Speaker: Sam Li, Department of Biochemistry and Biophysics, University of California, San Francisco

Time: 10:30 a.m., April 12, 2024, GMT+8

Venue: B117, Research Complex #2, PKU

Abstract: 

The cilium, comprising the basal body and axoneme, is a microtubule-based organelle essential for diverse cellular functions. Its assembly is intricately regulated, and mutations incilium components or disruptions in its formation can lead to various human diseases, including cancers and ciliopathies. By using electron cryo-tomography and subtomogram averaging techniques on the basal body and axoneme from the unicellular model organism Tetrahymena thermophila, we have obtained high-resolution structures of the inner junction across different regions of the cilium. Through molecular modelling, we have identified several basal body proteins, with some having distribution throughout the organelle, while others are confined to specific cilium locales. Notably, microtubule and its associated proteins are able to accommodate this composition variation, forming intricate interaction networks, bolstering the stability and robustness of the local structure. These revelations provide a molecular blueprint for understanding ciliary inner junction assembly, underscoring its precise spatiotemporal regulation.

Source: School of Life Sciences, PKU