Expression analysis of the TAB2 protein in adult mouse tissues

BACKGROUND: The Interleukin-1 (IL-1) signaling component TAK1 binding protein 2 (TAB2) plays a role in activating the NFκB and JNK signaling pathways. Additionally, TAB2 functions in the nucleus as a repressor of NFκB-mediated gene regulation. OBJECTIVE: To obtain insight into the function of TAB2 in the adult mouse, we analyzed the in vivo TAB2 expression pattern. MATERIALS AND METHODS: Cell lines and adult mouse tissues were analyzed for TAB2 protein expression and localization. RESULTS: Immunohistochemical staining for TAB2 protein revealed expression in the vascular endothelium of most tissues, hematopoietic cells and brain cells. While TAB2 is localized in both the nucleus and the cytoplasm in cell lines, cytoplasmic localization predominates in hematopoietic tissues in vivo. CONCLUSIONS: The TAB2 expression pattern shows striking similarities with previously reported IL-1 receptor expression and NFκB activation patterns, suggesting that TAB2 in vivo is playing a role in these signaling pathways.