Construction of an integrative regulatory element and variation map of the murine Tst locus.
Given the abundance of new genomic projects and gene annotations, researchers trying to pinpoint causal genetic variants are faced with a challenging task of how to efficiently integrate all current genomic information. The objective of the study was to develop an approach to integrate various genomic annotations for a recently positionally-cloned Tst gene (Thiosulfate Sulfur Transferase, synonym Rhodanese) responsible for the Fob3b2 QTL effect on leanness and improved metabolic parameters. The second aim was to identify and prioritize Tst genetic variants that may be causal for the phenotypic effects.



A bioinformatics approach was developed to integrate existing knowledge of regulatory elements of the Tst gene. The entire Tst locus along with flanking segments was sequenced between our unique polygenic mouse Fat and Lean strains that were generated by divergent selection on adiposity for over 60 generations. The bioinformatics-generated regulatory element map of the Tst locus was then combined with genetic variants between the Fat and Lean mice and with comparative analyses of polymorphisms across 17 mouse strains in order to prioritise likely causal polymorphisms. Two candidate regulatory variants were identified, one overlapping an evolutionary constrained Tst intronic element and the other residing in the seed region of a predicted 3'UTR miRNA binding site.



This study developed a map of regulatory elements for the Tst locus in mice and identified candidate genetic variants with increased causal likelihood. This map provides a basis for experimental validation and functional analyses of this novel candidate leanness and antidiabetic gene. Our methodological approach is of general utility for analyzing regulation of loci that have limited annotations and experimental evidence and for identifying candidate causal regulatory genetic variants in post-GWAS or post-QTL- cloning studies.
Biotechnical Faculty, Animal Science Department, University of Ljubljana, Groblje 3, 1230, Domzale, Slovenia.
Jasmina
J
Beltram
Molecular Metabolism Group, University/British Heart Foundation Centre for Cardiovascular Science, University of Edinburgh, Queen's Medical Research Institute, 47 Little France Crescent, Edinburgh, EH16 4TJ, UK.
Nicholas M
NM
Morton
Biotechnical Faculty, Animal Science Department, University of Ljubljana, Groblje 3, 1230, Domzale, Slovenia.
Tanja
T
Kunej
Biotechnical Faculty, Animal Science Department, University of Ljubljana, Groblje 3, 1230, Domzale, Slovenia. simon.horvat@bf.uni-lj.si.|National Institute of Chemistry, Hajdrihova 19, 1000, Ljubljana, Slovenia. simon.horvat@bf.uni-lj.si.
Simon
S
Horvat
D020413:3' Untranslated Regions; D000818:Animals; D019295:Computational Biology / Q000379:methods; D056426:Genetic Loci; D051379:Mice; D035683:MicroRNAs / Q000378:metabolism; D058977:Molecular Sequence Annotation; D009765:Obesity / Q000235:genetics*; D010641:Phenotype; D040641:Quantitative Trait Loci; D012045:Regulatory Sequences, Nucleic Acid; D017422:Sequence Analysis, DNA; D013851:Thinness / Q000235:genetics*; D013884:Thiosulfate Sulfurtransferase / Q000235:genetics* / Q000378:metabolism
D020413:3' Untranslated Regions; D035683:MicroRNAs; D013884:Thiosulfate Sulfurtransferase
Bioinformatics; Gene variants; Lean; Map; Obesity; Polymorphism; Regulatory elements; Rhodanese; Thiosulfate sulfurtransferase (TST)