JAK/STAT signaling pathway and its regulation on insect immunity.

JAK/STAT signaling pathway is involved in important biological processes, such as cell growth, differentiation, apoptosis and immune regulation, and is one of the most important signal transduction pathways mediated by cytokines. JAK/STAT is a relatively conserved signaling pathway in insects, which is the main immune pathway together with Toll signaling pathway and Imd signaling pathway to resist the invasion of pathogens. It plays a vital role in insect immunity, hormone regulation and other physiological regulation processes. In this review, we summarize the cytokine receptor superfamily, JAKs family, STATs family, JAK/STAT signaling pathway and its mechanism of negative feedback regulation. We analyze the important functions and the latest research progress of JAK/STAT signaling pathway in insect infected by parasites, viruses and fungi. Finally, we propose the remaining problems in the study of JAK/STAT signaling pathway, so as to provide direction and reference for further research in this field.

Tissue distribution and purification of prophenoloxidase in larvae of Asian Corn Borer, Ostrinia furnacalis Guenee (Lepidoptera: Pyralidae).

Using ammonium sulphate precipitation, Blue-Sepharose CL-6B, Phenyl-Sepharose CL-4B, prophenoloxidase (PPO) was isolated and purified from hemolymph of Ostrinia furnacalis larvae. This zymogen was a heterodimer, and composed of two subunits with the relative molecular mass ranging from 66.2 kD to 97.4 kD determined by SDS-PAGE. Western blotting and indirect immunofluorescence test showed that PPO was present in integument, hemolymph plasma and cell membrane of granular hemocytes and oenocytoids of O. furnacalis larvae.

Purification, crystallization and preliminary X-ray studies of a p-nitrophenylphosphatase from Bacillus stearothermophilus.

Thermostable p-nitrophenylphosphatase from Bacillus stearothermophilus has been expressed in Escherichia coli, purified and crystallized. The crystals belong to space group C(2), with unit-cell parameters a = 67.17 A, b = 57.84 A, c = 62.49 A and alpha = 90.0 degrees, beta = 95.4 degrees, gamma = 90.0 degrees. Diffraction data were collected to 1.40 A resolution with a completeness of 94.7% (96.6% for the last shell), an R(fac) value of 0.074 (0.341) and an I/sigma (I) value of 30.1 (2.67).