James I. Morgan, Ph.D.
Member and Chair
Department of Developmental Neurobiology
Shahdam, Edna and Albert Abdo Basic Science Chair
St. Jude Children's Research Hospital
Department of Anatomy and Neurobiology
St. Jude Children's Research Hospital
MS 323, Room D2025E
262 Danny Thomas Place
Memphis, TN 38105-3678
Phone: (901) 595-2256
Fax: (901) 595-3143
Email: James I. Morgan
- Ph.D. Institution: University of Aston, Birmingham, England
- Postdoctoral: Max Planck Institute, Tubingen, Germany
Research in this laboratory is aimed at providing an understanding of the molecular mechanisms that contribute to normal and pathological neuronal death and differentiation. In adult and developing animals, nerve cells and their precursors are confronted with a series of decisions involving choices such as exiting the cell cycle, undergoing apoptosis or differentiation, migrating and establishing, maintaining and modifying their correct synaptic connections. Perturbations in these processes have profound consequences and result in a wide range of pathological outcomes such as brain tumors, epilepsy, mental retardation, Parkinson's and Alzheimer's diseases. We employ the tools of contemporary molecular biology, genomics and cellular imaging in models of aberrant neuronal death and differentiation to identify the genes that play critical roles in these processes. The products of these genes and the pathways in which they function become targets for novel therapeutic strategies aimed at preventing or ameliorating human diseases of the nervous system.
Current research in the laboratory focuses upon investigating genes and signaling pathways that contribute to: (1) neuronal death (Nna1), (2) synaptic stability (Cbln1) and (3) tumor formation (Ptch) in the developing cerebellum. Nna1 is the defective gene in the Purkinje cell degeneration (pcd) cerebellar mutant, and encodes a novel intracellular zinc carboxypeptidase. Nna1 is also induced in regenerating neurons placing it at the intersection between neuron degeneration and regeneration. Cbln1 is the prototype of a family of secreted TNF-related proteins (the synaptotrophins) that regulate synaptic stability and neuronal survival in developing cerebellum. Ptch is the receptor for sonic hedgehog and disruption of its signaling in cerebellar granule neuron precursors leads to the pediatric brain tumor, medulloblastoma.
- Morgan JI, Harris PR. Evidence that brief self-affirming implementation intentions can reduce work-related anxiety in downsize survivors. Anxiety Stress Coping. 2015 Feb 4:1-13. [Epub ahead of print] PubMed PMID: 25575334.
- Wu HY, Rong Y, Correia K, Min J, Morgan JI. Comparison of the enzymatic and functional properties of three cytosolic carboxypeptidase family members. J Biol Chem. 2015 Jan 9;290(2):1222-32. doi: 10.1074/jbc.M114.604850. Epub 2014 Nov 21. PubMed PMID: 25416787; PubMed Central PMCID: PMC4294487.
- Wu HY, Wang T, Li L, Correia K, Morgan JI. A structural and functional analysis of Nna1 in Purkinje cell degeneration (pcd) mice. FASEB J. 2012 Nov;26(11):4468-80. doi: 10.1096/fj.12-205047. Epub 2012 Jul 26. PubMed PMID: 22835831; PubMed Central PMCID: PMC3475255.
- Morgan JI, Jones FA, Harris PR. Direct and indirect effects of mood on risk decision making in safety-critical workers. Accid Anal Prev. 2013 Jan;50:472-82. doi: 10.1016/j.aap.2012.05.026. Epub 2012 Jun 26. PubMed PMID: 22742773.
- Pattarini R, Rong Y, Shepherd KR, Jiao Y, Qu C, Smeyne RJ, Morgan JI. Long-lasting transcriptional refractoriness triggered by a single exposure to 1-methyl-4-phenyl-1,2,3,6-tetrahydropyrimidine. Neuroscience. 2012 Jul 12;214:84-105. doi: 10.1016/j.neuroscience.2012.03.047. Epub 2012 Apr 24. PubMed PMID: 22542874; PubMed Central PMCID: PMC3371097.
- Morgan MA, Morgan JI. Pcp4l1 contains an auto-inhibitory element that prevents its IQ motif from binding to calmodulin. J Neurochem. 2012 Jun;121(6):843-51. doi: 10.1111/j.1471-4159.2012.07745.x. Epub 2012 Apr 27. PubMed PMID: 22458599; PubMed Central PMCID: PMC3371134.