HRDC Helicase and RNase D C-terminal
SMART ACC:	SM000341
Description:	Hypothetical role in nucleic acid binding. Mutations in the HRDC domain cause human disease.
InterPro ACC:	IPR002121
InterPro abstract:	The HRDC (helicase and RNaseD C-terminal) domain is comprised of two orthogonally packed α-hairpin subdomains, and is involved in interactions with DNA and protein. It has been suggested that this domain plays a role dissolving double Holliday junctions efficiently [ PUBMED:25901030 ]. HRDC domains are found … expand The HRDC (helicase and RNaseD C-terminal) domain is comprised of two orthogonally packed α-hairpin subdomains, and is involved in interactions with DNA and protein. It has been suggested that this domain plays a role dissolving double Holliday junctions efficiently [ PUBMED:25901030 ]. HRDC domains are found at the C terminus of many RecQ helicases, including the human Bifunctional 3'-5' exonuclease/ATP-dependent helicase WRN and RecQ-like DNA helicase BLM [ PUBMED:25901030 PUBMED:10647186 ]. RecQ helicases have been shown to unwind DNA in an ATP-dependent manner. The structure of the HRDC domain consists of a 4-5 helical bundle of two orthogonally packed α-hairpins, and as such it resembles auxiliary domains in bacterial DNA helicases and other proteins that interact with nucleic acids. A positively charged region on the surface of the HRDC domain is able to interact with DNA. The HRDC domain is also present in eukaryotic and archaeal RNA polymerase II subunit RBP4, the N-terminal of which forms a heterodimerisation α-hairpin [ PUBMED:15591044 PUBMED:11741548 ]. The HRDC domain has a putative role in nucleic acid binding. Mutations in the HRDC domain associated with the human BLM gene result in Bloom Syndrome (BS), an autosomal recessive disorder characterised by proportionate pre- and postnatal growth deficiency; sun-sensitive, telangiectatic, hypo- and hyperpigmented skin; predisposition to malignancy; and chromosomal instability [ PUBMED:9397680 ]. collapse
GO function:	nucleic acid binding (GO:0003676)
Family alignment:	View the Family alignment or the Alignment consensus sequence
There are 17 943 HRDC domains in 17 352 proteins in SMART's NRDB database.

Taxonomic distribution of proteins containing HRDC domains

The tree below includes only several representative species and genera. The complete taxonomic breakdown of all proteins containing HRDC domains can be accessed here. Click the counts or percentage values to display the corresponding proteins.

Relevant references for this domain

Primary literature for the HRDC domain is listed below. Automatically-derived, secondary literature is also available.

KEGG pathways involving proteins which contain this domain

This information is based on the mapping of SMART genomic protein database to KEGG orthologous groups. Percentages are related to the number of proteins containing a HRDC domain which could be assigned to a KEGG orthologous group, and not all proteins containing HRDC domains. Please note that proteins can be included in multiple pathways, ie. the numbers below will not add to 100%.

KEGG pathways

Some of these pathways are included in the interactive Pathways Explorer overview maps. Select an overview map and click the button below to highlight them in iPath.

KEGG orthologous groups

Some of these KOs are included in the interactive Pathways Explorer overview maps. Select an overview map and click the button below to highlight them in iPath.

3D structures in PDB containing this domain

Links to other resources describing this domain

InterPro	IPR002121
Pfam	HRDC