MYC and lymphoma: Furthermore, in a separate NF-κB knock in mouse model, where the RelA subunit was engineered to contain a Thr505Ala mutation in its transactivation domain, a site previously shown to affect NF-κB function,40 loss of Bach2 expression was also seen in end-stage lymphoma cells (Figure 3h) but not in 4-week B cells from Eμ-Myc mice (Figure 3i).