MRNA recognition and packaging by the human transcription-export complex.

ABSTRACT: Newly made mRNAs are processed and packaged into mature ribonucleoprotein complexes (mRNPs) and are recognized by the essential transcription-export complex (TREX) for nuclear export^1,2. However, the mechanisms of mRNP recognition and three-dimensional mRNP organization are poorly understood³. Here we report cryo-electron microscopy and tomography structures of reconstituted and endogenous human mRNPs bound to the 2-MDa TREX complex. We show that mRNPs are recognized through multivalent interactions between the TREX subunit ALYREF and mRNP-bound exon junction complexes. Exon junction complexes can multimerize through ALYREF, which suggests a mechanism for mRNP organization. Endogenous mRNPs form compact globules that are coated by multiple TREX complexes. These result

SUBMITTER: Pacheco-Fiallos B 

PROVIDER: S-EPMC7614608 | biostudies-literature | 2023 Apr

REPOSITORIES: biostudies-literature