bioRxiv Science⌕ Search

bioRxiv · 10.1101/171777

Adiposity QTL Adip20 decomposes into at least four loci when dissected using congenic strains

Abstract

An average mouse in midlife weighs between 25 and 30 g, with about a gram of tissue in the largest adipose depot (gonadal), and the weight of this depot differs between inbred strains. Specifically, C57BL/6ByJ mice have heavier gonadal depots on average than do 129P3/J mice. To understand the genetic contributions to this trait, we mapped several quantitative trait loci (QTLs) for gonadal depot weight in an F2 intercross population. Our goal here was to fine-map one of these QTLs, Adip20 (formerly Adip5), on mouse chromosome 9. To that end, we analyzed the weight of the gonadal adipose depot from newly created congenic strains. Results from the sequential comparison method indicated at least four rather than one QTL; two of the QTLs were less than 0.5 Mb apart, with opposing directions of allelic effect. Different types of evidence (missense and regulatory genetic variation, human adiposity/body mass index orthologues, and differential gene expression) implicated numerous candidate genes from the four QTL regions. These results highlight the value of mouse congenic strains and the value of this sequential method to dissect challenging genetic architecture.

Source connections

Explore related subjects

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

Lin, C., Fesi, B. D., Marquis, M., Bosak, N. P., Lysenko, A., Koshnevisan, M. A., Duke, F. F., Theodorides, M. L., Nelson, T. M., McDaniel, A. H., Avigdor, M., Arayata, C. J., Shaw, L., Bachmanov, A. A., Reed, D. R.. 2017-08-02. Adiposity QTL Adip20 decomposes into at least four loci when dissected using congenic strains. https://doi.org/10.1101/171777

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related preprints

Mapping, stacking and characterization of a novel resistance haplotype against GpaVvrn-virulent Globodera pallida derived from wild potato relative Solanum brevicaule

Potato production is threatened by pests and pathogens. Among the most harmful are the potato cyst nematodes (PCN), including Globodera pallida. The major control measures are potato cultivars harbouring resistance genes. However, virulent nematode populations are breaking through the most broadly applied resistance genes, and therefore novel resistance genes are required to keep control of G. pallida. In this study we map a resistance locus in wild potato relative Solanum brevicaule to the bottom of chromosome 11 (42.83 - 42.85 Mb) using a k-mer based bulked segregant analysis and name the resistant haplotype GpaXIbrc. The presence of the GpaXIbrc marker in the potato genome significantly increases resistance against a GpaVvrn-virulent G. pallida population (AMPOP01). Furthermore, the GpaXIbrc haplotype was stacked with three other resistance haplotypes: GpaXItar, GpaVvrn, and GpaIXvrn. Stacking of the novel GpaXIbrc haplotype to these other resistance haplotypes resulted in a significant increase in resistance. The largest effect was seen in combinations with 'major' resistance haplotypes GpaVvrn + GpaIXvrn and GpaXItar + GpaXIbrc. To determine whether we are dealing with a novel allele, the resistance mechanism underlying the GpaXIbrc haplotype was described after performing an in vitro bioassay. The resistance mechanism was different from GpaXIspl as described in literature, which is also localized at the bottom of chromosome 11. Therefore, we conclude that we found a novel resistance allele originating from S. brevicaule.

genetics↗

Multiple domains of Mata1 transcription factor contribute to binding site specificity

Among homologous transcription factors with the same function, DNA-binding specificity can diverge. Mat1 is a high mobility group (HMG) box transcription factor in budding yeast whose Saccharomyces cerevisiae and Candida albicans homologs regulate -specific genes but bind distinct cis-regulatory sequences. To identify the protein features underlying this divergence, we generated structure-guided chimeras and measured their activity using species-specific reporters. Replacing any of the four Mat1 regions reduced activation of the S. cerevisiae reporter, while all chimeras retained activity on the C. albicans reporter. Thus, all four regions of Mat - not just the HMG box domain - are important for sequence specificity.

genetics↗

A multi-tissue RNA-seq atlas of adult medaka (Oryzias latipes) under salinity and winter-summer sampling contrasts

Medaka (Oryzias latipes) is a euryhaline and eurythermal teleost widely used in genetics and environmental biology. We generated an RNA-sequencing atlas of 11 adult tissues (brain, eye, gill, heart, intestine, kidney, liver, muscle, spleen, ovary, testis) of the strain d-rR/TOKYO, sampled under two independent environmental contrasts: salinity (freshwater versus seawater) and season (winter versus summer). The freshwater and summer groups, reared indoors and outdoors under long days, provide a third contrast between laboratory and outdoor rearing. Typically, one male and one female were sampled per condition, with ten tissues taken from each individual. Ninety libraries were quantified against the medaka RefSeq transcript set (GCF_053564925.1). The resource comprises gene-level TPM and count matrices, differential expression tables for each tissue and contrast, tissue-specificity indices, human ortholog annotations, sample metadata, and a self-contained interactive browser. Because replication is limited and each condition was sampled on its own date, the differential expression tables are intended for hypothesis generation. The dataset supports studies of gene-expression plasticity and comparisons between medaka and humans.

genetics↗