Center for Interdisciplinary Research in Basic Sciences, Jamia Millia Islamia, Jamia Nagar, New Delhi, 110025, India; Department of Molecular & Cellular Engineering, Sam Higginbottom Institute of Agriculture, Technology and Sciences, Allahabad, 211 007, Uttar Pradesh, India.
Department of Chemistry, Rhodes University, Grahamstown 6139, South Africa.
Int J Biol Macromol. 2018 Feb;107(Pt B):2580-2589. doi: 10.1016/j.ijbiomac.2017.10.143. Epub 2017 Oct 24.
Microtubule affinity regulating kinase 4 (MARK4) is a member of AMP-activated protein kinase, found to be involved in apoptosis, inflammation and many other regulatory pathways. Since, its aberrant expression is directly associated with the cell cycle and thus cancer. Therefore, MARK4 is being considered as a potential drug target for cancer therapy. Here, we investigated the mechanism of inhibition of MARK4 activity by citral. Docking studies suggested that citral effectively binds to the active site cavity, and complex is stabilized by several interactions. We further performed molecular dynamics simulation of MARK4-citral complex under explicit water condition for 100ns and observed that binding of citral to MARK4 was quite stable. Fluorescence binding studies suggested that citral strongly binds to MARK4 and thereby inhibits its enzyme activity which was measured by the kinase inhibition assay. We further performed MTT assay and observed that citral inhibits proliferation of breast cancer cell line MCF-7. This work provides a newer insight into the use of citral as novel cancer therapeutics through the MARK4 inhibition. Results may be employed to design novel therapeutic molecule using citral as a scaffold for MARK4 inhibition to fight related diseases.
微管相关蛋白激酶 4（MARK4）是 AMP 激活蛋白激酶家族的一员，其参与细胞凋亡、炎症和许多其他调控途径。由于其异常表达与细胞周期直接相关，因此与癌症有关。因此，MARK4 被认为是癌症治疗的潜在药物靶点。在这里，我们研究了柠檬醛抑制 MARK4 活性的机制。对接研究表明，柠檬醛能有效地结合到活性位点腔中，并通过多种相互作用稳定复合物。我们进一步在明确的水环境下对 MARK4-柠檬醛复合物进行了 100ns 的分子动力学模拟，观察到柠檬醛与 MARK4 的结合非常稳定。荧光结合研究表明，柠檬醛与 MARK4 强烈结合，从而抑制其酶活性，这通过激酶抑制测定来衡量。我们进一步进行了 MTT 测定，观察到柠檬醛抑制乳腺癌细胞系 MCF-7 的增殖。这项工作通过抑制 MARK4 为使用柠檬醛作为新型癌症治疗方法提供了新的见解。研究结果可用于设计使用柠檬醛作为支架抑制 MARK4 的新型治疗分子，以对抗相关疾病。
