Activation segment of protein kinases: classification based on multidimensional analysis.

Activation segments (ASs) of protein kinases play crucial roles in regulation, rendering them prime candidates for therapeutic intervention. Their structural and sequence diversity makes them challenging to study systematically. This study proposes a novel classification of protein kinase ASs based on comprehensive analysis of their sequences, structures and conformational dynamics.

Insights into evolutionary interaction patterns of the 'Phosphorylation Activation Segment' in kinase.

We are interested in studying the phosphorylation of the kinase activation loop, distinguishing the passage from the unphosphorylated to the phosphorylated form without allostery. We performed an interaction study to trace the change of interactions between the activation segment and the kinase catalytic core, before and after phosphorylation. Results show that the structural changes are mainly due to the attraction between the phosphate group and guanidine groups of the arginine side chains of RD-pocket, which are constituted mainly of guanidine groups of the catalytic loop, the β9, and the αC helix.