Biology subjects

Ramos-Mandujano, G.

Publications and source records attributed to Ramos-Mandujano, G..

2 recordsLinked to original sources

bioRxiv2024

DMSO derives Trophectoderm and Clonal Blastoid from Single Human Pluripotent Stem Cell

Human naive pluripotent stem cells (nPSCs) can differentiate into extra-embryonic trophectoderm (TE), a critical step in the generation of the integrated embryo model termed blastoid. The current paradigm of blastoid generation necessitates the aggregation of dozens of nPSCs treated with multiple small molecule inhibitors, growth factors, or genetic modifications to initiate TE differentiation. The presence of complex crosstalk among pathways and cellular heterogeneity in these models complicates mechanistic study and genetic screens. Here, we show that a single small molecule, dimethyl sulfoxide (DMSO), potently induces TE differentiation in basal medium without pharmacological and genetic perturbations. DMSO enhances blastoid generation and, more importantly, is sufficient for blastoid generation by itself. DMSO blastoids resemble blastocysts in morphology and lineage composition. DMSO induces blastoid formation through PKC signaling and cell cycle regulation. Lastly, DMSO enables single nPSC-derived clonal blastoids, which could facilitate genetic screens for mechanistic understanding of human embryogenesis.

developmental biology↗

bioRxiv2020

Single-cell Individual Complete mtDNA Sequencing Uncovers Hidden Mitochondrial Heterogeneity in Human and Mouse Oocytes

The ontogeny and dynamics of mtDNA heteroplasmy remain unclear due to limitations of current mtDNA sequencing methods. We developed individual Mitochondrial Genome sequencing (iMiGseq) of full-length mtDNA for ultra-sensitive variant detection, complete haplotyping, and unbiased evaluation of heteroplasmy levels, all at the individual mtDNA molecule level. iMiGseq uncovers unappreciated levels of heteroplasmic variants in single healthy human oocytes well below the current 1% detection limit, of which numerous variants are detrimental and could contribute to late-onset mitochondrial disease and cancer. Extreme mtDNA heterogeneity among oocytes of the same mouse female, and a strong selection against deleterious mutations in human oocytes are observed. iMiGseq could comprehensively characterize and haplotype single-nucleotide and structural variants of mtDNA and their genetic linkage in NARP/Leigh syndrome patient-derived cells. Therefore, iMiGseq could not only elucidate the mitochondrial etiology of diseases, but also help diagnose and prevent mitochondrial diseases with unprecedented precision.

genomics↗