# positions[].label
Acting Associate Provost for Graduate & Professional Studies

# positions[].organizations[].label
Office of the Provost and Executive Vice President

# overview
Cellular and Developmental Neurobiology

Research Summary My laboratory studies cellular mechanisms governing the formation of specific synaptic connections between neurons and their targets. These mechanisms include cell-cell recognition and target-dependent induction of the presynaptic secretion machinery. Some of our studies investigate synapse formation of identified motoneurons of the American pond snail, Helisoma trivolvis , following nerve injury in vivo and in cell culture. Since the synapse is the site of most interneuronal communication within the nervous system, an understanding of the development, regeneration and plasticity of these connections is crucial to an ultimate appreciation of neural integration and brain function.

Neural Morphallaxis

We also study a rare form of regeneration called neural morphallaxis in the annelid worm, Lumbriculus variegatus. This organism is ideal for examining behavioral, physiological, cellular and molecular mechanisms of development, regeneration and systems-level plasticity. We have defined the neural correlates of escape reflexes, which are reconfigured during morphallaxis. Recently we have begun investigations of synaptic molecules up-regulated specifically during morphallaxis. This model system is emerging as a valuable educational tool in the science classroom.

# keywords[]
5 Development Of Treatments And Therapeutic Interventions

# keywords[]
1.1 Normal Biological Development And Functioning

# educationAndTraining[].organization.label
Augustana College - (Sioux Falls, South Dakota, United States)

# educationAndTraining[].organization.label
Iowa State University - (Ames, Iowa, United States)

# educationAndTraining[].organization.label
Illinois State University - (Normal, Illinois, United States)

# educationAndTraining[].organization.label
Iowa State University - (Ames, Iowa, United States)

# awardsAndHonors[].label
Association of Former Students College-Level Teaching Distinguished Achievement Award, The

# publications[].label
Modulation of intercellular calcium signaling by melatonin in avian and mammalian astrocytes is brain region‐specific

# publications[].label
Target-dependent induction of secretory capabilities in an identified motoneuron during synaptogenesis.

# publications[].label
A relation between synaptic specificity and the acquisition of presynaptic properties.

# publications[].label
Cellular mechanisms governing synapse formation: Lessons from identified neurons in culture

# publications[].label
Regeneration of Rapid Escape Reflex Pathways in Earthworms

# publications[].label
The in vivo function of Drosophila CMP-Sialic acid synthetase

# publications[].label
Asexual reproduction and segmental regeneration, but not morphallaxis, are inhibited by boric acid in Lumbriculus variegatus (Annelida : Clitellata : Lumbriculidae)

# publications[].label
Drosophila CRY Entrains Clocks in Body Tissues to Light and Maintains Passive Membrane Properties in a Non-clock Body Tissue Independent of Light.

# publications[].label
Coupled sensory interneurons mediate escape neural circuit processing in an aquatic annelid worm, Lumbriculus variegatus

# publications[].label
Lumbriculus variegatus and the Need for Speed: A Model System for Rapid Escape, Regeneration and Asexual Reproduction

# publications[].label
Teratogenic effects of the fungicide benomyl on posterior segmental regeneration in the earthworm, Eisenia fetida

# publications[].label
Neurobehavioral specializations for respiratory movements and rapid escape from predators in posterior segments of the tubificid Branchiura sowerbyi

# publications[].label
Giant axon morphallaxis during segmental regeneration of Lumbriculus variegatus.

# publications[].label
Rapid escape reflexes in aquatic oligochaetes: variations in design and function of evolutionarily conserved giant fiber systems

# publications[].label
FMRFamide modulation of secretory machinery underlying presynaptic inhibition of synaptic transmission requires a pertussis toxin-sensitive G-protein.

# publications[].label
Specific muscle contacts induce increased transmitter release and neuritic arborization in motoneuronal cultures.

# publications[].label
Regeneration and asexual reproduction share common molecular changes: upregulation of a neural glycoepitope during morphallaxis in Lumbriculus.

# publications[].label
Regulation and restoration of motoneuronal synaptic transmission during neuromuscular regeneration in the pulmonate snail Helisoma trivolvis.

# publications[].label
The role of Drosophila cytidine monophosphate-sialic acid synthetase in the nervous system.

# publications[].label
Lumbriculus variegatus and the Need for Speed: A Model System for Rapid Escape, Regeneration and Asexual Reproduction

# publications[].label
A neuromodulator of synaptic transmission acts on the secretory apparatus as well as on ion channels.

# publications[].label
Manganese suppresses ATP-dependent intercellular calcium waves in astrocyte networks through alteration of mitochondrial and endoplasmic reticulum calcium dynamics.

# publications[].label
Mitochondrial calcium signaling mediates rhythmic extracellular ATP accumulation in suprachiasmatic nucleus astrocytes.

# publications[].label
Creating Teaching Opportunities for STEM Future Faculty Development

# publications[].label
The role of CMP-Sialic acid synthetase in Drosophila neural transmission

# publications[].label
Circadian rhythms of extracellular ATP accumulation in suprachiasmatic nucleus cells and cultured astrocytes.

