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bioRxiv · 10.1101/2023.06.23.546279

Cross-linking mass spectrometric analysis of the endogenous TREX complex from S. cerevisiae

Kern, C.·Radon, C.·Wende, W.·Leitner, A.·Straesser, K.
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Abstract

The conserved TREX complex has multiple functions in gene expression such as transcription elongation, 3 end processing, mRNP assembly and nuclear mRNA export as well as the maintenance of genomic stability. In S. cerevisiae, TREX is composed of the pentameric THO complex, the DEAD-box RNA helicase Sub2, the nuclear mRNA export adaptor Yra1 and the SR-like proteins Gbp2 and Hrb1. Here, we present the structural analysis of the endogenous TREX complex of S. cerevisiae purified from its native environment. To this end, we used cross-linking mass spectrometry to gain structural information on regions of the complex that are not accessible to classical structural biology techniques. We also used negative-stain electron microscopy to investigate the organization of the cross-linked complex used for XL-MS by comparing our endogenous TREX complex with recently published structural models of recombinant THO-Sub2 complexes. According to our analysis, the endogenous yeast TREX complex preferentially assembles into a dimer. The overall structures of the recombinant yeast THO-Sub2 complexes strongly resemble the structural conformation of the monomers and the dimer interface of the endogenous TREX complex.

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Kern, C., Radon, C., Wende, W., Leitner, A., Straesser, K.. 2023-06-23. Cross-linking mass spectrometric analysis of the endogenous TREX complex from S. cerevisiae. https://doi.org/10.1101/2023.06.23.546279

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