James R. LaFountain

Cell Biology: Mechanism of Chromosome Segregation

Professor

Ph.D 1970 University at Albany
Postdoctoral work 1971 Swiss Federal Institute of Technology, Zurich
Assistant Professor 1972;
Associate Professor 1977;
Professor 1986 University at Buffalo

Address Information

James R. LaFountain
Department of Biological Sciences
657 Cooke Hall
State University of New York at Buffalo
Buffalo, NY 14260

(716) 645-2363 ext: 162

To send e-mail: jrl@acsu.buffalo.edu

RESEARCH SUMMARY

The movement of chromosomes during meiosis is the central focus of the research conducted in my laboratory. We use crane-fly spermatocytes because they have few chromosomes – diploid complement is eight: two sex chromosomes and three pairs of autosomes – and a large spindle during meiosis I, offering an ideal system for tracking the movement of individual chromosomes as they congress and segregate during meiosis.

At present, we are concentrating our effort on the process of microtubule flux – the poleward translocation of microtubules resulting from plus end addition and minus end removal of tubulin subunits – that occurs at velocities of ~1µm/min during metaphase and anaphase in spermatocytes. We aim to better characterize the phenomenon of flux using fluorescent speckle microscopy, as well as to achieve a better understanding of the mechanism underlying it.

Micrographs of a crane-fly spermatocyte viewed with a differential interference contrast microscopy (a) and with polarized light microscopy (b and c) illustrating the birefringent spindle fibers that extend from kinetochores to the spindle poles at metaphase.

PUBLICATIONS