A Highly Scalable Method for Joint Whole-Genome Sequencing and Gene-Expression Profiling of Single Cells

The bovine species buffalo was domesticated from its wild strain Bubalus arnee and is widely used livestock in southern Asia. There are two distinct types of Buffalo- the swamp buffalo (B. bubalis kerebau) and the river buffalo (B. bubalis bubalis), which diverged from the wild Asian water buffalo and then evolved in separate geographical regions. Several research studies performed on buffalo, like- characterization of trait-specific Single Nucleotide Polymorphism (SNP), genetic and phenotypic diversity, gene prediction and function annotation, mapping of the draft genome, have helped our understanding of the buffalo genome. Some advanced discovery as identification of Single Nucleotide Variant (SNVs), Simple Sequence Repeats (SSR) marker and their association with various phenotypic traits, MicroRNA's expression profiling, whole-genome sequencing, etc. have also enabled us to track the chromosomal evolution, physiological processes, and gene expression of buffalo. Proper enhancement of these traits can lead us to apply multi-omics-based tools for better animal health and production. Recent advancement in genomic research on buffalo is being accelerated with the association of modern tools like- Genome-Wide Association Study (GWAS), genotyping by sequencing, epigenomic screening, microRNA's expression profiling, microarray technology, and whole-genome sequencing. All these tools bear great significance in breed up-gradation, identification of the phylogenetic relationship between species in proteome and genomic level, study gene expression level, diagnose diseases or developmental stages, phenotypic diversity, etc. All this knowledge paved the way for better optimization of production efficiency, product quality, and resistance to certain health hazards.

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The crest phenotype in domestic chicken is caused by a 197 bp duplication in the intron of HOXC10

G3 Genes|Genome|Genetics ◽

10.1093/g3journal/jkaa048 ◽

2021 ◽

Author(s):

Jingyi Li ◽

Mi-Ok Lee ◽

Brian W Davis ◽

Ping Wu ◽

Shu-Man Hsieh-Li ◽

...

Keyword(s):

Gene Expression ◽

Whole Genome Sequencing ◽

Diagnostic Test ◽

Genome Sequencing ◽

Ectopic Expression ◽

Body Region ◽

Whole Genome ◽

Dorsal Skin ◽

Conserved Sequence ◽

Evolutionarily Conserved

Abstract The Crest mutation in chicken shows incomplete dominance and causes a spectacular phenotype in which the small feathers normally present on the head are replaced by much larger feathers normally present only in dorsal skin. Using whole genome sequencing, we show that the crest phenotype is caused by a 197 bp duplication of an evolutionarily conserved sequence located in the intron of HOXC10 on chromosome 33. A diagnostic test showed that the duplication was present in all 54 crested chickens representing eight breeds and absent from all 433 non-crested chickens representing 214 populations. The mutation causes ectopic expression of at least five closely linked HOXC genes, including HOXC10, in cranial skin of crested chickens. The result is consistent with the interpretation that the crest feathers are caused by an altered body region identity. The upregulated HOXC gene expression is expanded to skull tissue of Polish chickens showing a large crest often associated with cerebral hernia, but not in Silkie chickens characterized by a small crest, both homozygous for the duplication. Thus, the 197 bp duplication is required for the development of a large crest and susceptibility to cerebral hernia because only crested chicken show this malformation. However, this mutation is not sufficient to cause herniation because this malformation is not present in breeds with a small crest, like Silkie chickens.

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E. coli NF73-1 Isolated From NASH Patients Aggravates NAFLD in Mice by Translocating Into the Liver and Stimulating M1 Polarization

Frontiers in Cellular and Infection Microbiology ◽

10.3389/fcimb.2020.535940 ◽

2020 ◽

Vol 10 ◽

Author(s):

Yifan Zhang ◽

Weiwei Jiang ◽

Jun Xu ◽

Na Wu ◽

Yang Wang ◽

...

