Coupling of transcription to mRNA export

• Applicant: Professorin Dr. Katja Sträßer
• Subject Area: Cell Biology
• Term: from 2004 to 2007
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 5419818

In a eukaryotic cell, mRNA export from the nucleus to the cytoplasm is essential for gene expression. In the past couple of years, our understanding of the intranuclear events of mRNA export has increased immensely. I was able to contribute to the current model by demonstrating that mRNA export through the nuclear pore complexes is functionally and physically coupled to the process of transcription elongation (Sträßer et al. (2000), JCB; Sträßer and Hurt (2000), EMBO J; Sträßer and Hurt (2001), Nature; Sträßer et al. (2002), Nature). This coupling is mediated by a protein complex named TREX, which consists of proteins with roles in transcription elongation and mRNA export. A subcomplex of TREX, the THO complex, functions in transcription elongation and is present on actively transcribed genes. During the course of the proposed project, I will focus on the coupling between transcription and mRNA export. Specifically, I want to identify components that mediate the interaction of the THO complex with the transcription machinery during elongation by biochemical and genetic approaches. I will address how THO is recruited to an actively transcribed gene and how transcription initiation is coupled to mRNA export. In addition, I will characterize the function of Gbp2, Hrb1, and Tex1, three proteins of the TREX complex about which very little is known. I expect that the results from these proposed studies will significantly advance our understanding of the processes that couple very early events in mRNA biogenesis to its export to the cytoplasm.

• DFG Programme: Research Grants