Hang Yang | Tu Lab

From Understudied to Understood: Multi-Omics Analysis with MiniENCODE Exemplified by Zebrafish

Mon, 01 Jan 2024 00:00:00 +0000

Abstract: The ENCODE project provides a comprehensive map of genomic activity in humans and mice. However, its extensive toolbox can be too costly and technically challenging for smaller research communities. This presents a hurdle for understudied model organisms where resource constraints and complex omics data integration further compound the challenge. To bridge this gap, our study introduces a miniENCODE project, using the zebrafish as an exemplar. We collected, generated and integrated datasets from three experimental assays across developmental stages and adult tissues. This analysis is facilitated by our newly developed miniODP database, a computational tool designed for the integration and visualization of multi-omics data. Utilizing these methods, we have cataloged over 52,000 candidate enhancers, identified various stage-specific, tissue-specific, and constantly active enhancers, and experimentally validated a subset of heart-specific enhancers. We have delineated key transcription factors and their corresponding regulatory networks across developmental stages and adult tissues. This study not only delivers valuable regulatory insights for the zebrafish research community but also illustrates how an integrative approach can aid in understanding complex regulatory mechanisms even with limited resources. This strategy could empower scientific communities working with various understudied model organisms to expedite their genomic research without overstretching their resources.Competing Interest StatementThe authors have declared no competing interest.

Single-Cell Transcriptome Analysis of the Germ Cells and Somatic Cells during Mitotic Quiescence Stage in Goats

Thu, 30 Nov 2023 00:00:00 +0000

Abstract: The mitotic quiescence of prospermatogonia is the event known to occur during genesis of the male germline and is tied to the development of the spermatogenic lineage. The regulatory mechanisms and the functional importance of this process have been demonstrated in mice; however, regulation of this process in human and domestic animal is still largely unknown. In this study, we employed single-cell RNA sequencing to identify transcriptional signatures of prospermatogonia and major somatic cell types in testes of goats at E85, E105, and E125. We identified both common and specific Gene Ontology categories, transcription factor regulatory networks, and cell-cell interactions in cell types from goat testis. We also analyzed the transcriptional dynamic changes in prospermatogonia, Sertoli cells, Leydig cells, and interstitial cells. Our datasets provide a useful resource for the study of domestic animal germline development.

A Small-Molecule Cocktail Promotes Mammalian Cardiomyocyte Proliferation and Heart Regeneration

Thu, 07 Apr 2022 00:00:00 +0000

Abstract: Zebrafish and mammalian neonates possess robust cardiac regeneration via the induction of endogenous cardiomyocyte (CM) proliferation, but adult mammalian hearts have very limited regenerative potential. Developing small molecules for inducing adult mammalian heart regeneration has had limited success. We report a chemical cocktail of five small molecules (5SM) that promote adult CM proliferation and heart regeneration. A high-content chemical screen, along with an algorithm-aided prediction of small-molecule interactions, identified 5SM that efficiently induced CM cell cycle re-entry and cytokinesis. Intraperitoneal delivery of 5SM reversed the loss of heart function, induced CM proliferation, and decreased cardiac fibrosis after rat myocardial infarction. Mechanistically, 5SM potentially targets α1 adrenergic receptor, JAK1, DYRKs, PTEN, and MCT1 and is connected to lactate-LacRS2 signaling, leading to CM metabolic switching toward glycolysis/biosynthesis and CM de-differentiation before entering the cell-cycle. Our work sheds lights on the understanding CM regenerative mechanisms and opens therapeutic avenues for repairing the heart.

Dynamic Transcriptional and Chromatin Accessibility Landscape of Medaka Embryogenesis

Fri, 26 Jun 2020 00:00:00 +0000

Abstract: Medaka (Oryzias latipes) has become an important vertebrate model widely used in genetics, developmental biology, environmental sciences, and many other fields. A high-quality genome sequence and a variety of genetic tools are available for this model organism. However, existing genome annotation is still rudimentary, as it was mainly based on computational prediction and short-read RNA-seq data. Here we report a dynamic transcriptome landscape of medaka embryogenesis profiled by long-read RNA-seq, short-read RNA-seq, and ATAC-seq. Integrating these datasets, we constructed a much-improved gene model set including about 17,000 novel isoforms, identified 1600 transcription factors, 1100 long non-coding RNAs, and 150,000 potential cis-regulatory elements as well. Time-series datasets provided another dimension of information. With the expression dynamics of genes and accessibility dynamics of cis-regulatory elements, we investigated isoform switching, regulatory logic between accessible elements and genes during embryogenesis. We built a user-friend medaka omics data portal to present these datasets. This resource provides the first comprehensive omics datasets of medaka embryogenesis. Ultimately, we term these three assays as the minimum ENCODE toolbox and propose the use of it as the initial and essential profiling genomic assays for model organisms that have limited data available. This work will be of great value for the research community using medaka as the model organism and many others as well.

Decode-Seq: A Practical Approach to Improve Differential Gene Expression Analysis

Mon, 23 Mar 2020 00:00:00 +0000

Abstract: Many differential gene expression analyses are conducted with an inadequate number of biological replicates. We describe an easy and effective RNA-seq approach using molecular barcoding to enable profiling of a large number of replicates simultaneously. This approach significantly improves the performance of differential gene expression analysis. Using this approach in medaka (Oryzias latipes), we discover novel genes with sexually dimorphic expression and genes necessary for germ cell development. Our results also demonstrate why the common practice of using only three replicates in differential gene expression analysis should be abandoned.