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Amamoto, R.

Publications and source records attributed to Amamoto, R..

3 recordsLinked to original sources

Retinoic acid signaling mediates peripheral cone photoreceptor survival in a mouse model of retina degeneration

Retinitis Pigmentosa (RP) is a wide array of progressive, debilitating visual disorders caused by mutations in a diverse set of genes. In both human patients and mouse models of RP, rod photoreceptor dysfunction leads to loss of night vision, and is followed by secondary cone photoreceptor dysfunction and degeneration, leading to loss of daylight color vision. A strategy to prevent secondary cone death could provide a generalized RP therapy to preserve daylight color vision regardless of the underlying mutation. In mouse models of RP, cones in the far peripheral retina survive long-term, despite complete rod loss. The mechanism for such peripheral cone survival had not been explored. Here, we found that active retinoic acid (RA) signaling in peripheral Muller glia is both sufficient and necessary for the extended cone survival. RA depletion by conditional knockout of RA synthesis enzymes, or overexpression of an RA degradation enzyme, abrogated peripheral cone survival. Conversely, constitutive activation of RA signaling in the central retina promoted long-term cone survival. These results indicate that RA signaling mediates the prolonged peripheral cone survival in the rd1 mouse model of retinal degeneration, and provide a basis for a generic strategy for cone survival in the many diseases that lead to loss of cone-mediated vision.

developmental biology↗

Probe-Seq enables transcriptional profiling of specific cell types from heterogeneous tissue by RNA-based isolation

Recent transcriptional profiling technologies are uncovering previously-undefined cell populations and molecular markers at an unprecedented pace. While single cell RNA (scRNA) sequencing is an attractive approach for unbiased transcriptional profiling of all cell types, a complementary method to isolate and sequence specific cell populations from heterogeneous tissue remains challenging. Here, we developed Probe-Seq, which allows deep transcriptional profiling of specific cell types isolated using RNA as the defining feature. Dissociated cells are labelled using fluorescent in situ hybridization (FISH) for RNA, and then isolated by fluorescent activated cell sorting (FACS). We used Probe-Seq to purify and profile specific cell types from mouse, human, and chick retinas, as well as the Drosophila midgut. Probe-Seq is compatible with frozen nuclei, making cell types within archival tissue immediately accessible. As it can be multiplexed, combinations of markers can be used to create specificity. Multiplexing also allows for the isolation of multiple cell types from one cell preparation. Probe-Seq should enable RNA profiling of specific cell types from any organism.

molecular biology↗

FIN-Seq: Transcriptional profiling of specific cell types in frozen archived tissue from the human central nervous system

Thousands of frozen, archived tissues from postmortem human central nervous system (CNS) are currently available in brain banks. As single cell and single nucleus technologies are beginning to elucidate the cellular diversity present within the human CNS, it is becoming clear that transcriptional analysis of the human CNS requires cell type specificity. Single cell and single nucleus RNA profiling provide one avenue to decipher this heterogeneity. An alternative, complementary approach is to profile isolated, pre-defined cell types and use methods that can be applied to many archived human tissue samples. Here, we developed FIN-Seq (Frozen Immunolabeled Nuclei Sequencing), a method that accomplishes these goals. FIN-Seq uses immunohisto-chemical isolation of nuclei of specific cell types from frozen human tissue, followed by RNA-Sequencing. We applied this method to frozen postmortem samples of human cerebral cortex and retina and were able to identify transcripts, including low abundance transcripts, in specific cell types.

neuroscience↗