Table_2_Identification of the ALMT gene family in the potato (Solanum tuberosum L.) and analysis of the function of StALMT6/10 in response to aluminum toxicity.docx

IntroductionAluminum (Al)-activated malate transporters (ALMTs) play an important role in the response to Al toxicity, maintenance of ion homeostasis balance, mineral nutrient distribution, and fruit quality development in plants. However, the function of the StALMT gene family in potato remains unknown.
Methods and resultsIn this study, 14 StALMT genes were identified from the potato genome, unevenly distributed on seven different chromosomes. Collinearity and synteny analyses of ALMT genes showed that potatoes had 6 and 22 orthologous gene pairs with Arabidopsis and tomatoes, respectively, and more than one syntenic gene pair was identified for some StALMT gene family members. Real-time quantitative polymerase chain reaction (qPCR) results showed differential expression levels of StALMT gene family members in different tissues of the potato. Interestingly, StALMT1, StALMT6, StALMT8, StALMT10, and StALMT12 had higher expression in the root of the potato cultivar Qingshu No. 9. After being subjected to Al3+ stress for 24 h, the expression of StALMT6 and StALMT10 in roots was evidently increased, displaying their decisive role in Al3+ toxicity.
DiscussionIn addition, overexpression of StALMT6 and StALMT10 in Arabidopsis enhanced its tolerance to Al toxicity. These results indicate that StALMT6 and StALMT10 impart Al3+ resistance in the potato, establishing the foundation for further studies of the biological functions of these genes.

引言
铝（Al）激活的苹果酸转运蛋白（Aluminum-activated malate transporters, ALMTs）在植物应对铝毒、维持离子稳态平衡、矿质养分分配以及果实品质发育中发挥关键作用。然而，马铃薯StALMT基因家族的功能仍未明确。

材料与方法及结果
本研究从马铃薯基因组中鉴定出14个StALMT基因，这些基因不均匀分布于7条不同染色体上。对ALMT基因的共线性与同线性分析表明，马铃薯与拟南芥、番茄分别存在6对和22对直系同源基因对，部分StALMT基因家族成员拥有不止一个同线性基因对。实时荧光定量聚合酶链反应（real-time quantitative polymerase chain reaction, qPCR）结果显示，StALMT基因家族成员在马铃薯不同组织中呈现差异化表达水平。值得注意的是，在马铃薯品种青薯9号的根系中，StALMT1、StALMT6、StALMT8、StALMT10及StALMT12的表达量较高。经Al³+胁迫处理24小时后，根系中StALMT6和StALMT10的表达量显著上调，证实二者在抵御铝毒过程中发挥决定性作用。

讨论
此外，在拟南芥中过表达StALMT6和StALMT10可显著增强其对铝毒的耐受性。上述结果表明，StALMT6和StALMT10可赋予马铃薯铝离子抗性，为后续解析这些基因的生物学功能奠定了重要基础。