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Farber, G.

Publications and source records attributed to Farber, G..

2 recordsLinked to original sources

Hypothalamic oligodendrocytes regulate systemic energy balance through Notch-dependent state transitions

The central mechanisms through which glial cells regulate whole-body metabolism remain poorly understood. Here, we identify Notch signaling in hypothalamic oligodendrocyte lineage cells as a previously unrecognized regulator of systemic energy homeostasis. Pharmacological inhibition of the Notch ligands Jagged1 (Jag1) and Jagged2 (Jag2) induces rapid and reversible weight loss across diverse physiological and metabolic contexts independently of toxicity or caloric intake. Single-nucleus transcriptomic analyses identify hypothalamic oligodendrocyte precursor cells (OPCs) as the principal Notch-responsive population following systemic Jag1/2 inhibition and reveal expansion of a metabolically specialized GPR17 intermediate state characterized by enhanced oxidative metabolism and increased predicted communication with hypothalamic neurons. This glial remodeling is accompanied by fasting-like transcriptional reprogramming of AgRP neurons, reorganization of melanocortin-autonomic circuit activity, and activation of peripheral catabolic programs. Importantly, selective deletion of Notch1/2 in hypothalamic OPCs recapitulates the major physiological and metabolic effects of systemic Jag1/2 inhibition, establishing oligodendrocyte Notch signaling as a causal regulator of whole-body metabolism. Together, our findings establish Notch-dependent oligodendrocyte state transitions as a previously unrecognized mechanism linking glial plasticity to systemic energy homeostasis.

physiology↗

Charting Postnatal Heart Development Using In Vivo Single-Cell Functional Genomics

The transition at birth, marked by increased circulatory demands and rapid growth, necessitates extensive remodeling of the hearts structure, function, and metabolism. This transformation requires precise spatial and temporal coordination among diverse cardiac cell types; central to this process is cardiomyocyte maturation, yet the regulatory mechanisms driving these changes remain poorly understood. Here, we present a temporal and spatial atlas of postnatal hearts by integrating single-nucleus transcriptomics with image-based spatial transcriptomics, which uncovers the dynamic regulatory networks of cardiomyocyte maturation. To functionally interrogate candidate regulators in vivo, we developed Probe-based Indel-detectable Perturb-seq (PIP-seq), a high-throughput platform that uses probe-based chemistry to directly capture sgRNA expression, perturbation status, and transcriptomic profiles at single-nucleus resolution. Applying PIP-seq to postnatal cardiac development identified 21 novel regulators of cardiomyocyte maturation, highlighting critical nodal points in this process. Our study establishes a high-resolution framework for dissecting postnatal heart development, underscoring the integrative and highly ordered roles of microenvironment and intercellular communication in cardiomyocyte maturation. Importantly, PIP-seq enables systematic, high-throughput exploration of gene function and networks underlying complex biological processes in their native in vivo context.

developmental biology↗