Integrative modeling reveals the molecular architecture of the intraflagellar transport A (IFT-A) complex
Abstract
Intraflagellar transport (IFT) is a conserved process of cargo transport in cilia that is essential for development and homeostasis in organisms ranging from algae to vertebrates. In humans, variants in genes encoding subunits of the cargo-adapting IFT-A and IFT-B protein complexes are a common cause of genetic diseases known as ciliopathies. While recent progress has been made in determining the atomic structure of IFT-B, little is known of the structural biology of IFT-A. Here, we combined chemical cross-linking mass spectrometry and cryo-electron tomography with AlphaFold2-based prediction of both protein structures and interaction interfaces to model the overall architecture of the monomeric six-subunit IFT-A complex, as well as its polymeric assembly within cilia. We define monomer-monomer contacts and membrane-associated regions available for association with transported cargo, and we also use this model to provide insights into the pleiotropic nature of human ciliopathy-associated genetic variants in genes encoding IFT-A subunits. Our work demonstrates the power of integration of experimental and computational strategies both for multi-protein structure determination and for understanding the etiology of human genetic disease.
Document Details
- Document Type
- Pub Defense Publication
- Publication Date
- Nov 08, 2022
- Source ID
- 10.7554/elife.81977
Entities
People
- Caitlyn L McCafferty
- Candice Nichols
- David W Taylor
- Edward Marcotte
- Gabriel Hoogerbrugge
- Gaia Pigino
- John B. Wallingford
- Mareike A. Jordan
- Ophelia Papoulas
Organizations
- Army Research Office
- Cancer Prevention and Research Institute of Texas
- Eunice Kennedy Shriver National Institute of Child Health and Human Development
- Human Technopole Foundation
- Max Planck Institute of Molecular Cell Biology and Genetics
- Max Planck Society
- National Institute of General Medical Sciences
- National Science Foundation
- Robert A. Welch Foundation
- University of Texas at Austin