Project description:Endoplasmic reticulum (ER) plasticity and ER-phagy are intertwined processes essential for maintaining ER dynamics. We investigated the interplay between two isoforms of the ER-phagy receptor FAM134B in regulating ER remodeling in differentiating myoblasts. During myogenesis, the canonical FAM134B1 is degraded, while its isoform FAM134B2 is transcriptionally upregulated. The switch, favoring FAM134B2, indicates its significance as a regulator of ER morphology during myogenesis. FAM134B2 partial reticulon homology domain, with its rigid conformational characteristics, enables an efficient ER reshaping. FAM134B2 action increases in the active phase of differentiation leading to ER restructuring via ER-phagy, which then reverts to physiological levels when myotubes are mature and the ER reorganized. Knocking out both FAM134B isoforms in myotubes results in aberrant proteome landscape and the formation of dilated ER structures, both of which are rescued by FAM134B2 re-expression. Our results underscore how the fine tuning of FAM134B isoforms and ER-phagy orchestrate the ER dynamics during myogenesis providing insights into the molecular mechanisms governing ER homeostasis in muscle cells.
Project description:Endoplasmic reticulum (ER) plasticity and ER-phagy are intertwined processes essential for maintaining ER dynamics. We investigated the interplay between two isoforms of the ER-phagy receptor FAM134B in regulating ER remodeling in differentiating myoblasts. During myogenesis, the canonical FAM134B1 is degraded, while its isoform FAM134B2 is transcriptionally upregulated. The switch, favoring FAM134B2, indicates its significance as a regulator of ER morphology during myogenesis. FAM134B2 partial reticulon homology domain, with its rigid conformational characteristics, enables an efficient ER reshaping. FAM134B2 action increases in the active phase of differentiation leading to ER restructuring via ER-phagy, which then reverts to physiological levels when myotubes are mature and the ER reorganized. Knocking out both FAM134B isoforms in myotubes results in aberrant proteome landscape and the formation of dilated ER structures, both of which are rescued by FAM134B2 re-expression. Our results underscore how the fine tuning of FAM134B isoforms and ER-phagy orchestrate the ER dynamics during myogenesis providing insights into the molecular mechanisms governing ER homeostasis in muscle cells.
Project description:Naive human pluripotent stem cells (hPSCs) represent a pre-implantation epiblast state able to efficiently differentiate into embryonic and extraembryonic pre-implantation lineages and to self-organise into blastocyst-like structures called blastoids. Naive hPSCs maintenance commonly relies on mouse embryonic fibroblast (MEFs), introducing variability and analytical confounders. Here, we describe a feeder-free culture system based on serum coating that supports long-term naive hPSC maintenance. Across five laboratories, 30 serum batches were evaluated for the expansion of 8 naive hPSC lines for up to 25 passages. Mass spectrometry identified fibronectin and collagens as extracellular matrix proteins consistently present in serum coating. Cells cultured on serum coating displayed growth kinetics, clonogenic capacity, mutation rates, and global gene expression profiles comparable to MEF-based cultures. Importantly, serum-cultured naive hPSCs efficiently underwent germ layer specification, retained trophectoderm competence, and generated blastoids with similar efficiency. Collectively, serum coating provides a scalable, cost-effective, and robust alternative to feeder-based systems, preserving genomic stability and developmental potential while eliminating MEF-associated disadvantages and variability. This platform facilitates large-scale applications of naive hPSCs and enables more reproducible mechanistic studies.
Project description:To investigate differentially expressed lncRNAs in C2C12 myotubes with/without CoCl2 treatment, we used mouse lncRNA microarray to examine the expression of lncRNAs in C2C12 myotubes and C2C12 myotubes with CoCl2 treatment.
Project description:To investigate differentially expressed circRNAs in C2C12 myotubes with/without CoCl2 treatment, we used mouse circRNA microarray to examine the expression of circRNAs in C2C12 myotubes and C2C12 myotubes with CoCl2 treatment.