Cloning, genomic structure and chromosomal localization of the gene encoding mouse DNA helicase RecQ helicase protein-like 4

Five members of the RecQ helicase family, RECQL, WRN, BLM, RECQL4 and RECQL 5 have been identified in humans. WRN and BLM have been demonstrated to be the responsible genes in Werner and Bloom syndromes, respectively. RECQL4 ( RecQ helicase protein-like 4) was identified as a fourth member of the huma n RecQ helicase family bearing the helicase domain, and it was subsequently shown to be the responsible gene in Rothmund-Thomson syndrome. Here, we is olated mouse RECQL4 and determined the DNA sequence of full-length cDNA as well as the genome organization and chromosome locus. The mouse RECQL4 cons ists of 3651 base pairs coding 1216 amino acid residues and shares 63.4% of identical and 85.8% of homologous amino acid sequences with human RECQL4. The RECQL4 gene was localized to mouse chromosome 15D3 distal-E1 and rat ch romosome 7q34 proximal. They were mapped in the region where the conserved linkage homology has been identified between the two species. Twenty-two ex ons dispersed over 7 kilo base pairs and all of the acceptor and donor site s for splicing of each exon conformed to the GT/AG rule. Our observations r egarding mouse RECQL4 gene will contribute to functional studies on the REC QL4 products. (C) 2000 Elsevier Science B.V. All rights reserved.