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Sherry, T.

Publications and source records attributed to Sherry, T..

3 recordsLinked to original sources

Atypical TGF-beta Signaling Controls Neuronal Guidance in Caenorhabditis elegans

Coordinated expression of cell adhesion and signaling molecules is crucial for brain development. Here, we report that the Caenorhabditis elegans transforming growth factor-beta (TGF-{beta}) type I receptor SMA-6 (small-6) acts independently of its cognate TGF-{beta} type II receptor DAF-4 (dauer formation-defective-4) to control neuronal guidance. SMA-6 directs neuronal development from the epidermis through interactions with three, orphan, TGF-{beta} ligands. Intracellular signaling downstream of SMA-6 limits expression of NLR-1, an essential Neurexin-like cell adhesion receptor, to enable neuronal guidance. Together, our data identify an atypical TGF-{beta}-mediated regulatory mechanism to ensure correct development of the nervous system.

developmental biology

Harmonization of L1CAM Expression Facilitates Axon Outgrowth and Guidance of a Motor Neuron

Brain development requires precise regulation of axon outgrowth, guidance and termination by multiple signaling and adhesion molecules. How the expression of these neurodevelopmental regulators is transcriptionally controlled is poorly understood. The Caenorhabditis elegans SMD motor neurons terminate axon outgrowth upon sexual maturity and partially retract their axons during early adulthood. Here we show that C-Terminal Binding Protein-1 (CTBP-1), a transcriptional corepressor, is required for correct SMD axonal development. Loss of CTBP-1 causes multiple defects in SMD axon development: premature outgrowth, defective guidance, delayed termination and absence of retraction. CTBP-1 controls SMD axon development by repressing the expression of SAX-7 - a L1 cell adhesion molecule (L1CAM). CTBP-1-regulated repression is crucial as deregulated SAX-7/L1CAM causes aberrant SMD axons. We found that axonal defects caused by SAX-7/L1CAM misexpression are dependent on a distinct L1CAM, called LAD-2, which itself plays a parallel role in SMD axon guidance. Our results reveal that harmonization of L1CAM expression controls the development and maturation of a single neuron.

developmental biology

Diet-responsive Transcriptional Regulation of Insulin in a Single Neuron Controls Systemic Metabolism

To maintain metabolic homeostasis, the nervous system must adapt and respond to an ever-changing environment. Transcription factors are key drivers of this adaptation, eliciting gene expression changes that can alter neuronal activity. Here we show in Caenorhabditis elegans that the terminal selector transcription factor ETS-5 not only establishes the identity of the BAG sensory neurons, but is re-purposed to shape the functional output of the BAG neurons post-mitotically. We find that ETS-5 directly regulates the expression of INS-1, an insulin-like peptide, in the BAG sensory neurons. INS-1 expression in the BAG neurons, and not in other INS-1-expressing neurons, decreases intestinal lipid levels and promotes foraging behaviour. Using in vivo analysis, we show that elevated intestinal lipid stores, driven by a high glucose diet, downregulates ETS-5-driven expression of INS-1. Together, our data reveal an inter-tissue regulatory loop by which a single neuron can control systemic metabolism, and that the activity of this neuron is modulated by the metabolic state of the organism.

genetics