Project description:The little skate, a cartilaginous fish evolutionarily distal from tetrapods, displays walking-like behavior and has conserved genetic programs and neuronal substrates for land-walking. Studies on little skate have been limited due to lack of high-quality genome assembly. Here, we generated an improved genome assembly of little skate reflecting precise gene annotation and structures and performed integrated analysis of gene expression and chromatin accessibility to investigate molecular mechanisms of fin motor neuron development. Through interspecies comparison of RNA expression, common and species-specific genes expressed in fin/limb/wing level motor neurons were identified. Moreover, by performing chromatin accessibility analysis with a pure fin motor neuron population the potential regulators controlling the gene expression in fin motor neurons were identified. Interspecies comparison of genomic data, gene expression, and chromatin accessibility assay suggest that the little skate has highly conserved gene regulatory mechanisms controlling tetrapod locomotion, which was not previously expected.
Project description:Rapid and reliable identification of the vertebrate species on which a disease vector previously parasitized is imperative to study ecological factors that affect pathogen distribution and can aid the development of public health programs. We here describe a proteome profiling technique designed to identify the source of blood meals of hematophagous arthropods. This method employs direct spectral matching and thus does not require a priori knowledge of any genetic or protein sequence information. Using this technology, we can detect remnants of blood in blacklegged ticks (Ixodes scapularis) and correctly determine the vertebrate species from which the blood was derived even six months after the tick had fed. This biological fingerprinting methodology is sensitive, fast, cost-effective, and can potentially be adapted for other biological and medical applications when existing genome-based methods are impractical or ineffective.
Project description:The little skate, a cartilaginous fish evolutionarily distal from tetrapods, displays walking-like behavior and has conserved genetic programs and neuronal substrates for land-walking. Studies on little skate have been limited due to lack of high-quality genome assembly. Here, we generated an improved genome assembly of little skate reflecting precise gene annotation and structures and performed integrated analysis of gene expression and chromatin accessibility to investigate molecular mechanisms of fin motor neuron development. Through interspecies comparison of RNA expression, common and species-specific genes expressed in fin/limb/wing level motor neurons were identified. Moreover, by performing chromatin accessibility analysis with a pure fin motor neuron population the potential regulators controlling the gene expression in fin motor neurons were identified. Interspecies comparison of genomic data, gene expression, and chromatin accessibility assay suggest that the little skate has highly conserved gene regulatory mechanisms controlling tetrapod locomotion, which was not previously expected.
Project description:The domestic goat, Capra hircus (2n=60), is one of the most important domestic livestock species in the world. Here we report its high quality reference genome generated by combining Illumina short reads sequencing and a new automated and high throughput whole genome mapping system based on the optical mapping technology which was used to generate extremely long super-scaffolds. The N50 size of contigs, scaffolds, and super-scaffolds for the sequence assembly reported herein are 18.7 kb, 3.06 Mb, and 18.2 Mb, respectively. Almost 95% of the supper-scaffolds are anchored on chromosomes based on conserved syntenic information with cattle. The assembly is strongly supported by the RH map of goat chromosome 1. We annotated 22,175 protein-coding genes, most of which are recovered by RNA-seq data of ten tissues. Rapidly evolving genes and gene families are enriched in metabolism and immune systems, consistent with the fact that the goat is one of the most adaptable and geographically widespread livestock species. Comparative transcriptomic analysis of the primary and secondary follicles of a cashmere goat revealed 51 genes that were significantly differentially expressed between the two types of hair follicles. This study not only provides a high quality reference genome for an important livestock species, but also shows that the new automated optical mapping technology can be used in a de novo assembly of large genomes. Corresponding whole genome sequencing is available in NCBI BioProject PRJNA158393. We have sequenced a 3-year-old female Yunnan black goat and constructed a reference sequence for this breed. In order to improve quality of gene models, RNA samples of ten tissues (Bladder, Brain, Heart, Kidney, Liver, Lung, Lymph, Muscle, Ovarian, Spleen) were extracted from the same goat which was sequenced. To investigate the genic basis underlying the development of cashmere fibers using the goat reference genome assembly and annotated genes, we extracted RNA samples of primary hair follicle and secondary hair follicle from three Inner Mongolia cashmere goats and conducted transcriptome sequencing and DGE analysis. This submission represents RNA-Seq component of study.