RNA binding domain of HDV antigen is homologous to the HMG box of SRY

Summary

The delta antigen of hepatitis delta virus exhibits sequence specific binding to its own RNA and is essential for viral replication. Using statistical methods we have detected significant similarity between the RNA-binding domain of the hepatitis delta antigen and the HMG box of SRY. Our analysis suggests that the RNA-binding domain of HDV antigen evolved from the DNA-binding domain of the HMG box. SRY, or a related protein, is a probable cellular cognate of HDV.