Involvement of the leaf-specific multidrug and toxic compound extrusion (MATE) transporter Nt-JAT2 in vacuolar sequestration of nicotine in Nicotiana tabacum.
Involvement of the leaf-specific multidrug and toxic compound extrusion (MATE) transporter Nt-JAT2 in vacuolar sequestration of nicotine in Nicotiana tabacum.
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DOI：
10.1371/journal.pone.0108789
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发表时间：
2014
期刊：
影响因子：
3.7
通讯作者：
Yazaki K
中科院分区：
文献类型：
--
作者：
Shitan N;Minami S;Morita M;Hayashida M;Ito S;Takanashi K;Omote H;Moriyama Y;Sugiyama A;Goossens A;Moriyasu M;Yazaki K
生物碱在高等植物防御病原体和草食动物中起着关键作用。尼古丁是烟草属植物的主要生物碱，在根组织中生物合成后，通过木质部转运到积累部位，即叶液泡。我们对茉莉酸甲酯处理的烟草BY-2细胞的转录组分析鉴定了几种多药和毒性化合物挤出（MATE）转运蛋白基因。在这项研究中，我们的特点是MATE基因，烟草茉莉酸诱导生物碱转运蛋白2（Nt-JAT 2），它编码的蛋白质，具有32%的氨基酸序列与Nt-JAT 1。Nt-JAT 2 mRNA在整株植物中以非常低的稳态水平表达，但通过茉莉酸甲酯处理以叶特异性方式快速上调。为了表征Nt-JAT 2的功能，在细胞转运测定中使用酵母细胞作为宿主生物体。Nt-JAT 2定位于酵母细胞的质膜上。当在含尼古丁的培养基中孵育时，Nt-JAT 2表达细胞中的尼古丁含量显著低于对照酵母。表达Nt-JAT 2的细胞也显示出较低的其他生物碱含量，如假木贼碱和新烟草碱，但不含黄酮类化合物，这表明Nt-JAT 2转运包括尼古丁在内的各种生物碱。在BY-2细胞中的荧光检测显示Nt-JAT 2-GFP定位于液泡膜。这些发现表明，Nt-JAT 2参与尼古丁从根组织转移后在叶液泡中的尼古丁螯合。
Alkaloids play a key role in higher plant defense against pathogens and herbivores. Following its biosynthesis in root tissues, nicotine, the major alkaloid of Nicotiana species, is translocated via xylem transport toward the accumulation sites, leaf vacuoles. Our transcriptome analysis of methyl jasmonate-treated tobacco BY-2 cells identified several multidrug and toxic compound extrusion (MATE) transporter genes. In this study, we characterized a MATE gene, Nicotiana tabacum jasmonate-inducible alkaloid transporter 2 (Nt-JAT2), which encodes a protein that has 32% amino acid identity with Nt-JAT1. Nt-JAT2 mRNA is expressed at a very low steady state level in whole plants, but is rapidly upregulated by methyl jasmonate treatment in a leaf-specific manner. To characterize the function of Nt-JAT2, yeast cells were used as the host organism in a cellular transport assay. Nt-JAT2 was localized at the plasma membrane in yeast cells. When incubated in nicotine-containing medium, the nicotine content in Nt-JAT2-expressing cells was significantly lower than in control yeast. Nt-JAT2-expressing cells also showed lower content of other alkaloids like anabasine and anatabine, but not of flavonoids, suggesting that Nt-JAT2 transports various alkaloids including nicotine. Fluorescence assays in BY-2 cells showed that Nt-JAT2-GFP was localized to the tonoplast. These findings indicate that Nt-JAT2 is involved in nicotine sequestration in leaf vacuoles following the translocation of nicotine from root tissues.
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影响因子：
4.1
作者：
Lochmann, H;Bazzanella, A;Bächmann, K
通讯作者：
Bächmann, K
嘌呤摄取渗透酶样转运蛋白在植物继发代谢中的作用不断扩大。
影响因子：
5.6
作者：
Jelesko JG
通讯作者：
Jelesko JG
影响因子：
2.3
作者：
BALDWIN, IT
通讯作者：
BALDWIN, IT
影响因子：
7.2
作者：
Kessler, Danny;Bhattacharya, Samik;Baldwin, Ian T.
通讯作者：
Baldwin, Ian T.
影响因子：
12.3
作者：
Krecek P;Skupa P;Libus J;Naramoto S;Tejos R;Friml J;Zazímalová E
通讯作者：
Zazímalová E