Insights from the molecular docking and simulation analysis of P38 MAPK phytochemical inhibitor complexes.

It is of interest to develop p38α MAPK inhibitors. Docking, ADMET properties calculation, molecular dynamics, and MM-PBSA approaches were used to investigate the therapeutic potentials of p38α MAPK in complex with SB203580 (1A9U). The photo-molecules metergoline, withaphysacarpin, philadelphicalactone, canthin-6-one 9-glucoside, and SB-21600011 demonstrated high binding affinity compared to the reference drug. Furthermore, ADME profiles validated the drug-like properties of the prioritized phyto-compounds. Besides that, MD simulations were performed along with reference inhibitors for withaphysacarpin and metergoline to assess stability. Binding free energy calculations (MM-PBSA) revealed that metergoline and withaphysacarpin had estimated values (G) of 97.151 ± 21.023 kJ/mol and -82.084 ± 15.766 kJ/mol, respectively. In this study, metergoline and withaphysacarpin were found to have high affinity against p38α MAPK when compared to the reference compound SB 203580.

The crystal structure of phosphorylated MAPK13 reveals common structural features and differences in p38 MAPK family activation.

The p38 MAP kinases (p38 MAPKs) represent an important family centrally involved in mediating extracellular signaling. Recent studies indicate that family members such as MAPK13 (p38δ) display a selective cellular and tissue expression and are therefore involved in specific diseases. Detailed structural studies of all p38 MAPK family members are crucial for the design of specific inhibitors. In order to facilitate such ventures, the structure of MAPK13 was determined in both the inactive (unphosphorylated; MAPK13) and active (dual phosphorylated; MAPK13/pTpY) forms. Here, the first preparation, crystallization and structure determination of MAPK13/pTpY are presented and the structure is compared with the previously reported structure of MAPK13 in order to facilitate studies for structure-based drug design. A comprehensive analysis of inactive versus active structures for the p38 MAPK family is also presented. It is found that MAPK13 undergoes a larger interlobe configurational rearrangement upon activation compared with MAPK14. Surprisingly, the analysis of activated p38 MAPK structures (MAP12/pTpY, MAPK13/pTpY and MAPK14/pTpY) reveals that, despite a high degree of sequence similarity, different side chains are used to coordinate the phosphorylated residues. There are also differences in the rearrangement of the hinge region that occur in MAPK14 compared with MAPK13 which would affect inhibitor binding. A thorough examination of all of the active (phosphorylated) and inactive (unphosphorylated) p38 MAPK family member structures was performed to reveal a common structural basis of activation for the p38 MAP kinase family and to identify structural differences that may be exploited for developing family member-specific inhibitors.

Progress in a new proto-oncogene of Wip1 / 中国病理生理杂志

Wip1 is a nuclear protein and a member of serine/threonine specific protein phosphatase type 2C(PP2C)family.It was initially identified as a gene whose expression was induced in response to ? or UV radiation in a p53-dependent manner and a negative feedback regulation of p38MAPK-p53 signaling.Then,Wip1 gene was confirmed a proto-oncogene and amplified or overexpressed in several human tumor types.This review will introduce the structures and functions of Wip1 and details on the signaling process of cancer progression.