Abstract 878: In silico insights from NEK10 modeling, its interactome, and protein-protein interactions
Authors: Eichner Andriele Silva , Pastukhov Igor Semchenkov , Singh Shaneen 
Published: April 2023

Abstract
Cancer is the second-leading cause of death worldwide and by 2040, it is projected that the global burden is expected to grow to 27.5 million new cases. Proteins that directly regulate cell cycle progression are attractive targets in cancer therapy since aberrant regulation of the cell cycle, especially at checkpoints, allows the cells to accumulate DNA errors and continue to grow/divide. A subset of protein kinases functionally involved in regulating the cell cycle and its checkpoints are the eleven members of the human NIMA-related kinases (NEKs). NEK10 is the most divergent member of the NEK family and is linked to melanoma, breast cancer, and various ciliopathies. It is unique in having a centrally positioned coiled-coil flanked catalytic domain, in contrast to the N-terminal catalytic domains of other NEKs. Despite its unique domain architecture and biological relevance, very little is known about its complete structural information and structure-function relationships. To address this gap in knowledge we have modeled and characterized the full-length NEK10 protein, including its unique catalytic domain flanked by two coiled-coil domains, a region with armadillo-type repeats, an ATP binding site, and two unreported putative sites of interaction with ubiquitin (UBA domains). Additionally, we present a comprehensive interactome of NEK10. From this interactome we selected 2 unique and previously unreported NEK10 interactions with the known cancer-causing proteins, Mitogen-activated protein kinase kinase kinase 1 (MAP3K1) and Heat Shock Factor Binding Protein 1 (HSPB1). MAP3K1, a serine/threonine kinase and ubiquitin ligase that plays a pivotal role in integrating cellular responses to mitogenic/metabolic stimuli and mutated in a significant number of cancers, most prominently in luminal breast cancer, contains a protein kinase domain, a PHD finger with E3 ubiquitin ligase activity, and scaffold regions that mediate protein-protein interactions. Our docking analysis shows that I693 of NEK10 located within its kinase domain interacts with well-known phosphosite S275 of MAP3K1. We speculate a scenario in which, upon UV irradiation, NEK10 phosphorylates and activates MAP3K1, which in turn phosphorylates MAP2K1/2-ERK1/2 promoting cell survival. HSPB1, is a molecular chaperone, characterized by a common alpha-crystallin domain in its C-terminus and its overexpression is linked with poor clinical outcome in gastric, uterine, breast, prostate, ovarian, kidney and head/neck cancers. Our docking analysis suggests that the distinctive armadillo repeats of NEK10 may be responsible for its interaction with HSPB1 where H301 of NEK10 forms a salt bridge with I179 of HSPB1, within a known protein-protein hotspot of HSPB1. Our results establish the framework for elucidating the detailed molecular mechanisms of NEK10 interactions with other proteins to further explore its potential as a therapeutic target.
Citation Format: Andriele Silva Eichner, Igor Semchenkov Pastukhov, Shaneen Singh. In silico insights from NEK10 modeling, its interactome, and protein-protein interactions [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 878.