VIM enhances α-TAT1 degradation through its interaction to suppress the formation of HPIV3 IBs.

(A) α-TAT1 interacted with VIM but not with VIMΔH. Myc–α-TAT1 plasmid was co-transfected with Flag–VIM plasmid or Flag–VIMΔH plasmid in HEK293T cells. Cell lysates were immunoprecipitated using anti-c-Myc tag affinity gel. (B) α-TAT1 interacted with the N–P complex. Myc-α-TAT1, N-Flag, and HA–P plasmid were transfected in HEK293T cells. As IP controls, Myc–α-TAT1 was co-transfected with N-Flag or HA–P. N-Flag or HA–P were individually transfected in groups. Cell lysates were immunoprecipitated using anti-c-Myc tag affinity gel. (C) Localization of VIM, α-TAT1, and HA–P-labeled viral IBs in HeLa cells. HPIV3HA-P virus was used to show viral IBs. Rat APC-anti-FLAG antibody, mouse anti-c-Myc antibody and rabbit anti-HA antibody were used to detect HA–P. The white arrows show the cells with VIM, IBs, and α-TAT1. Scale bar: 20 μm. (D) HA-P was immunoprecipitated with N-Myc, Myc-α-TAT1 and Flag-VIM expressed in 293T cell lysates. (E) VIM enhanced α-TAT1 degradation, but VIMΔH did not. Flag–VIM or Flag–VIMΔH was transfected with Myc–α-TAT1 in WT/VIM-KO cells, and α-TAT1 protein levels were detected. HeLa and A549 cell lines were used to confirm the degradation.