The lissencephaly 1 protein, LIS1, is mutated in type-1 lissencephaly and is a key regulator of cytoplasmic dynein-1. At a molecular level, current models propose that LIS1 activates dynein by relieving its autoinhibited form. Previously we reported a 3.1Å structure of yeast dynein bound to Pac1, the yeast homologue of LIS1, which revealed the details of their interactions (Gillies et al., 2022). Based on this structure, we made mutations that disrupted these interactions and showed that they were required for dynein’s function in vivo in yeast. We also used our yeast dynein-Pac1 structure to design mutations in human dynein to probe the role of LIS1 in promoting the assembly of active dynein complexes. These mutations had relatively mild effects on dynein activation, suggesting that there may be differences in how dynein and Pac1/LIS1 interact between yeast and humans. Here, we report cryo-EM structures of human dynein-LIS1 complexes. Our new structures reveal the differences between the yeast and human systems, provide a blueprint to disrupt the human dynein-LIS1 interaction more accurately, and map type-1 lissencephaly disease mutations, as well as mutations in dynein linked to malformations of cortical development/ intellectual disability, in the context of the dynein-LIS1 complex.
Cryo-EM maps and resulting models have been deposited in the EM Data Bank (maps) and PDB (models). Raw micrographs have been deposited in EMPIAR. Accession numbers are listed in Supplementary File 1.
Structures of human dynein in complex with the lissencephaly 1 protein, LIS1EM Data Bank: EMD-27783.
Structures of human dynein in complex with the lissencephaly 1 protein, LIS1EM Data Bank: EMD-27782.
Human cytoplasmic dynein bound to Lis1EMPIAR, EMPIAR-11373.
- Janice M Reimer
- Morgan E DeSantis
- Samara L Reck-Peterson
- Samara L Reck-Peterson
- Andres E Leschziner
- Andres E Leschziner
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
- Anna Akhmanova, Utrecht University, Netherlands
- Received: October 21, 2022
- Accepted: January 8, 2023
- Accepted Manuscript published: January 24, 2023 (version 1)
© 2023, Reimer et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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