This entry represents the CUE domain found at the N terminus of N4BP2.N4BP2 has been identified as BCL-3-binding protein (B3BP), a protein that interacts with the bcl-3 gene product and participates in connecting transcriptional activation and genetic recombination of the Ig gene []. In addition to BCL-3, it also interacts with p300/CBP histone acetyltransferases. N4BP2 shows intrinsic ATP binding and hydrolyzing activity. It contains an N-terminal ATP-binding region that is responsible for the interaction with BCL-3 and p300/CBP. N4BP2 also functions as a 5'-polynucleotide kinase that can transfer a phosphate group to the 5' end of DNA and RNA substrates. Moreover, N4BP2 contains a C-terminal MutS-related domain that possesses nicking endonuclease activity and may play a role in DNA mismatch repair (MMR) [].
