| 1. |
- Imsland, Freyja, et al.
(författare)
-
Regulatory mutations in TBX3 disrupt asymmetric hair pigmentation underlying Dun camouflage colour in horses
- 2016
-
Ingår i: Nature Genetics. - : Springer Science and Business Media LLC. - 1061-4036 .- 1546-1718. ; 48:2, s. 152-158
-
Tidskriftsartikel (refereegranskat)abstract
- Dun is a wild-type coat color in horses characterized by pigment dilution with a striking pattern of dark areas termed primitive markings. Here we show that pigment dilution in Dun horses is due to radially asymmetric deposition of pigment in the growing hair caused by localized expression of the T-box 3 (TBX3) transcription factor in hair follicles, which in turn determines the distribution of hair follicle melanocytes. Most domestic horses are non-dun, a more intensely pigmented phenotype caused by regulatory mutations impairing TBX3 expression in the hair follicle, resulting in a more circumferential distribution of melanocytes and pigment granules in individual hairs. We identified two different alleles (non-dun1 and non-dun2) causing non-dun color. non-dun2 is a recently derived allele, whereas the Dun and non-dun1 alleles are found in ancient horse DNA, demonstrating that this polymorphism predates horse domestication. These findings uncover a new developmental role for T-box genes and new aspects of hair follicle biology and pigmentation.
|
|
| 2. |
- Kohler, Annegret, et al.
(författare)
-
Convergent losses of decay mechanisms and rapid turnover of symbiosis genes in mycorrhizal mutualists.
- 2015
-
Ingår i: Nature Genetics. - : Springer Science and Business Media LLC. - 1546-1718 .- 1061-4036. ; 47:4, s. 176-410
-
Tidskriftsartikel (refereegranskat)abstract
- To elucidate the genetic bases of mycorrhizal lifestyle evolution, we sequenced new fungal genomes, including 13 ectomycorrhizal (ECM), orchid (ORM) and ericoid (ERM) species, and five saprotrophs, which we analyzed along with other fungal genomes. Ectomycorrhizal fungi have a reduced complement of genes encoding plant cell wall-degrading enzymes (PCWDEs), as compared to their ancestral wood decayers. Nevertheless, they have retained a unique array of PCWDEs, thus suggesting that they possess diverse abilities to decompose lignocellulose. Similar functional categories of nonorthologous genes are induced in symbiosis. Of induced genes, 7-38% are orphan genes, including genes that encode secreted effector-like proteins. Convergent evolution of the mycorrhizal habit in fungi occurred via the repeated evolution of a 'symbiosis toolkit', with reduced numbers of PCWDEs and lineage-specific suites of mycorrhiza-induced genes.
|
|
| 3. |
- Lamichhaney, Sangeet, 1984-, et al.
(författare)
-
Structural genomic changes underlie alternative reproductive strategies in the ruff (Philomachus pugnax)
- 2016
-
Ingår i: Nature Genetics. - : Springer Nature. - 1061-4036 .- 1546-1718. ; 48:1, s. 84-88
-
Tidskriftsartikel (refereegranskat)abstract
- The ruff is a Palearctic wader with a spectacular lekking behavior where highly ornamented males compete for females1,2,3,4. This bird has one of the most remarkable mating systems in the animal kingdom, comprising three different male morphs (independents, satellites and faeders) that differ in behavior, plumage color and body size. Remarkably, the satellite and faeder morphs are controlled by dominant alleles5,6. Here we have used whole-genome sequencing and resolved the enigma of how such complex phenotypic differences can have a simple genetic basis. The Satellite and Faeder alleles are both associated with a 4.5-Mb inversion that occurred about 3.8 million years ago. We propose an evolutionary scenario where the Satellite chromosome arose by a rare recombination event about 500,000 years ago. The ruff mating system is the result of an evolutionary process in which multiple genetic changes contributing to phenotypic differences between morphs have accumulated within the inverted region.
|
|
| 4. |
- Martinez-Arias, Germán, et al.
(författare)
-
Paternal easiRNAs regulate parental genome dosage in Arabidopsis
- 2018
-
Ingår i: Nature Genetics. - : NATURE PUBLISHING GROUP. - 1061-4036 .- 1546-1718. ; 50:2, s. 193-198
-
Tidskriftsartikel (refereegranskat)abstract
- The regulation of parental genome dosage is of fundamental importance in animals and plants, as exemplified by X-chromosome inactivation and dosage compensation. The 'triploid block' is a classic example of dosage regulation in plants that establishes a reproductive barrier between species differing in chromosome number(1,2). This barrier acts in the embryo-nourishing endosperm tissue and induces the abortion of hybrid seeds through a yet unknown mechanism(3). Here we show that depletion of paternal epigenetically activated small interfering RNAs (easiRNAs) bypasses the triploid block in response to increased paternal ploidy in Arabidopsis thaliana. Paternal loss of the plant-specific RNA polymerase IV suppressed easiRNA formation and rescued triploid seeds by restoring small-RNA-directed DNA methylation at transposable elements (TEs), correlating with reduced expression of paternally expressed imprinted genes (PEGs). Our data suggest that easiRNAs form a quantitative signal for paternal chromosome number and that their balanced dosage is required for post-fertilization genome stability and seed viability.
|
|
| 5. |
- Molin, Anna-Maja
(författare)
-
Mutations in ZBTB20 cause Primrose syndrome
- 2014
-
Ingår i: Nature Genetics. - : Springer Science and Business Media LLC. - 1061-4036 .- 1546-1718. ; 46, s. 815-817
-
Tidskriftsartikel (refereegranskat)abstract
- Primrose syndrome and 3q13.31 microdeletion syndrome are clinically related disorders characterized by tall stature, macrocephaly, intellectual disability, disturbed behavior and unusual facial features, with diabetes, deafness, progressive muscle wasting and ectopic calcifications specifically occurring in the former. We report that missense mutations in ZBTB20, residing within the 3q13.31 microdeletion syndrome critical region, underlie Primrose syndrome. This finding establishes a genetic link between these disorders and delineates the impact of ZBTB20 dysregulation on development, growth and metabolism.
|
|
| 6. |
- Mozgova, Iva, et al.
