Genetics and Gene Regulation Program

Address

Rosenthal Building Room 146
3800 Spruce St
Philadelphia, PA 19104-6049

Office tel.: 215 898-0454
Lab tel.: 215 898-0907
Fax: 215 573-5189
E-mail: pehrson@vet.upenn.edu

EDUCATION

University of Washington, B.S. (Chemistry) 1976

University of California, Berkeley, PhD (Biochemistry) 1981

RESEARCH INTERESTS

• Role of histone variants in regulating chromatin structure and function

Key words: Histone variants, chromatin, macroH2A, inactive X chromosome, gene regulation..

Search PubMed for articles

DESCRIPTION OF RESEARCH

Currently we are studying a novel group of core histone proteins that we discovered in rat liver nucleosomes. These proteins are three times the size of conventional core histones, and have a hybrid structure consisting of a large nonhistone region and a region that closely resembles a conventional histone H2A. We call these proteins macroH2A, and currently know of three macroH2A subtypes. Recently we showed that macroH2A proteins are preferentially concentrated in the transcriptionally inactive X chromosome of female mammals. MacroH2A is also concentrated in specific chromatin domains other than the inactive X chromosome. Some of these non-X domains are composed of heterochromatin, and therefore, also appear to be transcriptionally silent. Thus, macroH2A may be involved in establishing or maintaining specific domains of transcriptionally silent chromatin. Our current projects include studies to examine macroH2A function in vivo, the effects of macroH2A on nucleosomal and higher chromatin structures, and the mechanisms involved in localizing macroH2A to specific

RECENT PUBLICATIONS

Beletskii, A., Hong, Y.-K., Pehrson, J., Egholm, M. and Strauss, W.M.
PNA interference mapping demonstrates functional domains in the
noncoding RNA Xist. Proc. Natl. Acad. Sci USA 98, 9215-9220, 2001.

Rasmussen, T.P., Wutz, A., Pehrson, J.R. and Jaenisch, R. Expression
of Xist RNA is sufficient to initiate macrochromatin body formation.
Chromosoma, 110, 411-420, 2001.

Nesterova T.B., Mermoud J.E., Hilton, K., Pehrson, J., Surani, A.M.,
McLaren, A. and Brockdorff, N. Xist expression and macroH2A1.2
localisation in mouse primordial and pluripotent embryonic germ
cells. Differentiation 69, 216-225, 2002.

Pehrson, J.R. and Changolkar, L.N. Reconstitution of nucleosomes with
histone macroH2A1.2. Biochemistry, 41, 179-184, 2002.

Turner, J.M.A., Mahadevaiah, S.K., Elliott, D.J., Garchon, H.-J.,
Pehrson, J.R. and Jaenisch, R., Burgoyne, P.S. Meiotic sex chromosome
inactivation in male mice with targeted disruptions of Xist. J. Cell
Sci. 115, 4097-4105, 2002.

Lab

ROTATION PROJECTS

Please see Dr Pehrson.

Lab personnel:

Carl Costanzi, PhD, Senior Research Investigator
Lakshmi N. Changolkar, M.S., Research Specialist
Dannee Z. Chen, B.S., Research Specialist
Adrian N. Leu, B.S. Research Specialist