Lab introduction
Welcome to the Dernburg lab! We are part of the Lawrence Berkeley National Labs Life Sciences division as well as the UC Berkeley Molecular and Cell Biology program.
Our lab
is interested in meiosis, the special division process by which the genetic information on
chromosomes is transmitted from parent to progeny through sexual reproduction. Errors in this process lead to aneuploidy and
are a major cause of human birth defects such as Down syndrome. We are investigating how chromosomes are reorganized during this unique cell cycle by combining
high-resolution imaging of chromosomes in situ and in vivo with the molecular genetic advantages
of C. elegans. A fundamental goal of our work is to understand how specific DNA sequences confer
not only gene expression patterns but also the large-scale 3-dimensional organization of the genome.
Project #1: Dissecting the function of meiotic pairing centers
When most people think of
genomics, they often consider only the portion of the genome containing protein coding and
expression information. My group is interested how information encoded within the genome controls
global chromosome architecture and mediates interactions between chromosomes and other components
of the cellular machinery. In all eukaryotes, simple, repetitive sequence elements play major
roles in chromosome structure and inheritance functions. For example, work in a variety of
organisms has elucidated the behavior of centromeres and telomeres, two types of sites containing
noncoding sequences with fundamental roles in chromosome organization and function. We are
exploring the function of another type of cisacting site that is much more poorly understood:
meiotic pairing centers. In C. elegans, these specific sites on each of the six chromosomes
are
essential for meiotic recombination and accurate segregation.
New tools for understanding noncoding DNA sequences have become available through
genome
sequencing efforts. C. elegans is unusual in that its genome assemblies now include
virtually all
of the so-called "junk DNA" - the simple-sequence repetitive elements, or heterochromatin. Through
bioinformatics, we have identified a unique repetitive element whose genomic distribution
corresponds precisely with the location of meiotic pairing centers, and we are currently testing
whether this sequence can mediate homologous interactions during meiosis. Using classical and
reverse genetics, we have also identified a number of genes that interact with the Pairing
Centers, and we are working to understand how their encoded proteins contribute to the function of
these sites.
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Project #2: Meiotic chromosome dynamics in vivo
A major goal of our lab is to
understand how the biophysical properties of chromosomes are modulated during meiosis, and how
these properties control behaviors such as homolog pairing and recombination. Because C.
elegans
is optically transparent, we can observe these dynamic events as they occur in living animals. We
have recorded large-scale chromosome movements during the stages of homolog pairing and synapsis
using high-resolution 4-dimensional imaging. We are identifying the molecules driving this
movement, and developing methods to describe these dynamics quantitatively. A key goal for the
future is to implement automated methods to extract information from complex 4-D images.
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Please notify the webmaster of any broken links, missing graphics or incorrect information. All contents copyright 2000-2006, Dernburg Research Laboratory and Lawrence Berkeley National Labs. All rights reserved. Last modified May 31, 2006. This site was designed and created by Jacqueline Chretien.