DQX1, an RNA-dependent ATPase homolog with a novel DEAQ box: expression pattern and genomic sequence comparison of the human and mouse genes

DQX1 is a novel gene related to the RNA-dependent ATPases, The gene was cla ssified as a member of the DEAD/H family on the basis of the conserved orde r and spacing of ten short protein motifs. The unique features of DQX1 incl ude replacement of the signature DEAH motif with DEAQ and the absence of th e helicase motif. We determined the coding sequences of human and mouse DQX 1. which encode proteins of 717 and 718 amino acids with 84% amino acid seq uence identity. The 3.2-kb Dqx1 transcript has highest expression in muscle and liver. DQX1 is located between AUP1 and HOX11L1 in a gene-dense region of human Chromosome (Chr) 2p13 and mouse Chr 6. Although DQX1 is within th e nonrecombinant region for the mouse neuromuscular mutant mnd2, no differe nce in coding sequence, transcript length, or transcript abundance was obse rved between normal mice and mnd2 mutant mice. The ubiquitous expression of DQX1 and its close phylogenetic relationship to the yeast pre-mRNA process ing (Prp) proteins suggest a role in cellular RNA metabolism.