Characterization of the Molecular Interaction between Inositol Polyphosphate Multikinase and p62/SQSTM1

Abstract

IPMK is a versatile protein exhibiting catalytic and non-catalytic activities, acting as a signaling hub in the biological pathways. p62, also known as sequestosome-1, is a scaffold protein in signal transduction by interacting with critical signaling intermediates. In this study, I showed that IPMK and p62 physically interact each other. Deficiency of IPMK did not affect autophagy, a cellular degradation system in which p62 known to act as an adaptor. Interestingly, IPMK and p62 in cultured macrophages were dynamically recruited to each other in response to palmitate, which induces TLR4 signaling. Taken together, this study reveals the presence of IPMK-p62 interaction through a direct binding and suggests that this interaction of the two signaling proteins may have a significant role in signal transduction.