Mutational analysis of two residues in the DYRK homology box of the protein kinase DYRK1A

Abstract

ObjectiveDual specificity tyrosine phosphorylation-regulated kinases (DYRK) contain a characteristic sequence motif (DYRK homology box, DH box) that is located N-terminal of the catalytic domain and supports the autophosphorylation of a conserved tyrosine during maturation of the catalytic domain. Two missense mutations in the DH box of human DYRK1B were recently identified as causative of a rare familiar form of metabolic syndrome. We have recently shown that these amino acid exchanges impair maturation of the kinase domain. Here we report the characterization of DYRK1A point mutants (D138P, K150C) that correspond to the pathogenic DYRK1B variants (H90P, R102C).ResultsWhen expressed in HeLa cells, DYRK1A-D138P and K150C showed no significant difference from wild type DYRK1A regarding the activating tyrosine autophosphorylation or catalytic activity towards exogenous substrates. However, both DYRK1A variants were underphosphorylated on tyrosine when expressed in a bacterial cell free in vitro translation system. These results suggest that D138 and K150 participate in the maturation of the catalytic domain of DYRK1A albeit the mutation of these residues is compensated under physiological conditions.Electronic supplementary materialThe online version of this article (10.1186/s13104-018-3416-4) contains supplementary material, which is available to authorized users.

Dual-Specificity, Tyrosine Phosphorylation-Regulated Kinases (DYRKs) and cdc2-Like Kinases (CLKs) in Human Disease, an Overview

“…Alignment of DYRKs and CLKs sequences shows the classical central kinase catalytic domain flanked by N-terminal and C-terminal extensions ( Figure 3 and Figure 4 ). The N-terminal domain of all DYRKs displays a conserved DYRK homology box (DH) [ 16 ] that contributes to autophosphorylation of a conserved tyrosine in the kinase domain (Tyr321 in DYRK1A) during maturation of the kinase [ 17 , 18 ]. Autophosphorylation on the tyrosine residue is preceded by hydroxylation of a proline residue by the PHD1 prolyl hydroxylase, an absolute requirement for catalytic activation of the kinase [ 19 ].…”

Functions ofSRPK,CLKandDYRKkinases in stem cells, development, and human developmental disorders

“…For example, the NAPA domain is not present in Class I DYRK1A‐B but is essential for catalytic activation in Class II DYRK2‐4 [ 62 ]. The DH box plays a minor role in DYRK maturation and auto‐phosphorylation alongside the NAPA domain, assisting folding and stability of the nascent protein kinase domain [ 63 , 64 ]. Finally, the NLS is not present in DYRK3 and DYRK4 due to alternative splicing [ 65 ].…”

The crystal structure of the protein kinase HIPK2 reveals a unique architecture of its CMGC-insert region

“…Whereas the electron density in this region was poor, preventing us from modeling the side chains, we were able to build the backbone atoms confidently. Hence, HIPK2 appears to engage its N-terminal region in the same pocket as DYRKs while forming a different set of interactions (81,82).…”