DEAH box protein 9; ATP-dependent RNA helicase A; nuclear DNA helicase II; NDH II (DHX9, DDX9, LKP, NDH2)

Function

• unwinds double-stranded DNA & RNA in a 3' to 5' direction
• alteration of secondary structure may subsequently influence interactions with proteins or other nucleic acids
• transcriptional activator
• binds MBD2, HRMT1L2/PRMT1, & RELA
• may act to directly link BRCA1, CREBBP or SMN1 & the RNA polymerase II complex
• can also interact with XRCC5 & with TOP2A (RNA dependent)
• interaction with TOP2A is promoted by UBC9
• interaction with histone H2AFX requires phosphorylation of H2AFX on Ser-139
• may be phosphorylated by PRKDC/XRCC7
• phosphorylated upon DNA damage, probably by ATM or ATR

Structure

• the MTAD domain mediates interaction with the RNA polymerase II holoenzyme
• the NTD domain is necessary & sufficient for nuclear- cytoplasmic shuttling & interaction with HRMT1L2 & SMN1
• methylated: HRMT1L2 mediated methylation of undefined Arg in the NTD is required for nuclear localization
• belongs to the DEAD box helicase family, DEAH subfamily
• contains 2 DRBM (double-stranded RNA-binding) domains
• contains 1 helicase ATP-binding domain
• contains 1 helicase C-terminal domain

Compartment

• cytoplasm
• nucleus, nucleolus
• can shuttle between nucleus & cytoplasm

More general terms

• DEAD box ATP-dependent helicase

Database

• UniProt: http://www.uniprot.org/uniprot/Q08211.html
• Entrez gene: http://www.ncbi.nlm.nih.gov/sites/entrez?db=gene&cmd=Retrieve&dopt=Graphics&list_uids=1660
• Kegg: http://www.genome.jp/dbget-bin/www_bget?hsa:1660
• Kegg: http://www.genome.jp/dbget-bin/www_bget?son:SO_3
• OMIM: https://mirror.omim.org/entry/603115