string: …protein interaction domains, one being a broad-complex tramtrack bric-a-brac/POX virus and zinc finger domain (BTB/POZ) at the N-terminal and the other being ankyrin repeat domain (ARD) in the middle of the protein (Aravind and Koonin 1999; Cao et al. 1997; Kinkema et al. 2000; Mou et al. 2003).