PROSITE documentation PDOC50967

HRDC domain profile

The helicase and RNaseD C-terminal (HRDC) domain is an 80-amino acid domain usually found at the C-terminus of RecQ helicases and RNase D homologs from various organisms, including human, yeast and bacteria [1]. The HRDC domain is involved in the binding of DNA to specific DNA structures (e.g. long-forked duplexes and Holliday junctions) that are formed during replication, recombination or transcription [2].

The 3D structure of the HRDC domain consists of five helices (see <PDB:1D8B>). Conserved residues in all five helices are important for the packing of the HRDC fold [3].

Some proteins known to contain a HRDC domain are listed below:

• Animal Werner syndrome helicase (WRN). In human, defects in WRN are the cause of Werner syndrome (WS), a rare autosomal recessive progeroid syndrome characterized by the premature onset of multiple age-related disorders.
• Animal Bloom's syndrome protein (EC 3.6.1.-) (BLM). In human, defects in BLM are the cause of Bloom syndrome (BS), an autosomal recessive disorder characterized by proportionate pre- and postnatal growth deficiency, sun- sensitive telangiectatic hypo- and hyperpigmented skin, predisposition to malignancy, and chromosomal instability.
• Human PM-Scl autoantigen.
• Yeast SGS1, the ortholog of BLM. It is required for chromosome segregation and interacts with topoisomerases I and II.

The profile we developed covers the entire HRDC domain.