|
lab profile
|
Chris Rose James Madison University MSC 7801
Biology
Harrisonburg, VA 22802
USA
rosecs@jmu.edu 540-568-6666
|
PI: |
YES |
Taxa Studied: |
Vertebrate Animals |
Techniques Employed: |
In Situ Hybridization, Antibody Staining, Sectioning for Histology, Scanning Electron Microscopy, Epifluoresence Microscopy, Confocal Microscopy |
Research Description: |
My research is generally on the development and evolution of amphibians, and specifically on the growth, metamorphosis, and evolution of their skeletal morphology. One project addresses the role of cell behaviors in the growth and metamorphic remodeling of cranial cartilages. Amphibians differ from most vertebrates in having pharyngeal arch cartilages that grow isometrically and then undergo different kinds of change shape at metamorphosis. Cell behaviors that might contribute to growth and shape change in cartilage include cell division, cell growth, change in cell shape, cell death, cell apposition, and matrix secretion. The cell behaviors underlying shape change might be either regionalized or interspersed within cartilages. Our work focuses on two cartilages, Meckels cartilage of the lower jaw and the ceratohyal, that are not replaced by bone and lack any evidence of regionalized cell behaviors at larval stages. We produce and compare spatial maps of different cell behaviors and properties for each cartilage at various larval and metamorphic stages to better understand how cell division, cell growth, and cell apposition contribute to isometric growth, how metamorphic cell behaviors are patterned inside larval cartilages, and how cell behaviors change in the two transitions between growth and shape change. A second project uses linear dimensions and several landmark- and curved-based morphometric techniques to analyze the pattern of shape change in pharyngeal arch cartilages during growth and metamorphosis. Other research uses neural crest transplant and ectopic gene expression techniques to test whether the embryonic expression of Hox genes that control the specification of the larval shape of these cartilages is also involved in specifying their response to thyroid hormone in metamorphic remodeling. While the studies on describing cartilage shape and patterns of cell behavior are currently limited to Xenopus laevis, the ultimate goal is to develop a methodological framework for comparative studies that will address the role of cell behaviors and their mediation by thyroid hormone in the evolutionary diversification of amphibian skeleton. My research techniques include osteological and morphometric analyses, all kinds of microscopy, in situ hybridization, immunohistochemistry, tissue grafting and mRNA injections of embryos. |
Lab Web Page: |
http://www.jmu.edu/biology/faculty_rose.shtml |
Willing to Host Undergraduates: |
YES |
Actively Seeking Undergraduates: |
YES |
|
|