Domain Specific Substrates of Lysine Deacetylase 6

Abstract

Lysine deacetylases (KDACs) are enzymes that regulate the post‐translational modification of lysine by acetate. KDACs serve an important role in numerous biological processes as well as diseases such as asthma, diabetes, and certain cancers. Unlike other metal‐dependent KDACs, KDAC6 contains two catalytic domains. We hypothesize that the catalytic domains of KDAC6 catalyze deacetylation reactions independently, with each domain having several distinct substrates. Several putative substrates have been linked to KDAC6, but which catalytic domain is relevant for deacetylation is generally unclear. We have recombinantly expressed the full‐length KDAC6 as well as the individual catalytic domains. Activity of each construct was measured with peptides derived from the putative substrates, using a combination of a label‐free fluorescence assay and mass spectrometry. Activity was also determined with a selection of full‐length substrate proteins. Differences in activity of the two domains, as well as compared to the full‐length KDAC6, provide insight into the substrate specificity and relative activity of each domain. Computational methods using recently reported crystal structures of the KDAC6 domains and the tested substrates provides additional information about substrate interactions. The identification of independent domain activity and domain specific substrates using these techniques will provide the basis for a greater understanding of the biological roles of KDAC6.Support or Funding InformationThe Louisiana Cancer Research Consortium, National Institutes of Health 5G12MD007595, TL4GM118968, UL1GM118967, and R15GM129682, and National Science Foundation MCB 1817358.This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.