Keyword(s):

Gene Expression ◽

Comparative Genomics ◽

Whole Genome Sequencing ◽

Genome Sequencing ◽

Normal Diet ◽

Specific Gene ◽

Whole Genome ◽

Metabolic Switch ◽

M1 Macrophages ◽

E Coli

ObjectiveThe gut microbiota is associated with nonalcoholic fatty liver disease (NAFLD). We isolated the Escherichia coli strain NF73-1 from the intestines of a NASH patient and then investigated its effect and underlying mechanism.Methods16S ribosomal RNA (16S rRNA) amplicon sequencing was used to detect bacterial profiles in healthy controls, NAFLD patients and NASH patients. Highly enriched E. coli strains were cultured and isolated from NASH patients. Whole-genome sequencing and comparative genomics were performed to investigate gene expression. Depending on the diet, male C57BL/6J mice were further grouped in normal diet (ND) and high-fat diet (HFD) groups. To avoid disturbing the bacterial microbiota, some of the ND and HFD mice were grouped as “bacteria-depleted” mice and treated with a cocktail of broad-spectrum antibiotic complex (ABX) from the 8th to 10th week. Then, E. coli NF73-1, the bacterial strain isolated from NASH patients, was administered transgastrically for 6 weeks to investigate its effect and mechanism in the pathogenic progression of NAFLD.ResultsThe relative abundance of Escherichia increased significantly in the mucosa of NAFLD patients, especially NASH patients. The results from whole-genome sequencing and comparative genomics showed a specific gene expression profile in E. coli strain NF73-1, which was isolated from the intestinal mucosa of NASH patients. E. coli NF73-1 accelerates NAFLD independently. Only in the HFD-NF73-1 and HFD-ABX-NF73-1 groups were EGFP-labeled E. coli NF73-1 detected in the liver and intestine. Subsequently, translocation of E. coli NF73-1 into the liver led to an increase in hepatic M1 macrophages via the TLR2/NLRP3 pathway. Hepatic M1 macrophages induced by E. coli NF73-1 activated mTOR-S6K1-SREBP-1/PPAR-α signaling, causing a metabolic switch from triglyceride oxidation toward triglyceride synthesis in NAFLD mice.ConclusionsE. coli NF73-1 is a critical trigger in the progression of NAFLD. E. coli NF73-1 might be a specific strain for NAFLD patients.

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MBRS-59. SINGLE-CELL WHOLE-GENOME SEQUENCING DISSECTS INTRA-TUMOURAL GENOMIC HETEROGENEITY AND CLONAL EVOLUTION IN CHILDHOOD MEDULLOBLASTOMA

Neuro-Oncology ◽

10.1093/neuonc/noaa222.563 ◽

2020 ◽

Vol 22 (Supplement_3) ◽

pp. iii408-iii408

Author(s):

Marina Danilenko ◽

Masood Zaka ◽

Claire Keeling ◽

Stephen Crosier ◽

Rafiqul Hussain ◽

...

Keyword(s):

Whole Genome Sequencing ◽

Single Cell ◽

Genome Sequencing ◽

Copy Number ◽

Single Cell Analysis ◽

Mutational Analysis ◽

Single Cells ◽

Clonal Evolution ◽

Whole Genome ◽

Clinically Significant

Abstract Medulloblastomas harbor clinically-significant intra-tumoral heterogeneity for key biomarkers (e.g. MYC/MYCN, β-catenin). Recent studies have characterized transcriptional heterogeneity at the single-cell level, however the underlying genomic copy number and mutational architecture remains to be resolved. We therefore sought to establish the intra-tumoural genomic heterogeneity of medulloblastoma at single-cell resolution. Copy number patterns were dissected by whole-genome sequencing in 1024 single cells isolated from multiple distinct tumour regions within 16 snap-frozen medulloblastomas, representing the major molecular subgroups (WNT, SHH, Group3, Group4) and genotypes (i.e. MYC amplification, TP53 mutation). Common copy number driver and subclonal events were identified, providing clear evidence of copy number evolution in medulloblastoma development. Moreover, subclonal whole-arm and focal copy number alterations covering important genomic loci (e.g. on chr10 of SHH patients) were detected in single tumour cells, yet undetectable at the bulk-tumor level. Spatial copy number heterogeneity was also common, with differences between clonal and subclonal events detected in distinct regions of individual tumours. Mutational analysis of the cells allowed dissection of spatial and clonal heterogeneity patterns for key medulloblastoma mutations (e.g. CTNNB1, TP53, SMARCA4, PTCH1) within our cohort. Integrated copy number and mutational analysis is underway to establish their inter-relationships and relative contributions to clonal evolution during tumourigenesis. In summary, single-cell analysis has enabled the resolution of common mutational and copy number drivers, alongside sub-clonal events and distinct patterns of clonal and spatial evolution, in medulloblastoma development. We anticipate these findings will provide a critical foundation for future improved biomarker selection, and the development of targeted therapies.

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