Research Overview
Brain asymmetric patterning and neural stem cell development, Email: tas2009@med.cornell.edu
Please visit Dr. Sun's Lab Web Site
The human cortex, formed largely during embryonic development, is organized into distinct functional regions controlling complex behaviors. Accurate cytoarchitecture and precise function of the cortex depends on the production of multipotent and self-renewing neural stem cells (or progenitors) and the interconnection of specific cell types derived from them during development. Interestingly, many human mental disorders and neurodegenerative diseases are associated with anatomical disruptions of specific cortical regions. The research in my lab will address three broad and essential questions: 1. How is distinct function consistently and asymmetrically localized in one hemisphere of the human cortex? 2. How do neural stem cells self-maintain and then differentiate into distinct cell fates at the right time and the right location in order to establish complex brain anatomy and function? 3. What are the molecular mechanisms regulating development of neural circuits in the cortex?Using Serial Analysis of Gene Expression (SAGE), we have comprehensively measured gene expression levels between the left and right human fetal hemispheres and have identified some differentially expressed genes. Among them, we have found that expression of the transcription factor Lmo4 is asymmetric in human and mouse cortices. We are now studying Lmo4 function in asymmetric patterning in the cortex by establishing transgenic mouse models using gain-of-function and loss-of-function approaches. To study how functional regions arise from neural stem cells in the developing cerebral cortex, we are trying to identify differentially expressed genes in neural stem cells within three cortical regions (motor, somatosensory and visual cortex) using cDNA Microarrays. Once these region-specific markers are identified, we will first generate genetically engineered mouse models to study the function of these candidate genes. We will further study the outcomes of disrupted neural stem cell development and cortical regionalization by testing cortical circuitry and behaviors of viable mutant mouse models. For more information, contact Dr Tao Sun at tas2009@med.cornell.edu
