This special issue will contain 31 articles featuring research from the CECB and NIH chromatin groups.
Understanding chromosome structure and function is one of the central issues of
modern biology. Chromatin is a specialized structure in eukaryotes which packages, protects
and regulates accessibility of nuclear DNA. Vince Allfrey proposed almost fifty years ago
(Science 144: 559, 1964) that chromatin structural modifications, particularly acetylation of
histone tails, could also play a significant role in the regulation of transcription. This concept
was largely discounted for two decades, until several developments in the late 1980's focused
new attention on structural changes in chromatin.
Scientists in the NIH intramural program provided a number of key contributions to this
evolving view of chromatin and gene regulation. Gary Felsenfeld, with D. Camerini-Otero and
B. Sollner-Webb, showed that the H3/H4 tetramer forms the kernel of the nucleosome.
Felsenfeld also discovered GATA-1, a protein now seen as important in chromatin interactions.
Bob Simpson and colleagues first showed that a nucleosome could occupy selective positions on
the DNA template, and also discovered that DNA could be reconstituted onto a cross-linked
octamer, proving that the histone subunits were not intertwined with DNA. G. Hager and
colleagues demonstrated a direct role for nucleosome reorganization in gene regulation by
steroid receptors, and later discovered the rapid dynamics of protein movement during these
remodeling processes. Carl Wu isolated the first ATP-dependent chromatin remodeling
systems, presaging the characterization of this important family of enzymes.
This rich tradition of chromatin research continues on the NIH campuses. In the
National Cancer Institute, the Center of Excellence in Chromosome Biology helps to nurture
support for research and postdoctoral training in the chromatin/chromosome field. The CECB
center has recently joined forces with the NIH wide chromatin interest group to foster
increased communication and interaction with the international community.
The reviews in this issue reflect the breath of activities ongoing within the NIH
intramural program. Areas discussed include chromatin domains, chromatin boundaries and
insulators, chromosomal proteins, epigenetic modification of chromatin proteins, DNA damage
in the chromatin context, chromatin dynamics and oscillatory mechanisms, specialized
chromosome structures, DNA topology, and other current issues in chromosome biology. We
are in a golden age of discovery in the field. The increased understanding of mechanisms
involved in chromosome function will continue to provide unexpected opportunities in the
realm of human health.
Gordon L. Hager
Chair, Center of Excellence in Chromosome Biology, CCR, NCI
Lab of Receptor Biology and Gene Expression, CCR, NCI
Congratulations to Dan Larson, receipent of the 2012 Presidential Early Career Award for Scientists and Engineers for his studies on transcription dynamics of single human genes. The PECASE award is the highest honor bestowed by the United States Government on science and engineering professionals in the early stages of their independent research careers.
Tom Misteli received the Arthur S. Flemming Award for his work in cancer cell biology that has led to several important conceptual advances in the fundamental understanding of genome function and that has practical application in biomedicine.