Structural highlights
Function
RSSA1_YEAST Required for the assembly and/or stability of the 40S ribosomal subunit. Required for the processing of the 20S rRNA-precursor to mature 18S rRNA in a late step of the maturation of 40S ribosomal subunits.[1] [2]
Publication Abstract from PubMed
The essential ATP-binding cassette protein ABCE1 splits 80S ribosomes into 60S and 40S subunits after canonical termination or quality-control-based mRNA surveillance processes. However, the underlying splitting mechanism remains enigmatic. Here, we present a cryo-EM structure of the yeast 40S-ABCE1 post-splitting complex at 3.9-A resolution. Compared to the pre-splitting state, we observe repositioning of ABCE1's iron-sulfur cluster domain, which rotates 150 degrees into a binding pocket on the 40S subunit. This repositioning explains a newly observed anti-association activity of ABCE1. Notably, the movement implies a collision with A-site factors, thus explaining the splitting mechanism. Disruption of key interactions in the post-splitting complex impairs cellular homeostasis. Additionally, the structure of a native post-splitting complex reveals ABCE1 to be part of the 43S initiation complex, suggesting a coordination of termination, recycling, and initiation.
Structure of the 40S-ABCE1 post-splitting complex in ribosome recycling and translation initiation.,Heuer A, Gerovac M, Schmidt C, Trowitzsch S, Preis A, Kotter P, Berninghausen O, Becker T, Beckmann R, Tampe R Nat Struct Mol Biol. 2017 Apr 3. doi: 10.1038/nsmb.3396. PMID:28368393[3]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
References
- ↑ Ford CL, Randal-Whitis L, Ellis SR. Yeast proteins related to the p40/laminin receptor precursor are required for 20S ribosomal RNA processing and the maturation of 40S ribosomal subunits. Cancer Res. 1999 Feb 1;59(3):704-10. PMID:9973221
- ↑ Tabb-Massey A, Caffrey JM, Logsden P, Taylor S, Trent JO, Ellis SR. Ribosomal proteins Rps0 and Rps21 of Saccharomyces cerevisiae have overlapping functions in the maturation of the 3' end of 18S rRNA. Nucleic Acids Res. 2003 Dec 1;31(23):6798-805. PMID:14627813
- ↑ Heuer A, Gerovac M, Schmidt C, Trowitzsch S, Preis A, Kotter P, Berninghausen O, Becker T, Beckmann R, Tampe R. Structure of the 40S-ABCE1 post-splitting complex in ribosome recycling and translation initiation. Nat Struct Mol Biol. 2017 Apr 3. doi: 10.1038/nsmb.3396. PMID:28368393 doi:http://dx.doi.org/10.1038/nsmb.3396
