Figure 4

Constitutive phosphorylation of CYLD in HTLV1-transformed T cells. Whole-cell lysates were prepared from control Jurkat T cells or the indicated Tax-expressing (Tax⁺) T cell lines transformed by Tax (Tax1) or HTLV1 (C8166, SLB-1, E55, HUT102) and subjected to IB using anti-CYLD (upper) or anti-IκBα (lower). In lanes 7 and 8, the cell lysates were incubated in vitro with either buffer or calf intestinal phosphatase (CIP) to show that the more slowly migrating protein band is phosphorylated CYLD.