。
DOI：
10.1093/jxb/erp111
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发表时间：
2009
影响因子：
6.9
通讯作者：
Schmidt S
中科院分区：
文献类型：
--
作者：
Paungfoo-Lonhienne C;Schenk PM;Lonhienne TG;Brackin R;Meier S;Rentsch D;Schmidt S
非菌根化的抱子树（Hakea actites）生长在石南荒原中，有机氮（ON）在土壤氮库中占主导地位。Hakea actites使用ON的增长，但集群根在ON收购的作用是未知的。本研究的目的是确定氮形态和浓度如何影响丛生根的形成和肽转运蛋白的表达。水培条件下，低分子量ON>无机N>高分子量ON，而丛根形成的顺序为no-N>ON>无机N。完整的二肽被运输到根和代谢，这表明肽转运蛋白（PTR）的吸收和运输的肽的作用。HaPTR 4是NRT 1/PTR转运蛋白家族的亚组II的成员，其包含植物中最具特征的二肽和三肽转运蛋白，当在酵母中表达时促进二肽和三肽的转运。HaPTR 5和HaPTR 12没有表现出转运活性，这与亚组III中表征不太好的转运蛋白最相似。结果提供了进一步的证据表明，亚组II的NRT 1/PTR家族包含功能性的二肽和三肽转运蛋白。HaPTR 4和HaPTR 12的绿色荧光蛋白融合蛋白分别定位于液泡膜、质膜和内膜，而HaPTR 5定位于身份未知的囊泡。生长在石南地或水培与有限的N供应或饥饿的营养，HaPTR基因的表达最高的簇根和非簇根，和叶片表达增加后，再供应的ON。它的结论是，形成簇根和PTR的表达调节响应于N供应。
Non-mycorrhizal Hakea actites (Proteaceae) grows in heathland where organic nitrogen (ON) dominates the soil nitrogen (N) pool. Hakea actites uses ON for growth, but the role of cluster roots in ON acquisition is unknown. The aim of the present study was to ascertain how N form and concentration affect cluster root formation and expression of peptide transporters. Hydroponically grown plants produced most biomass with low molecular weight ON>inorganic N>high molecular weight ON, while cluster roots were formed in the order no-N>ON>inorganic N. Intact dipeptide was transported into roots and metabolized, suggesting a role for the peptide transporter (PTR) for uptake and transport of peptides. HaPTR4, a member of subgroup II of the NRT1/PTR transporter family, which contains most characterized di- and tripeptide transporters in plants, facilitated transport of di- and tripeptides when expressed in yeast. No transport activity was demonstrated for HaPTR5 and HaPTR12, most similar to less well characterized transporters in subgroup III. The results provide further evidence that subgroup II of the NRT1/PTR family contains functional di- and tripeptide transporters. Green fluorescent protein fusion proteins of HaPTR4 and HaPTR12 localized to tonoplast, and plasma- and endomembranes, respectively, while HaPTR5 localized to vesicles of unknown identity. Grown in heathland or hydroponic culture with limiting N supply or starved of nutrients, HaPTR genes had the highest expression in cluster roots and non-cluster roots, and leaf expression increased upon re-supply of ON. It is concluded that formation of cluster roots and expression of PTR are regulated in response to N supply.
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影响因子：
1.1
作者：
MOORE, CWE;KERAITIS, K
通讯作者：
KERAITIS, K
影响因子：
4
作者：
Campalans, A;Pagès, M;Messeguer, R
通讯作者：
Messeguer, R
影响因子：
7.2
作者：
Dietrich, D;Hammes, U;Rentsch, D
通讯作者：
Rentsch, D
影响因子：
7.4
作者：
Komarova, Nataliya Y.;Thor, Kathrin;Rentsch, Doris
通讯作者：
Rentsch, Doris
影响因子：
9.4
作者：
Benjdia, M;Rikirsch, E;Wipf, D
通讯作者：
Wipf, D