(författare)
-
DNA-sequence-specific erasers of epigenetic memory
- 2016
-
Ingår i: Nature Genetics. - : Springer Science and Business Media LLC. - 1061-4036 .- 1546-1718. ; 48, s. 591-592
-
Annan publikation (refereegranskat)abstract
- How epigenetic regulators find their specific targets remains a challenging question. Two parallel studies show that REF6, a plant H3K27me3 demethylase, binds a specific DNA motif via its zinc-finger domains and recruits the SWI/SNF-type ATPase BRAHMA, demonstrating a sequence-specific recruitment mechanism for a chromatinmodifying complex.
|
|
| 7. |
- Tarekegn, Getinet Mekuriaw
(författare)
-
The mosaic genome of indigenous African cattle as a unique genetic resource for African pastoralism
- 2020
-
Ingår i: Nature Genetics. - : Springer Science and Business Media LLC. - 1061-4036 .- 1546-1718. ; 52, s. 1099-1110
-
Tidskriftsartikel (refereegranskat)abstract
- Whole-genome sequence analysis of 172 indigenous African cattle from 16 breeds identifies 16 loci linked to environmental adaptations among crossbred animals, including a highly divergent locus in African taurine cattle putatively linked to trypanotolerance.Cattle pastoralism plays a central role in human livelihood in Africa. However, the genetic history of its success remains unknown. Here, through whole-genome sequence analysis of 172 indigenous African cattle from 16 breeds representative of the main cattle groups, we identify a major taurine x indicine cattle admixture event dated to circa 750-1,050 yr ago, which has shaped the genome of today's cattle in the Horn of Africa. We identify 16 loci linked to African environmental adaptations across crossbred animals showing an excess of taurine or indicine ancestry. These include immune-, heat-tolerance- and reproduction-related genes. Moreover, we identify one highly divergent locus in African taurine cattle, which is putatively linked to trypanotolerance and present in crossbred cattle living in trypanosomosis-infested areas. Our findings indicate that a combination of past taurine and recent indicine admixture-derived genetic resources is at the root of the present success of African pastoralism.
|
|
| 8. |
- Wilbe, Maria, et al.
(författare)
-
Genome-wide association mapping identifies multiple loci for a canine SLE-related disease complex.
- 2010
-
Ingår i: Nature Genetics. - : Springer Science and Business Media LLC. - 1061-4036 .- 1546-1718. ; 42:3, s. 250-254
-
Tidskriftsartikel (refereegranskat)abstract
- The unique canine breed structure makes dogs an excellent model for studying genetic diseases. Within a dog breed, linkage disequilibrium is extensive, enabling genome-wide association (GWA) with only around 15,000 SNPs and fewer individuals than in human studies. Incidences of specific diseases are elevated in different breeds, indicating that a few genetic risk factors might have accumulated through drift or selective breeding. In this study, a GWA study with 81 affected dogs (cases) and 57 controls from the Nova Scotia duck tolling retriever breed identified five loci associated with a canine systemic lupus erythematosus (SLE)-related disease complex that includes both antinuclear antibody (ANA)-positive immune-mediated rheumatic disease (IMRD) and steroid-responsive meningitis-arteritis (SRMA). Fine mapping with twice as many dogs validated these loci. Our results indicate that the homogeneity of strong genetic risk factors within dog breeds allows multigenic disorders to be mapped with fewer than 100 cases and 100 controls, making dogs an excellent model in which to identify pathways involved in human complex diseases.
|
|
| 9. |
- Wolff, Philip, et al.
(författare)
-
Transposon-derived small RNAs triggered by miR845 mediate genome dosage response in Arabidopsis
- 2018
-
Ingår i: Nature Genetics. - : Springer Science and Business Media LLC. - 1061-4036 .- 1546-1718. ; 50, s. 186-192
-
Tidskriftsartikel (refereegranskat)abstract
- Chromosome dosage has substantial effects on reproductive isolation and speciation in both plants and animals, but the underlying mechanisms are largely obscure(1). Transposable elements in animals can regulate hybridity through maternal small RNA(2), whereas small RNAs in plants have been postulated to regulate dosage response via neighboring imprinted genes(3,4). Here we show that a highly conserved microRNA in plants, miR845, targets the tRNA(Met) primer-binding site (PBS) of long terminal repeat (LTR) retrotransposons in Arabidopsis pollen, and triggers the accumulation of 21-22-nucleotide (nt) small RNAs in a dose-dependent fashion via RNA polymerase IV. We show that these epigenetically activated small interfering RNAs (easiRNAs) mediate hybridization barriers between diploid seed parents and tetraploid pollen parents (the 'triploid block'), and that natural variation for miR845 may account for 'endosperm balance' allowing the formation of triploid seeds. Targeting of the PBS with small RNA is a common mechanism for transposon control in mammals and plants, and provides a uniquely sensitive means to monitor chromosome dosage and imprinting in the developing seed.
|
|
