Mentor/s:
Andrew Seeds, PhD
Project Title:
Testing the Role of an Interneuron Hemilineage in Drosophila Grooming Behavior
Project Description:
Abnormally repetitive behaviors are hallmark symptoms of disorders like autism spectrum disorder and obsessive-compulsive disorder. These behaviors have been linked to disruptions in specific brain regions that select and execute movement sequences. We study the grooming behavior of Drosophila melanogaster—a predictable sequence of leg movements—as a model for neural organization of sequential actions. Our prior work identified a hemilineage of brain neurons (BNs) that receive input from bristle mechanosensory neurons (BMNs); activating these BNs elicits grooming of specific head locations. We hypothesize these BNs are also necessary for proper grooming behavior. To test this, we integrate structural analysis with functional experimentation. First, we use a Brain and Nerve Cord (BANC) EM dataset to map synaptic connectivity between BMNs and BNs, assessing conservation of grooming circuitry between datasets from different specimens. Second, we conduct experiments involving targeted neuronal inhibition by expressing UAS-hid.z via transgenic driver lines in specific BNs, inducing cell death. Flies coated with dust will then be assessed for grooming ability; impaired grooming would result in dust accumulation on specific head regions. Determining the necessity of these BNs in grooming will enhance our understanding of how neural circuits contribute to sequential actions. This has implications for understanding behavioral sequences in more complex organisms and may offer insights into the neural circuitry of disorders characterized by abnormally repetitive behaviors.
Mentor/s:
Matthew Wood, PhD, Jonathon Blake Schofield
Project Title:
Determining an Optimal Lectin for Blood Vessel Labeling In Regenerating Rat Sciatic Nerve Whole Mounts
Project Description:
Segmental nerve injuries, characterized by nerve gaps, can spontaneously regenerate and restore function in rodents when the gap ranges between 2–3 mm. This regeneration process involves a highly coordinated sequence of events, including intricate crosstalk among Schwann cells, blood vessels, macrophages, and regenerating axons. To better study these interactions, we aim to employ multicolor wholemount staining of the regenerating nerve bridge, preserving spatial arrangements of blood vessels, Schwann cell tracks, and axons. However, assembling a multicolor staining panel is challenging due to the need for suitable antibodies and the potential for cross-reactivity. In this study, we sought to identify a blood vessel label to complete our five-color panel. We tested several commonly used fluorophore conjugated lectins—Lycopersicon esculentum agglutinin (LEA), Griffonia simplicifolia lectin II (GSL-II), and Isolectin B4 (IB4)—through staining and intravenous injection at varying concentrations. An established RECA-1 antibody served as a positive control to assess staining overlap and compare signal-to-noise ratio (SNR). Our results indicated that IV injection of 250–500 μg of IB4 yielded the strongest overlap with RECA-1 staining and exhibited a higher SNR compared to RECA-1.