title: Biophysical changes of ATP binding pocket may explain loss of kinase activity in mutant DAPK3 in cancer: A molecular dynamic simulation analysis.
abstract: DAPK3 belongs to family of DAPK (death-associated protein kinases) and is involved in the regulation of progression of the cell cycle, cell proliferation, apoptosis and autophagy. It is considered as a tumor suppressor kinase, suggesting the loss of its function in case of certain specific mutations. The T112M, D161N and P216S mutations in DAPK3 have been observed in cancer patients. These DAPK3 mutants have been associated with very low kinase activity, which results in the cellular progression towards cancer. However, a clear understanding of the structural and biophysical variations that occur in DAPK3 with these mutations, resulting in the decreased kinase activity has yet not been deciphered. We performed a molecular dynamic simulation study to investigate such structural variations. Our results revealed that mutations caused a significant structural variation in DAPK3, majorly concentrated in the flexible loops that form part of the ATP binding pocket. Interestingly, D161N and P216S mutations collapsed the ATP binding pocket through flexible loops invasion, hindering ATP binding which resulted in very low kinase activity. On the contrary, T112M mutant DAPK3 reduces ATP binding potential through outward distortion of flexible loops. In addition, the mutant lacked characteristic features of the active protein kinase including proper interaction between HR/FD and DFG motifs, well structured hydrophobic spine and Lys42-Glu64 salt bridge interaction. These observations could possibly explain the underlying mechanism associated with the loss of kinase activity with T112M, D161N and P216S mutation in DAPK3.
authors.affiliation: Department of Biotechnology, Indian Institute of Technology, Kharagpur, West Bengal, Pin: 721302, India. Electronic address: tarun3agarwal5@gmail.com.
authors.forename: Tarun
authors.initials: T
authors.lastname: Agarwal
authors.affiliation: Advanced Medical and Dental Institute, Universiti Sains Malaysia, 13200 Bertam, Pulau Pinang, Malaysia. Electronic address: nithyanny90@hotmail.com.
authors.forename: Nithyanan
authors.initials: N
authors.lastname: Annamalai
authors.affiliation: Department of Biotechnology, Indian Institute of Technology, Kharagpur, West Bengal, Pin: 721302, India. Electronic address: tkmaiti@hijli.iitkgp.ernet.in.
authors.forename: Tapas Kumar
authors.initials: TK
authors.lastname: Maiti
authors.affiliation: Advanced Medical and Dental Institute, Universiti Sains Malaysia, 13200 Bertam, Pulau Pinang, Malaysia. Electronic address: hasni@amdi.usm.edu.my.
authors.forename: Hasni
authors.initials: H
authors.lastname: Arsad
mesh_terms: D000255:Adenosine Triphosphate / Q000378:metabolism*; D017209:Apoptosis / Q000235:genetics; D001343:Autophagy / Q000235:genetics; D001665:Binding Sites / Q000502:physiology*; D002453:Cell Cycle / Q000235:genetics; D049109:Cell Proliferation / Q000235:genetics; D018360:Crystallography, X-Ray; D064550:Death-Associated Protein Kinases / Q000235:genetics* / Q000648:ultrastructure; D006801:Humans; D008958:Models, Molecular; D056004:Molecular Dynamics Simulation; D009154:Mutation; D009369:Neoplasms / Q000235:genetics*; D010766:Phosphorylation; D017434:Protein Structure, Tertiary
chemical_list: D000255:Adenosine Triphosphate; C579101:DAPK3 protein, human; D064550:Death-Associated Protein Kinases
keywords: ATP binding site; Apoptosis; Autophagy; Death associated protein kinase 3 (DAPK3); Molecular dynamic simulation