Kumar Vinay, Waseem Mohd, Dwivedi Nidhi, Maji Sourobh, Kumar Angad, Thakur Jitendra K
a National Institute of Plant Genome Research; Aruna Asaf Ali Marg ; New Delhi , India.
Plant Signal Behav. 2018 Feb 1;13(2):e1428514. doi: 10.1080/15592324.2018.1428514. Epub 2018 Feb 8.
Med15 is an important subunit of Mediator Tail module and is characterized by a KIX domain present towards amino terminal. In yeast and metazoans, Med15 KIX domain has been found to interact with various transcription factors regulating several processes including carbohydrate metabolism, lipogenesis, stress response and multidrug resistance. Mechanism of Med15 functioning in Arabidopsis is largely unknown. In this study, interactome of KIX domain of Arabidopsis Med15, AtMed15a, was characterized. We found 45 proteins that interact with AtMed15a KIX domain, including 11 transcription factors, 3 single strand nucleic acid-binding proteins and 1 splicing factor. The third helix of the KIX domain was found to be involved in most of the interactions. Mapping of the regions participating in the interactions revealed that the activation domain of a transcription factor, UKTF1 interacted with AtMed15a KIX domain. Thus, our results suggest that in Arabidopsis, activation domain of transcription factors target KIX domain of AtMed15a for their transcriptional responses.
Med15是中介体尾部模块的一个重要亚基，其特征是在氨基末端存在一个KIX结构域。在酵母和后生动物中，已发现Med15 KIX结构域与多种转录因子相互作用，这些转录因子调节包括碳水化合物代谢、脂肪生成、应激反应和多药耐药性在内的多个过程。Med15在拟南芥中的作用机制很大程度上尚不清楚。在本研究中，对拟南芥Med15（AtMed15a）的KIX结构域的相互作用组进行了表征。我们发现有45种蛋白质与AtMed15a KIX结构域相互作用，其中包括11种转录因子、3种单链核酸结合蛋白和1种剪接因子。发现KIX结构域的第三个螺旋参与了大多数相互作用。对参与相互作用区域的定位揭示，转录因子UKTF1的激活结构域与AtMed15a KIX结构域相互作用。因此，我们的结果表明，在拟南芥中，转录因子的激活结构域靶向AtMed15a的KIX结构域以进行转录反应。
