In eukaryotes, phosphorylation of the α-subunit of eIF2 is a mechanism to adjust cellular gene expression profiles in response to specific signals. The eIF2α kinases are a group of serine-threonine kinases that perform important functions in response to infection, proteotoxicity, and nutrient scavenging. The conserved nature of eIF2α kinases among fungi makes them potential evolutionary markers, which may contribute to deeper understanding of taxonomy and evolution. To date, only few studies are available of eIF2α kinases in black yeasts, which are members of Chaetothyriales containing potential agents of a gamut of major human diseases, such as chromoblastomycosis, phaeohyphomycosis and mycetoma. To establish the phylogenetic validity of sequences of eIF2α kinases hypothetical genes, we compared these genes between members of different classes of fungi, including black yeasts and allies, aiming at evaluation of the phylogeny of this group using an alternative molecular marker, compared to standard ribosomal genes. Trees generated with eIF2α kinase sequences of fungi were compared with those generated by ribosomal internal transcribed spacers (ITS rDNA) sequences from the same species. Sequences used were obtained from the protein Non-redundant database of NCBI, were aligned using CLUSTALX v1.8 and alignments were analyzed with RAxML v8.2.9 on the CIPRES Science Gateway portal. The trees generated had similar topologies, demonstrating that eIF2α kinases hypothetical gene sequences present a coherent reflection of evolution among fungi, compared to trees reconstructed by the use of ribosomal sequences. Our preliminary findings with a limited dataset strongly suggest that the evolution of kinases among black yeasts follows a similar path as revealed by ribosomal data, which underlines the validity of current taxonomy of black yeasts and relatives.

中文翻译：

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具有假设 EIF2AK2 激酶基因的黑色酵母样真菌（毛壳菌属）系统发育重建的新分子标记

在真核生物中，eIF2 α-亚基的磷酸化是一种响应特定信号调整细胞基因表达谱的机制。eIF2α 激酶是一组丝氨酸-苏氨酸激酶，在响应感染、蛋白毒性和营养清除方面发挥重要作用。eIF2α 激酶在真菌中的保守性质使其成为潜在的进化标记，这可能有助于更深入地了解分类学和进化。迄今为止，只有少数关于黑色酵母中 eIF2α 激酶的研究可用，黑色酵母是毛壳孢菌的成员，含有一系列主要人类疾病的潜在病原体，如染色芽生菌病、褐丝菌病和足菌肿。为了确定 eIF2α 激酶假设基因序列的系统发育有效性，我们比较了不同类别真菌成员之间的这些基因，包括黑酵母和盟友，旨在使用替代分子标记评估该组的系统发育，与标准核糖体基因相比。用真菌的 eIF2α 激酶序列生成的树与来自同一物种的核糖体内部转录间隔 (ITS rDNA) 序列生成的树进行了比较。使用的序列来自 NCBI 的蛋白质非冗余数据库，使用 CLUSTALX v1.8 进行比对，并在 CIPRES Science Gateway 门户上使用 RAxML v8.2.9 分析比对。生成的树具有相似的拓扑结构，表明与使用核糖体序列重建的树相比，eIF2α 激酶假设基因序列呈现出真菌进化的连贯反映。