Synapomorphic variations in the THAP domains of human THAP proteins and
their homologs
Abstract
The THAP (Thanatos-associated protein) domain is a DNA-binding domain
which binds DNA via a zinc coordinating C2CH motif. Although THAP
domains share a conserved structural fold, they bind different DNA
sequences in different THAP proteins, which in turn perform distinct
cellular functions. In this study, we investigate (using multiple
sequence alignment, in silico motif and secondary structure prediction)
THAP domain conservation within the homologs of the human THAP (hTHAP)
protein family. We report that there is significant variation in
sequence and predicted secondary structure elements across hTHAP
homologs. Interestingly, we report that the THAP domain can be either
longer or shorter than the conventional 90 residues and the amino
terminal C2CH motif within the THAP domain serves as a hotspot for
insertion or deletion. Our results lay the foundation for future studies
which will further our understanding of the evolution of THAP domain and
regulation of its function.