ABSTRACT: What is an eared nightjar? Ultraconserved elements clarify the evolutionary relationships of Eurostopodus and Lyncornis nightjars (Aves: Caprimulgidae)
Project description:Ultraconserved elements resolve genus-level relationships in a major Australasian bird radiation (Aves: Meliphagidae)
| PRJNA499129 | ENA
Project description:Phylogenomic analysis of evolutionary relationships in Ranitomeya poison frogs (Family Dendrobatidae) using ultraconserved elements
| PRJNA779027 | ENA
Project description:Using ultraconserved elements to unravel lagomorph phylogenetic relationships
Project description:Target enrichment of thousands of ultraconserved elements sheds new light on early relationships within New World sparrows (Aves: Passerellidae)
| PRJNA318526 | ENA
Project description:Disentangling Historical Relationships Within Poeciliidae (Teleostei: Cyprinodontiformes) Using Ultraconserved Elements
Project description:Non-coding ultraconserved regions showing hundreds of consecutive bases of perfect evolutionary sequence conservation across mammalian genomes have intrigued biologists in the decade since they were first described. While many of these sequences are known to represent distant-acting enhancers, initial deletion studies in mice showed that their loss had no obvious impact on viability or fertility. To explore the discrepancy between extraordinary evolutionary constraint and an apparent lack of phenotypes when deleted in vivo, we used genome editing to create an expanded series of knockout mice lacking individual or combinations of ultraconserved brain enhancers near the essential neuronal transcription factor Arx. While the loss of any single or pair of ultraconserved enhancers resulted in viable and fertile mice, detailed phenotyping revealed neurological or growth abnormalities in nearly all cases, including substantial alterations of neuron populations and abnormalities of the dentate gyrus. Our results demonstrate the functional importance of ultraconserved enhancers and highlight that extreme sequence conservation may result from evolutionary selection against fitness deficits that appear subtle in a laboratory setting.
Project description:Topological associating domains (TADs) are self-interacting genomic units crucial for shaping gene regulation patterns. Despite their importance, the extent of their evolutionary conservation and its functional implications remain largely unknown. In this study, we generate Hi-C and ChIP-seq data and compare TAD organization across four primate and four rodent species, and characterize the genetic and epigenetic properties of TAD boundaries in correspondence to their evolutionary conservation. We find 14% of all human TAD boundaries to be shared among all eight species (ultraconserved), while 15% are human-specific. Ultraconserved TAD boundaries have stronger insulation strength, CTCF binding, and enrichment of older retrotransposons, compared to species-specific boundaries. CRISPR-Cas9 knockouts of two ultraconserved boundaries in mouse models leads to tissue-specific gene expression changes and morphological phenotypes. Deletion of a human-specific boundary near the autism-related AUTS2 gene results in upregulation of this gene in neurons. Overall, our study provides pertinent TAD boundary evolutionary conservation annotations, and showcase the functional importance of TAD evolution.
2023-10-20 | GSE197926 | GEO
Project description:Phylogenetic relationships of the Chagas disease vectors Triatominae using Ultraconserved Elements (Hemiptera: Reduviidae)
Project description:The manuscript by D. Licastro and colleagues “Promiscuity of enhancer, coding and non-coding transcription functions in ultraconserved sequence elements” presents an overview of experimental and computational approaches employed by the authors to perform a multi-facet characterization of ultraconserved elements (UCEs). The authors present an interesting analysis where they investigate the transcription of UCEs in mouse development at different stages by conductin an microarray experiment. Some of these results are further verified by RT-PCR.