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Hudson, J.

Publications and source records attributed to Hudson, J..

4 recordsLinked to original sources

The genome of the Delisea pulchra: a resource for the study of chemical host-microbe interactions in red algae

BackgroundRed macroalgae (Rhodophyta) are ecologically and economically important marine primary producers, yet genomic resources for most species remain scarce. Delisea pulchra, a temperate red alga known for its halogenated furanone-based chemical defenses, serves as a model for studying algal-microbe interactions, antifouling mechanisms, and disease dynamics. ResultsHere we present a high-quality genome assembly of this species. The nuclear genome comprises 134 Mbp across 271 contigs with an N50 of 1.47 Mbp and encodes 13,387 predicted protein-coding genes. Comparative genomics with other red algae revealed expansions in gene families involved in DNA methylation, and oxidative stress responses, including glutathione S-transferases and superoxide dismutases. Analysis of glycosyltransferases, sulfatases, and sulfurylases implicated in galactan biosynthesis suggests D. pulchra possesses a complex and potentially novel extracellular matrix. We also identified several vanadium haloperoxidases (vHPOs), heme-dependent haloperoxidases (hHPOs), and two type III polyketide synthase (PKS) genes unique to the D. pulchra, which together represent promising candidate genes for bromofuranone production. ConclusionThe D. pulchra genome provides a foundation for molecular investigations into defense, signaling, and host-microbe interactions. It has been deposited at the European Nucleotide Archive under accession number PRJEB101077. All datasets, annotations, and interactive tools for exploring the genome are also available through the Rhodoexplorer portal at https://rhodoexplorer.sb-roscoff.fr.

genomics↗

Maturation of human cardiac organoids are required for disease modelling and drug discovery

Cardiac maturation is an important developmental phase culminating in profound biological and functional changes to adapt to the high demand environment after birth1,2. Maturation of human pluripotent stem cell-derived human cardiac organoids (hCO) to more closely resemble human heart tissue is critical for understanding disease pathology. Herein, we profile human heart maturation in vivo3 to identify key signalling pathways that drive maturation in hCOs4,5. Transient activation of both the 5 AMP-activated kinase (AMPK) and estrogen-related receptor (ERR) promoted hCO maturation by mimicking the increased functional demands of post-natal development. hCOs cultured under these directed maturation (DM) conditions (DM-hCOs) display robust transcriptional maturation including increased expression of mature sarcomeric and oxidative phosphorylation genes resulting in enhanced metabolic capacity. DM-hCOs have functionally mature properties such as sarcoplasmic reticulum-dependent calcium handling, accurate responses to drug treatments perturbing the excitation-coupling process and ability to detect ectopy CASQ2 and RYR2 mutants. Importantly, DM- hCOs permit modelling of complex human disease processes such as desmoplakin (DSP) cardiomyopathy, which is driven by multiple cell types. Subsequently, we deploy DM-hCOs to demonstrate that bromodomain extra-terminal inhibitor INCB054329 rescues the DSP phenotype. Together, this study demonstrates that recapitulating in vivo development promotes advanced maturation enabling disease modelling and the identification of a therapeutic strategy for DSP- cardiomyopathy.

bioengineering↗

HOPX governs a molecular and physiological switch between cardiomyocyte progenitor and maturation gene programs

This study establishes the homeodomain only protein, HOPX, as a determinant controlling the molecular switch between cardiomyocyte progenitor and maturation gene programs. Time-course single-cell gene expression with genome-wide footprinting reveal that HOPX interacts with and controls core cardiac networks by regulating the activity of mutually exclusive developmental gene programs. Upstream hypertrophy and proliferation pathways compete to regulate HOPX transcription. Mitogenic signals override hypertrophic growth signals to suppress HOPX and maintain cardiomyocyte progenitor gene programs. Physiological studies show HOPX directly governs genetic control of cardiomyocyte cell stress responses, electro-mechanical coupling, proliferation, and contractility. We use human genome-wide association studies (GWAS) to show that genetic variation in the HOPX-regulome is significantly associated with complex traits affecting cardiac structure and function. Collectively, this study provides a mechanistic link situating HOPX between competing upstream pathways where HOPX acts as a molecular switch controlling gene regulatory programs underpinning metabolic, signaling, and functional maturation of cardiomyocytes.

developmental biology↗

Cardiac directed differentiation using small molecule Wnt modulation at single-cell resolution

Differentiation into diverse cell lineages requires the orchestration of gene regulatory networks guiding diverse cell fate choices. Utilizing human pluripotent stem cells, we measured expression dynamics of 17,718 genes from 43,168 cells across five time points over a thirty day time-course of in vitro cardiac-directed differentiation. Unsupervised clustering and lineage prediction algorithms were used to map fate choices and transcriptional networks underlying cardiac differentiation. We leveraged this resource to identify strategies for controlling in vitro differentiation as it occurs in vivo. HOPX, a non-DNA binding homeodomain protein essential for heart development in vivo was identified as dys-regulated in in vitro derived cardiomyocytes. Utilizing genetic gain and loss of function approaches, we dissect the transcriptional complexity of the HOPX locus and identify the requirement of hypertrophic signaling for HOPX transcription in hPSC-derived cardiomyocytes. This work provides a single cell dissection of the transcriptional landscape of cardiac differentiation for broad applications of stem cells in cardiovascular biology.

developmental biology↗