Interaction between Litopenaeus vannamei Rab5B protein (LvRab5B) and IHHNV proteins

To study the antiviral function of LvRab5B in the virus resistance of Litopenaeus vannamei, we constructed the fusion expression vectors of LvRab5B protein in insect cells and in yeast cells, respectively; studied the expression of LvRab5B protein in insect cells using immunofluorescence technique; studied the interaction between LvRab5B protein and IHHNV proteins using yeast two-hybrid technique; studied the expression of LvRab5B in different tissues of normal L. vannamei and the relative expression of LvRab5B at different time points after infection in L. vannamei infected with IHHNV or WSSV using qRT-PCR technique. The results showed that the fusion LvRab5B protein was able to express in insect cells. LvRab5B protein had no interaction with capsid protein (CP) of IHHNV, while it interacted with nonstructural protein (NS1) of IHHNV, and was weakly interacted with nonstructural protein (NS2) of IHHNV. qRT-PCR showed that LvRab5B was expressed in the heart, gills, intestine, stomach, hepatopancreas and muscle of normal L. vannamei, and the expression was the highest in the intestine, followed by the hepatopancreas. The relative expression of LvRab5B was different after viral infection. The expression decreased at the initial stage of infection, then increased rapidly, finally decreased at the end stage. This study shows that LvRab5B is involved in the innate immune process of L. vannamei against IHHNV or WSSV infection, which lays a foundation for further studies of the immune function and mechanism of LvRab5B protein in shrimp.