Transcriptomic analysis reveals the possible roles of sugar metabolism and export for positive mycorrhizal growth responses in soybean
Transcriptomic analysis reveals the possible roles of sugar metabolism and export for positive mycorrhizal growth responses in soybean
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转录组分析揭示了糖代谢和输出对大豆积极菌根生长反应的可能作用
DOI：
10.1111/ppl.12847
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发表时间：
2019
影响因子：
6.4
通讯作者：
Wang Xiurong
中科院分区：
文献类型：
--
作者：
Zhao Shaopeng;Chen A.;Chen Chengjie;Li Chengchen;Xia Rui;Wang Xiurong
为阐明不同大豆品种对丛枝菌根真菌（AM）根际侵染的不同生长反应的分子机制，采用盆栽试验研究了2种大豆基因型和3种AM接种物对AM真菌根际侵染的影响。结果表明，与G.低AM定殖的聚集体（Ga‐L）。根转录组的比较RNA测序分析表明，脂肪酸合成途径显着富集在所有三个AM接种根。然而，糖代谢和运输仅在Ri和Ga-H接种中显著富集，这与这两种接种处理中的正生长响应一致。因此，与Ga-L根相比，Ri和Ga-H根中与糖代谢和运输相关的关键基因的表达水平也上调。其中，两个糖最终将被输出转运体（SWEET）转运基因，GmSWEET 6（Glyma.04G198600）和GmSWEET 15（Glyma.06G166800），以及一个转化酶（Glyma.17G227900）基因仅在Ri和Ga-H根中被诱导。转基因大豆根中的启动子分析进一步证明，GmSWEET 6启动子驱动的GUS在含有丛枝的皮层细胞中高度表达。此外，与Ga-L和非菌根相比，Ri和Ga-H接种增加了茎和根中蔗糖、葡萄糖和果糖的含量。这些结果表明，在植物中的积极的菌根生长反应可能主要是由于具有高定殖能力的AM真菌接种物的光合产物代谢和运输的刺激。
To elucidate molecular mechanisms controlling differential growth responses to root colonization by arbuscular mycorrhizal (AM) fungi varying in colonization and cooperative behavior, a pot experiment was carried out using two soybean genotypes and three AM inocula. The results showed that inoculation by cooperativeRhizophagus irregularis(Ri) or less cooperativeGlomus aggregatumwith high AM colonization (Ga‐H) significantly promoted plant growth compared with inoculation byG. aggregatumwith low AM colonization (Ga‐L). A comparative RNA sequencing analysis of the root transcriptomes showed that fatty acid synthesis pathway was significantly enriched in all three AM inoculation roots. However, sugar metabolism and transport were significantly enriched only in Ri and Ga‐H inoculation, which was consistent with positive growth responses in these two inoculation treatments. Accordingly, the expression levels of the key genes related to sugar metabolism and transport were also upregulated in Ri and Ga‐H roots compared with Ga‐L roots. Of them, two sugars will eventually be exported transporters (SWEET) transporter genes,GmSWEET6(Glyma.04G198600) andGmSWEET15(Glyma.06G166800), and one invertase (Glyma.17G227900) gene were exclusively induced only in Ri and Ga‐H roots. Promoter analyses in transgenic soybean roots further demonstrated thatGUSdriven by theGmSWEET6promoter was highly expressed in arbuscule‐containing cortical cells. Additionally, Ri and Ga‐H inoculation increased the contents of sucrose, glucose and fructose in both shoots and roots compared with those of Ga‐L and non‐mycorrhizal. These results imply that positive mycorrhizal growth responses in plants might mostly be due to the stimulation of photosynthate metabolism and transport by AM fungal inoculum with high colonization capabilities.