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Romero-Moya, D.

Publications and source records attributed to Romero-Moya, D..

5 recordsLinked to original sources

A cold-adapted Cas9 nuclease from the deep ocean

The abundance of CRISPR systems in bacteria and archaea fuels the search for Cas nucleases that perform where established enzymes fail. Deep Ocean 1 Cas9 (DO1Cas9) is to our knowledge the first Cas9 nuclease characterized from the deep ocean, recovered from a metagenomic sample at 1,500 m depth in the Atlantic Ocean. DO1Cas9 shows cold-adapted structural flexibility, thermal susceptibility, salt-dependent stability, higher specificity than SpCas9 and cleaves double-stranded DNA efficiently under cold conditions where mesophilic SpCas9 retains only residual activity. DO1Cas9 edits genomes in diverse organisms such as Caenorhabditis elegans, zebrafish, the marine tunicate Oikopleura dioica, and the malaria parasite Plasmodium falciparum. In the marine bacterium Marinomonas mediterranea, DO1Cas9 programmed against an invading phage reduced plaquing efficiency about 10-fold more than SpCas9. These results expand the CRISPR-Cas9 toolbox with a nuclease for cold-chain editing and marine biotechnology.

genetics↗

TRU-PE: A Universal, Trackable Prime Editor Toolkit for Robust Single- and Multi-Locus Genome Engineering

Prime editing (PE) holds immense promise for precise genome editing, but its wider adoption is constrained by large payloads and inefficient delivery in recalcitrant cell types. Here, we present TRU-PE (Trackable, Robust, and Universal Prime Editor), a toolkit that overcomes these barriers via a split-vector architecture coupled with fluorescence-guided enrichment. This design ensures stoichiometric component expression, yielding marked improvements in editing efficiency and accelerated workflows compatible with both plasmid and viral delivery. By integrating a polycistronic hCtRNA-sgRNA/pegRNA array, the derivative TRU-MPE system enables simultaneous editing of up to ten genomic loci. Furthermore, it enhances the performance of evolved PE editors, allows flexible vector stoichiometry and inspires novel editing reporters. Leveraging these capabilities, we successfully generated a combinatorial human iPSC-based platform for GATA2 deficiency, which accurately recapitulates genotype-specific hematopoietic defects. TRU-PE thus provides a user-friendly, scalable framework for robust single- and multi-locus genome engineering, accelerating functional genomics and therapeutic development.

genetics↗

Staufen2 modulates the temporal dynamics of human neurogenesis in vitro

RNA-binding proteins (RBPs) play a central role in post-transcriptional regulation during brain development, yet their specific functions in coordinating human neural lineage decisions remain poorly understood. Here, we investigate for the first time the role of the double-stranded RBP Staufen2 (STAU2) in human neurogenesis. Characterization of STAU2 knockout iPSC derived cells using scRNA-seq shows that loss of STAU2 disrupts neuroepithelial cell identity and accelerates neural differentiation by altering the activity of key transcription factors and driving early metabolic transitions. Additionally, STAU2 regulates the expression of miRNA host genes and alters miRNA-mediated post- transcriptional control in progenitor cells, which exerts additional effects on STAU2 regulated gene regulatory networks. These changes result in neural progenitor exhaustion, unstructured neural rosettes, and reduced organoid size. Together, our work uncovers a previously unrecognized role for STAU2 as a central regulator of early human neurogenesis, acting through both miRNA-mediated and transcriptional pathways to coordinate progenitor maintenance and neuronal fate specification.

molecular biology↗

Trajectory analysis of hepatic stellate cell differentiation reveals metabolic regulation of cell commitment and fibrosis

Defining the trajectory of cells during differentiation and disease offers the possibility to understand the mechanisms driving cell fate and identity. However, trajectories of human cells are largely unexplored. By investigating the proteome trajectory of iPSCs differentiation to hepatic stellate cells (dHSCs), we identified RORA as a key transcription factor governing the metabolic reprogramming of HSCs necessary for HSCs commitment, identity, and activation. Using RORA deficient iPSCs and pharmacologic interventions, we showed that RORA is required for mesoderm differentiation and prevents dHSCs activation by reducing the high energetic state of the cells. While RORA knockout mice had enhanced fibrosis, RORA agonists rescued multi- organ fibrosis in in vivo models. RORA expression was consistently found to be negatively correlated with liver fibrosis and HSCs activation markers in patients with liver disease. This study reveals that RORA regulates cell metabolic plasticity, crucial for mesoderm differentiation, pericyte quiescence, and fibrosis, influencing cell commitment and disease mechanisms. SummaryThis study describes the trajectory of induced pluripotent stem cells (iPSCs) differentiation to hepatic stellate cells (dHSCs). We identify RAR-related orphan receptor alpha (RORA) as a transcription factor essential for mesoderm commitment and dHSCs identity and fibrogenic activation by regulating metabolic plasticity.

cell biology↗

Increased baseline RASGRP1 signals Enhance Stem Cell Fitness during Native Hematopoiesis

Oncogenic mutations in RAS genes, like KRASG12D or NRASG12D, trap Ras in the active state and cause myeloproliferative disorder and T cell leukemia (T-ALL) when induced in the bone marrow via Mx1CRE. The RAS exchange factor RASGRP1 is frequently overexpressed in T-ALL patients. In T-ALL cell lines overexpression of RASGRP1 increases flux through the RASGTP/RasGDP cycle. Here we expanded RASGRP1 expression surveys in pediatric T-ALL and generated a RoLoRiG mouse model crossed to Mx1CRE to determine the consequences of induced RASGRP1 overexpression in primary hematopoietic cells. RASGRP1-overexpressing, GFP-positive cells outcompeted wild type cells and dominated the peripheral blood compartment over time. RASGRP1 overexpression bestows gain-of-function colony formation properties to bone marrow progenitors in medium containing limited growth factors. RASGRP1 overexpression enhances baseline mTOR-S6 signaling in the bone marrow, but not in vitro cytokine-induced signals. In agreement with these mechanistic findings, hRASGRP1-ires-EGFP enhances fitness of stem- and progenitor- cells, but only in the context of native hematopoiesis. RASGRP1 overexpression is distinct from KRASG12D or NRASG12D, does not cause acute leukemia on its own, and leukemia virus insertion frequencies predict that RASGRP1 overexpression can effectively cooperate with lesions in many other genes to cause acute T cell leukemia.Competing Interest StatementConflict of interest disclosure: Jeroen Roose is a co-founder and scientific advisor of Seal Biosciences, Inc. and on the scientific advisory committee for the Mark Foundation for Cancer Research. C.G.M. receives research funding from Loxo Oncology, Abbvie, and Pfizer, and speaking fees from Amgen. View Full Text

cancer biology↗