This family consists of the C-terminal region of several eukaryotic and archaeal RuvB-like 1 (Pontin or TIP49a) and RuvB-like 2 (Reptin or TIP49b) proteins. The N-terminal domain contains the pfam00004 domain. In zebrafish, the liebeskummer (lik) mutation, causes development of hyperplastic embryonic hearts. lik encodes Reptin, a component of a DNA-stimulated ATPase complex. Beta-catenin and Pontin, a DNA-stimulated ATPase that is often part of complexes with Reptin, are in the same genetic pathways. The Reptin/Pontin ratio serves to regulate heart growth during development, at least in part via the beta-catenin pathway. TBP-interacting protein 49 (TIP49) was originally identified as a TBP-binding protein, and two related proteins are encoded by individual genes, tip49a and b. Although the function of this gene family has not been elucidated, they are supposed to play a critical role in nuclear events because they interact with various kinds of nuclear factors and have DNA helicase activities.TIP49a has been suggested to act as an autoantigen in some patients with autoimmune diseases.