Marcia G. Honig, Ph.D.
Department of Anatomy and Neurobiology
The University of Tennessee Health Science Center
855 Monroe Avenue, Suite 515
Memphis, TN 38163
Phone: (901) 448-5998
Fax: (901) 448-7193
Lab: 534 Johnson Building
Email: Marcia G. Honig
- Ph.D. Institution: Yale University, Department of Biology
- Postdoctoral: State University of New York at Stony Brook, Department of Neurobiology and Behavior; University of Michigan, Department of Biology
My research is focused on understanding how neurons establish appropriate connections during development. As part of our previous work focusing on somatosensory neurons and using chick embryos as a model system, we identified the chicken homolog of cerebellin (Cbln) 2. Cblns are a family of four secreted proteins that, despite their name, are widely expressed in the nervous system and have been shown to promote synapse formation. In accord with this, we found that Cbln2 is expressed by specific subsets of neurons in the sensory ganglia and by neurons located in regions of the spinal cord where those sensory neurons project. To study Cbln function, we have transitioned to using mice as our experimental system because of the wealth of available genetic resources. Characterization of the distribution of Cblns1, 2, and 4 in the mouse spinal cord has demonstrated that each Cbln is expressed by discrete populations of neurons in the dorsal horn. To investigate the role of Cblns in the formation of sensory neuron synapses in the dorsal horn, we plan to examine how synaptic connections formed by specific kinds of sensory afferents with their targets in the dorsal horn are altered in Cbln1-null and Cbln2-null mice, through a collaboration with Jim Morgan at St Jude's who has generated a variety of such knockout mice.
We are also currently developing a novel mouse model of mild-to-moderate spinal cord injury. This work uses an air blast cannon system (i.e. a modified paintball gun) that was designed to induce a non-invasive percussive injury. Our goal is to produce diffuse axonal injury, such as would occur when the spinal cord is stretched or deformed but the vertebral column remains intact, and thereby to mimic the damagethat frequently accompanies motor vehicle accidents, falls, and sports injuries. The injury is being evaluated using both behavioral assays and immunofluorescent labeling to reveal effects on specific neuronal tracts. Future studies will elucidate the cellular and molecular mechanisms underlying the injury and assess possible therapies.
- Heldt SA, Elberger AJ, Deng Y, Guley NH, Del Mar N, Rogers J, Choi GW, Ferrell J, Rex TS, Honig MG, Reiner A. A novel closed-head model of mild traumatic brain injury caused by primary overpressure blast to the cranium produces sustained emotional deficits in mice. Front Neurol. 2014 Jan 22;5:2. doi: 10.3389/fneur.2014.00002. eCollection 2014. PubMed PMID: 24478749; PubMed Central PMCID: PMC3898331.
- Cagle MC, Honig MG. Parcellation of cerebellins 1, 2, and 4 among different subpopulations of dorsal horn neurons in mouse spinal cord. J Comp Neurol. 2014 Feb 1;522(2):479-97. doi: 10.1002/cne.23422. PubMed PMID: 23853053; PubMed Central PMCID: PMC3855892.
- Reiner A, Yang M, Cagle MC, Honig MG. Localization of cerebellin-2 in late embryonic chicken brain: implications for a role in synapse formation and for brain evolution. J Comp Neurol. 2011 Aug 1;519(11):2225-51. doi: 10.1002/cne.22626. PubMed PMID: 21456003; PubMed Central PMCID: PMC3392029.
- Yang M, Cagle MC, Honig MG. Identification of cerebellin2 in chick and its preferential expression by subsets of developing sensory neurons and their targets in the dorsal horn. J Comp Neurol. 2010 Jul 15;518(14):2818-40. doi: 10.1002/cne.22366. PubMed PMID: 20506477; PubMed Central PMCID: PMC2880495.
- Honig MG, Camilli SJ, Surineni KM, Knight BK, Hardin HM. The contributions of BMP4, positive guidance cues, and repulsive molecules to cutaneous nerve formation in the chick hindlimb. Dev Biol. 2005 Jun 1;282(1):257-73. PubMed PMID: 15936345.
- Honig MG, Camilli SJ, Xue QS. Ectoderm removal prevents cutaneous nerve formation and perturbs sensory axon growth in the chick hindlimb. Dev Biol. 2004 Feb 1;266(1):27-42. PubMed PMID: 14729476.