Study on Functionally Dynamic Features of Human Secretory Phospholipase A(2)-IIA br

Objective Human secretory phospholipase A2group IIA(sPLA2-IIA)plays an important role in the regulation of cellular lipid metabolism and signal transmission, and participates in a variety of acute and chronicinflammatory responses. Investigating the relationship between their dynamics, allostery and functions is of important significance. Methods The elastic network model(ENM),perturbation-response scanning(PRS)and protein structure network(PSN)methods are utilized to analyze the structural dynamics and allostery of31human sPLA2-IIA members, and explore the relationship between their shared/specific dynamics and functions. Results The results show that the catalytic residues and cysteine residues involved in disulfide bond formation, important for the enzyme's catalysis and structural stability respectively,are of minimal mobility,which are therequirements for the enzyme's shared functions;however,the5regions involved in the association with calciumion/membrane are of high mobility,which embody the specificity of sPLA2-IIA members.Additionally,the PRSanalysis reveals that the above five regions have a high sensitivity to external perturbations,suggesting theirimportant roles in allosteric modulation,while those residues with a low sensitivity play an important role inmaintaining structural stability. Finally,the ANM analysis indicates that the strong correlation movements around the catalytic sites of sPLA2,are helpful for the enzyme's catalytic function exertion. Conclusion This study is helpful for the deep understanding of the dynamics and functionally allosteric mechanism of human sPLA2-IIA,and can provide a guide for drug design and accurate design of proteins with finely tuned activities.