DNA sequence motifs are associated with aberrant homologous recombination in the mouse macrophage migration inhibitory factor (Mif) locus

• Published in: Gene Vol. 215; no. 1; pp. 85 - 92
• Main Authors: Kobayashi, Shigetoshi, Yoshida, Kunihiro, Ohshima, Toshio, Esumi, Noriko, Paralkar, Vishwas M, Wistow, Graeme J, Kulkarni, Ashok B
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier B.V 17-07-1998
• Subjects: Adenine Nucleotides - chemistry; Adenine Nucleotides - genetics; Animals; AT-rich sequence; Base Sequence; Binding Sites - genetics; Cell Line; Chromosome Fragility; Consensus Sequence - genetics; Dinucleotide Repeats - genetics; DNA - chemistry; DNA - genetics; DNA Topoisomerases, Type I - genetics; Gene targeting; Genes - genetics; Genes, Intracisternal A-Particle - genetics; Intracisternal-A particle; Macrophage Migration-Inhibitory Factors - genetics; Mice; Mice, Inbred Strains; Microsatellite Repeats - genetics; Molecular Sequence Data; Mutagenesis, Site-Directed; Recombination, Genetic; Sequence Homology, Nucleic Acid; Thymine Nucleotides - chemistry; Thymine Nucleotides - genetics; Topoisomerase I; Gene targeting; ES, embryonic stem; AT-rich sequence; Intracisternal-A particle; Mif, macrophage migration inhibitory factor; IAP, intracisternal-A particle; Topoisomerase I; PCR, polymerase chain reaction; HSV-tk, herpes simplex virus thymidine kinase; LTR, long terminal repeat; PGK, phosphoglycerate kinase
• ISSN: 0378-1119; 1879-0038
• DOI: 10.1016/S0378-1119(98)00271-6

Homologous recombination is a precise genetic event that can introduce specific alteration in the genome. A planned targeted disruption by homologous recombination of the macrophage migration inhibitory factor (
Mif) locus in mouse embryonic stem (ES) cells yielded the targeted clones, some of which had genomic rearrangements inconsistent with the expected homologous recombination event. A detailed characterization of the recombination breakpoints in two of these clones revealed several sequence motifs with possible roles in recombination. These motifs included short regions of sequence identity that may promote DNA alignment, multiple 5′-AAGG/TTCC-3′ tetrameres, topoisomerase I consensus sites, and AT-rich sequences that can promote DNA cleavage and recombination. A retrovirus-like intracisternal-A particle (IAP) family sequence was also identified upstream of the
Mif gene, and the LTR of this IAP was involved in one of the recombinations. Identification and characterization of such sequence motifs will be valuable for the gene targeting experiments.