ABSTRACT
Whole-genome radiation hybrids have been used to construct human genome maps that integrate different types of markers. To investigate this methodology in mammalian species other than humans, a panel of 164 mouse x hamster whole-genome radiation hybrids was constructed. This set of hybrids was used to produce a high-resolution map of a region on MMU11 that included microsatellite markers and cDNA sequences. The mouse homologue of the human SRY-related gene SOX9 was mapped to an interval of approximately 1.1 cM flanked by the microsatellite markers D11Mit11 and D11Mit291. This interval includes the region containing the mouse Tail-short mutation, a possible homologue of the human syndrome campomelic dysplasia, which is caused by mutations in SOX9. Our results suggest that whole-genome radiation hybrid technology will be a useful adjunct to mapping the genomes of nonhuman mammalian species.
Subject(s)
Chromosome Mapping , Genome , Mice/genetics , Animals , Base Sequence , Cricetinae , DNA Primers , DNA, Satellite , Genetic Markers , High Mobility Group Proteins/genetics , Humans , Hybrid Cells/radiation effects , Male , Mice, Mutant Strains , Molecular Sequence Data , Polymerase Chain Reaction , SOX9 Transcription Factor , Sex Differentiation , Stem Cells/radiation effects , Transcription Factors/geneticsABSTRACT
We have constructed a whole genome radiation hybrid (WG-RH) map across a region of human chromosome 17q, from growth hormone (GH) to thymidine kinase (TK). A panel of 128 WG-RH hybrid cell lines generated by X-irradiation and fusion has been tested for the retention of 39 sequence-tagged site (STS) markers by the polymerase chain reaction. This genome mapping technique has allowed the integration of existing VNTR and microsatellite markers with additional new markers and existing STS markers previously mapped to this region by other means. The WG-RH map includes eight expressed sequence tag (EST) and three anonymous markers developed for this study, together with 23 anonymous microsatellites and five existing ESTs. Analysis of these data resulted in a high-density comprehensive map across this region of the genome. A subset of these markers has been used to produce a framework map consisting of 20 loci ordered with odds greater than 1000:1. The markers are of sufficient density to build a YAC contig across this region based on marker content. We have developed sequence tags for both ends of a 2.1-Mb YAC and mapped these using the WG-RH panel, allowing a direct comparison of cRay6000 to physical distance.
Subject(s)
Chromosomes, Human, Pair 17 , Growth Hormone/genetics , Thymidine Kinase/genetics , Animals , Base Sequence , Cell Line , Chromosome Mapping , Cricetinae , DNA Primers , Genetic Markers , Humans , Molecular Sequence Data , Sequence Tagged SitesABSTRACT
In radiation hybrid mapping, chromosomes in human-rodent hybrid cells are fragmented by X-rays and fragments rescued by fusion of the donor cell to a recipient rodent cell. The co-retention frequencies of markers in 100-200 hybrids are used to map individual chromosomes, but mapping the whole genome in this way is impractical. We have reverted to the original protocols of Goss and Harris and have produced a panel of 44 hybrids using irradiated human fibroblasts as donors. This panel has been used to make a map of human chromosome 14 containing 40 ordered markers. The map integrates previously published maps and localizes nine new markers. We suggest that the construction of a high resolution map of the whole human genome is feasible with a single panel of 100-200 hybrids.
Subject(s)
Chromosome Mapping/methods , Chromosomes, Human , Genome, Human , Hybrid Cells , Animals , Base Sequence , CHO Cells , Cell Fusion , Cell Line , Chromosomes, Human/radiation effects , Chromosomes, Human, Pair 14 , Cricetinae , Cricetulus , Diploidy , Fibroblasts/radiation effects , Fibroblasts/ultrastructure , Genetic Markers , HumansABSTRACT
Following infection by the malaria parasite, human erythrocytes show increased uptake of a wide variety of low molecular weight solutes via pathways with functional characteristics different from those of the transporters of normal erythrocytes. In this study glibenclamide and meglitinide were shown to inhibit the induced transport of a sugar alcohol (sorbitol), an amino acid (threonine), an inorganic anion (Cl-) and an organic cation (choline) into human erythrocytes infected in vitro with Plasmodium falciparum. The results are consistent with the hypothesis that a diverse range of substrates enter malaria-infected cells via common pathways which have features in common with Cl- channels in other cell types. glibenclamide and meglitinide were also shown to inhibit the in vitro growth of the intracellular parasite which would suggest that these pathways may be a viable chemotherapeutic target.