This domain family is found in eukaryotes, and is approximately 40 amino acids in length. The family is found in association with pfam00076. There are two conserved sequence motifs: TPVCTP and LERRKS. This domain is found on the human nucleolar protein hNIFK. It binds to the fork-head-associated domain of human Ki67. High-affinity binding requires sequential phosphorylation by two kinases, CDK1 and GSK3, yielding pThr238, pThr234 and pSer230. This interaction is involved in cell cycle regulation.