# publications[].label
Rapid neural circuit switching mediated by synaptic plasticity during neural morphallactic regeneration

# publications[].label
Effects of nerve injury and segmental regeneration on the cellular correlates of neural morphallaxis

# publications[].label
Activity-dependent induction of functional secretory properties at cultured neuromuscular synapses of Helisoma

# publications[].label
Short-term and long-term alterations in neuronal excitability during injury-induced axonal regeneration in ganglia and cell culture

# publications[].label
Transient electrical coupling regulates formation of neuronal networks.

# publications[].label
sublethal neurotoxic effects of the fungicide benomyl on earthworms (Eisenia fetida)

# publications[].label
Electrical synapse formation disrupts calcium‐dependent exocytosis, but not vesicle mobilization

# publications[].label
Formation and modulation of chemical connections: evoked acetylcholine release from growth cones and neurites of specific identified neurons.

# publications[].label
Circadian rhythms from multiple oscillators: lessons from diverse organisms.

# publications[].label
Daily and circadian variation in the electroretinogram of the domestic fowl: effects of melatonin.

# publications[].label
Serotonin regulates electrical coupling via modulation of extrajunctional conductance: H-current.

# publications[].label
Target contact regulates the calcium responsiveness of the secretory machinery during synaptogenesis.

# publications[].label
The lateral giant fibers of the tubificid worm, Branchiura sowerbyi: Structural and functional asymmetry in a paired interneuronal system

# publications[].label
Transient electrical coupling delays the onset of chemical neurotransmission at developing synapses.

# publications[].label
Retrograde regualtion of presynaptic development during synaptogenesis

# publications[].label
Melatonin modulates intercellular communication among cultured chick astrocytes.

# publications[].label
Neurobehavioral specializations for respiratory movements and rapid escape from predators in posterior segments of the tubificid Branchiura sowerbyi

# publications[].label
Sialyltransferase regulates nervous system function in Drosophila.

# publications[].label
Neuron-muscle contact changes presynaptic resting calcium set-point.

# publications[].label
Aminergic and peptidergic modulation of motor function at an identified neuromuscular junction in Helisoma.

# publications[].label
Serotonin-induced modulation of excitability in an identified Helisoma trivolvis neuron.

# researcherOn[].label
NSF Graduate Research Fellowship Program

# researcherOn[].awardedBy.label
National Science Foundation - (Arlington, Virginia, United States)

# researcherOn[].label
Graduate Research Fellowship Program (GRFP)

# researcherOn[].awardedBy.label
National Science Foundation - (Arlington, Virginia, United States)

# streetAddress
Texas A&M University; Biology; 3258 TAMU

# organizations[]
Office of the Provost and Executive Vice President

# etdChairOf[].label
Venkataraman, Archana (2013-05). Differential Protein Expression in the Insular Cortex and the Amygdala after Taste Memory Acquisition and Retrieval. Master's Thesis.

# etdChairOf[].label
Camacho, Alejandra Catalina (2016-08). The Role of P2X7 Receptor Signaling in Regulation of Rhythmic Astrocyte Physiology in Mouse Suprachiasmatic Nucleus Cells. Master's Thesis.

# etdChairOf[].label
Martinez, Veronica Giselle (2003-05). Cellular and molecular correlates of neural morphallaxis in Lumbriculus variegatus. Doctoral Dissertation.

# etdChairOf[].label
Cox, Kimberly Yvonne (2007-12). Melatonin modulates intercellular communication among immortalized rat suprachiasmatic nucleus cells. Master's Thesis.

# etdChairOf[].label
Richardson, Jarret Keith (2013-08). Transient Mixed Synapses Regulate Emerging Connectivity in Simple Neuronal Networks. Doctoral Dissertation.

# etdChairOf[].label
Haddix, Seth Gregory (2019-12). Mammalian Models of Duchenne Muscular Dystrophy: An Investigation on the Neuromuscular Junction and Cardiac Functionality. Doctoral Dissertation.

# etdChairOf[].label
Wright, Tyler T. (2006-12). Suppression of manganese-dependent production of nitric oxide in astrocytes: implications for therapeutic modulation of glial-derived inflammatory mediators. Master's Thesis.

# etdChairOf[].label
Triff, Karen (2016-05). Assessment of Histone Tail Modifications and Transcriptional Profiling during Colon Cancer Progression: Effect of Chemoprotective Natural Compounds. Doctoral Dissertation.

# etdChairOf[].label
Neunuebel, Joshua Paul (2004-08). Visualization of cellular mechanisms regulating differential neuronal synapse formation. Master's Thesis.

# etdChairOf[].label
Womac, Alisa Diane (2012-08). Regulation and Synchronization of the  Master Circadian Clock by Purinergic Signaling  from Suprachiasmatic Nucleus Astrocytes. Doctoral Dissertation.

# etdChairOf[].label
Burkeen, Jeffrey Franklin (2009-08). Calcium Signaling Mechanisms Mediate Clock-Controlled ATP Gliotransmission among Immortalized Rat SCN2.2 Cell Cultures. Master's Thesis.

# etdChairOf[].label
Lybrand, Zane (2012-08). Plasticity in the Rapid Escape Reflex of the Annelid Worm, Lumbriculus variegatus. Doctoral Dissertation.