John A. Trotter, PhD

Research Interests

Molecular and supramolecular structures and their interactions. Current research focuses on the composition, structure, and assembly of collagen fibrils from echinoderms, and on the molecules that interact with the surfaces of the fibrils. Echinoderms are used because of their unique capacity to regulate the mechanical properties of their collagenous tissues through neuro-secretions. They are the only group of animals that have neutrally-regulated collagenous tissues, and the only group from which native collagen fibrils similar to those in vertebrates can be isolated in abundance. Biochemical and biophysical methods are used to purify and characterize collagen fibrils, proteoglycans and glycoproteins. The purified components are analyzed by electron microscopy and other physical techniques, and in functional assays. The aim is to understand how the different macromolecules interact with collagen fibrils to modulate their interactions.

Previous projects have included: Analysis of the relationship between cell fusion and skeletal muscle differentiation; Analysis of the regulation of actin-myosin interactions in macrophages; Analysis of stress-transfer in skeletal muscle, including muscle-tendon junctions and tapered muscle fibers.

Education, Honors and Professional Experience

1969, B.A., The Johns Hopkins University
1976, Ph.D., The University of Washington, Department of Biological Structure
1976-78, Postdoctoral Studies, NHLBI, Cardiology Branch, Laboratory of Molecular Cardiology.

Selected Recent Publications

Trotter, J.A., F.A. Thurmond and T.J. Koob. (1994) Molecular structure and functional morphology of echinoderm collagen fibrils. 
Cell Tiss. Res. 275:451-458. 

Thurmond, F.A. and J.A. Trotter. (1994) Native collagen fibrils from echinoderms are molecularly bipolar. 
J. Mol. Biol. 235:73-79. 

Trotter, J.A., G. Lyons-Levy, D. Luna, T.J. Koob, D.R. Keene, and M.A. L. Atkinson. (1996) Stiparin: a glycoprotein from sea cucumber dermis that aggregates collagen fibrils. 
Matrix Biology (in press). 

Trotter, J.A., F.J.R. Richmond and P.P. Purslow. (1995) Functional morphology and motor control of series fibered muscles. 
Exer. Sp. Sci. Rev. 23:167-213. 

Kadler, K.E., D.F. Holmes, J.A. Trotter and J.A. Chapman. (1996) Collagen fibril formation. 
Biochem. J. 316:1-11. 

Thurmond, F.A., T.J. Koob, J.M. Bowness and J.A. Trotter (1997) Partial biochemical and immunologic characterization of fibrillin microfibrils from sea cucumber dermis. Connect. Tis. Res. 36:211-222. 

Trotter, J.A. and Chino, K. (1997) Regulation of cell-dependent viscosity in the dermis of the sea cucumber Actinopyga agassizi. Comp. Biochem. Physiol. 118A:805-811. 

deVente, J.E., G.E. Lester, J.A. Trotter and L.E. Dahners (1997) Isolation of intact collagen fibrils from healing ligament. 
J. Elec. Mic. 46:353-356. 

Trotter, J.A., J.A. Chapman, K.E. Kadler and D.F. Holmes (1998) Growth of sea cucumber collagen fibrils occurs at the tips and centers in a coordinated manner. 
J. Mol. Biol. 284:1417-1424.