Skip navigation

James Dahlberg

Professor of Biomolecular Chemistry

James Dahlberg
Address:
694 Medical Sciences Center
Telephone:
262-1459
Email:
dahlberg@wisc.edu
Research Fields:
Gene Expression
Genomics
Molecular Genetics

Ph.D., University of Chicago, 1966

Postdoctoral Research: MRC Cambridge, UK; Geneva

Research Interests

Mechanisms and controls of nucleocytoplasmic RNA transport

Research Description

Our research centers on the mechanisms by which RNAs and proteins are moved within nuclei of cells and between the nucleus and cytoplasm. Our goals are to understand how the transport of RNA, which is so essential to gene expression, occurs in cells and how it can be controlled. The experimental systems that we use are primarily microinjection into X. laevis oocytes, transport into nuclei of permeabilized tissue culture cells and yeast genetics (normal and two hybrid selection).

Export is used as a point at which the RNA cargos are subject to quality control, thereby reducing the amounts of immature or defective molecules that reach the cytoplasm. For example, we recently discovered that tRNAs are aminoacylated in the nucleus prior to export, as a means of proofreading, and are now studying how the state of aminoacylation affects tRNA export.

We are also studying the mechanisms responsible for RNA retention in the nucleus or export to the cytoplasm, and have discovered a powerful inhibitor of export, the matrix protein of vesicular stomatitis virus. Currently, we are using this inhibitor as a probe into intranuclear events that are prerequisites for export.

Representative Publications

  • Tam, W. and Dahlberg, J.E. 2006. miR-155/BIC as an oncogenic microRNA. Genes Chromosomes Cancer. 45:211-212. .
  • Eis, P.S., Tam, W., Sun, L., Chadburn, A., Li, Z., Gomez, M.F., Lund, E. and Dahlberg, J.E. 2005. Accumulation of miR-155 and BIC RNA in human B cell lymphomas. Proc. Natl. Acad. Sci. USA. 102:3627-3632.
  • Allawi, H.T., Dahlberg, J.E., Olson, S., Lund, E., Olson, M., Ma, W.P., Takova, T., Neri, B.P., Lyamichev, V.I. 2004. Quantitation of microRNAs using a modified Invader assay. RNA. 10:1153-1161.
  • Dahlberg, J.E. and Lund, E. 2004. Does protein synthesis occur in the nucleus? Curr Opin Cell Biol. 16:335-338. .
  • Lund, E., Guttinger, S., Calado, A., Dahlberg, J.E. and Kutay, U. 2004. Nuclear export of microRNA precursors. Science. 303:95-98. .