Biology subjects

Gross-Scherf, B.

Publications and source records attributed to Gross-Scherf, B..

3 recordsLinked to original sources

bioRxiv2022

Embryonic cortical layer 5 pyramidal neurons form an active, transient circuit motif perturbed by autism-associated mutations

Cortical circuits are composed predominantly of pyramidal-to-pyramidal neuron connections, yet their assembly during embryonic development is not well understood. We show that embryonic layer 5 pyramidal neurons, identified through single cell transcriptomics, display two phases of circuit assembly in vivo. At E14.5, a multi-layered circuit motif, composed of a single layer 5 cell type, forms. This motif is transient, switching to a second circuit motif, involving all three types, by E17.5. In vivo targeted single cell recordings and two-photon calcium imaging of embryonic layer 5 neurons reveal that, in both phases, neurons have active somas and neurites, tetrodotoxin-sensitive voltage-gated conductances, and functional glutamatergic synapses. Embryonic layer 5 neurons strongly express autism-associated genes, and perturbing these genes disrupts the switch between the two motifs. Hence, layer 5 pyramidal neurons form transient active pyramidal-to-pyramidal circuits, at the inception of neocortex, and studying these circuits could yield insights into the etiology of autism.

neuroscience↗

bioRxiv2019

Cell types of the human retina and its organoids at single-cell resolution: developmental convergence, transcriptomic identity, and disease map

How closely human organoids recapitulate cell-type diversity and cell-type maturation of their target organs is not well understood. We developed human retinal organoids with multiple nuclear and synaptic layers. We sequenced the RNA of 158,844 single cells from these organoids at six developmental time points and from the periphery, fovea, pigment epithelium and choroid of light-responsive adult human retinas, and performed histochemistry. Cell types in organoids matured in vitro to a stable developed state at a rate similar to human retina development in vivo and the transcriptomes of organoid cell types converged towards the transcriptomes of adult peripheral retinal cell types. The expression of disease-associated genes was significantly cell-type specific in adult retina and cell-type specificity was retained in organoids. We implicate unexpected cell types in diseases such as macular degeneration. This resource identifies cellular targets for studying disease mechanisms in organoids and for targeted repair in adult human retinas.

neuroscience↗

bioRxiv2018

Targeting neuronal and glial cell types with synthetic promoter AAVs in mice, non-human primates, and humans

Targeting genes to specific neuronal or glial cell types is valuable both for understanding and for repairing brain circuits. Adeno-associated viral vectors (AAVs) are frequently used for gene delivery, but targeting expression to specific cell types is a challenge. We created a library of 230 AAVs, each with a different synthetic promoter designed using four independent strategies. We show that ~11% of these AAVs specifically target expression to neuronal and glial cell types in the mouse retina, mouse brain, non-human primate retina in vivo, and in the human retina in vitro. We demonstrate applications for recording, stimulation, and molecular characterization, as well as the intersectional and combinatorial labeling of cell types. These resources and approaches allow economic, fast, and efficient cell-type targeting in a variety of species, both for fundamental science and for gene therapy.

neuroscience↗