Background

Potato (Solanum tuberosum L.), the third most important non-cereal crop, is sensitive to high temperature. Histone modifications have been known to regulate various abiotic stress responses. However, the role of histone methyltransferases and demethylases remain unexplored in potato under heat stress.

Methods

Potato genome database was used for genome-wide analysis of StPRMT and StHDMA gene families, which were further characterized by analyzing gene structure, conserved motif, domain organization, sub-cellular localization, promoter region and phylogenetic relationships. Additionally, expression profiling under high-temperature stress in leaf and stolon tissue of heat contrasting potato genotypes was done to study their role in response to high temperature stress.

Results

The genome-wide analysis led to identification of nine StPRMT and eleven StHDMA genes. Structural analysis, including conserved motifs, exon/intron structure and phylogenetic relationships classified StPRMT and StHDMA gene families into two classes viz. Class I and Class II. A variety of cis-regulatory elements were explored in the promoter region associated with light, developmental, hormonal and stress responses. Prediction of sub-cellular localization of StPRMT proteins revealed their occurrence in nucleus and cytoplasm, whereas StHDMA proteins were observed in different sub-cellular compartments. Furthermore, expression profiling of StPRMT and StHDMA gene family members revealed genes responding to heat stress. Heat-inducible expression of StPRMT1, StPRMT3, StPRMT4 and StPRMT5 in leaf and stolon tissues of HS and HT cultivar indicated them as probable candidates for enhancing thermotolerance in potato. However, StHDMAs responded dynamically in leaf and stolon tissue of heat contrasting genotypes under high temperature.

Conclusion

The current study presents a detailed analysis of histone modifiers in potato and indicates their role as an important epigenetic regulators modulating heat tolerance.

General significance

Understanding epigenetic mechanisms underlying heat tolerance in potato will contribute towards breeding of thermotolerant potato varieties.

中文翻译：

---

全基因组鉴定和表达分析揭示了组蛋白甲基转移酶和去甲基化酶基因在马铃薯热应激反应中的作用（Solanum tuberosum L.）

背景

马铃薯（Solanum tuberosum L.）是第三重要的非谷类作物，对高温敏感。已知组蛋白修饰可调节各种非生物应激反应。然而，组蛋白甲基转移酶和去甲基酶在热应激下马铃薯中的作用仍未被探索。

方法

利用马铃薯基因组数据库对StPRMT和StHDMA基因家族进行全基因组分析，通过分析基因结构、保守基序、结构域组织、亚细胞定位、启动子区域和系统发育关系进一步表征。此外，对热对比马铃薯基因型的叶片和匍匐茎组织在高温胁迫下的表达谱进行了研究，以研究它们在响应高温胁迫中的作用。

结果

全基因组分析鉴定出 9 个StPRMT和 11 个StHDMA基因。结构分析，包括保守基序、外显子/内含子结构和系统发育关系，将StPRMT和StHDMA基因家族分为两类，即。I 类和 II 类。在与光、发育、激素和应激反应相关的启动子区域中探索了多种顺式调节元件。StPRMT 蛋白的亚细胞定位预测揭示了它们出现在细胞核和细胞质中，而 StHDMA 蛋白则在不同的亚细胞区室中观察到。此外，StPRMT和StHDMA基因家族成员的表达谱揭示了响应热应激的基因。StPRMT1、StPRMT3、StPRMT4和StPRMT5在HS和HT品种的叶和匍匐茎组织中的热诱导表达表明它们可能是增强马铃薯耐热性的候选者。然而，在高温下，StHDMAs在热对比基因型的叶和匍匐茎组织中动态响应。

结论

目前的研究对马铃薯中的组蛋白修饰剂进行了详细分析，并表明它们作为调节耐热性的重要表观遗传调节剂的作用。

一般意义

了解马铃薯耐热性的表观遗传机制将有助于培育耐热马铃薯品种。