Faculty Profiles

« Return to Faculty List

Andrew S. Belmont Professor Cell and Developmental Biology and Biophysics M.D./Ph.D. 1983, Temple University Chromatin structure and nuclear architecture Andrew S. Belmont B509 CLSL, MC-123 601 S. Goodwin Ave. Urbana, IL 61801 217-244-2311 asbel@illinois.edu

Within the higher eukaryotic chromosome DNA is folded into multiple levels of organization. Together these yield greater than a 10,000:1 linear condensation of DNA. The highest levels of folding, accounting for up to a 250:1 packing ratio and involving the organization of entire transcription and replication units, are essentially uncharacterized at this time. We are focusing on changes in interphase chromosome structure during cell cycle progression and initiation of DNA replication and transcription with the goal of identifying intermediates in the pathway of chromosome condensation/decondensation. Three-dimensional reconstructions using light and electron microscopy are used to "computationally" unravel native chromosome structure. Recently we have developed an alternative method for in situ localization of specific DNA sequences using lac operator/repressor staining which provides improved ultrastructural preservation and direct in vivo observations. Using these techniques the following questions are being addressed. What structural motifs underlie chromosome architecture and how are these motifs modified during progression through interphase, and, in particular, during DNA replication? To what degree is a given DNA sequence organized in the same large-scale chromatin conformation in different cells? What changes in large-scale chromatin organization are associated with transcriptional activation?