Movie
Controller
Structure viewers
About Yorodumi Papers
+Search query
-Structure paper
| Title | A ternary complex of MIPs in the A-tubule of basal bodies and axonemes depends on RIB22 and the EF-hand domain of RIB72A in cilia. |
|---|---|
| Journal, issue, pages | Mol Biol Cell, Vol. 36, Issue 4, Page br13, Year 2025 |
| Publish date | Apr 1, 2025 |
 Authors | Rachel A Howard-Till / Sam Li / Usha Pallabi Kar / Christopher N Fuentes / Amy S Fabritius / Mark Winey /  |
| PubMed Abstract | The lumens of the highly stable microtubules that make up the core of basal bodies, cilia, and flagella are coated with a network of proteins known as MIPs, or microtubule inner proteins. MIPs are ...The lumens of the highly stable microtubules that make up the core of basal bodies, cilia, and flagella are coated with a network of proteins known as MIPs, or microtubule inner proteins. MIPs are hypothesized to enhance the rigidity and stability of these microtubules, but how they assemble and contribute to cilia function is poorly understood. Here we describe a ciliate specific MIP, RIB22, in . RIB22 is a calmodulin-like protein found in the A-tubule of doublet and triplet microtubules in cilia and basal bodies. Its localization is dependent on the conserved MIP RIB72. Here we use cryogenic electron tomography (cryoET) to examine RIB22 and its interacting partners in axonemes and basal bodies. RIB22 forms a ternary complex with the C-terminal EF-hand domain of RIB72A and another MIP, FAM166A. strains lacking RIB22 or the EF-hand domain of RIB72A showed impaired cilia function. CryoET on axonemes from these strains demonstrated an interdependence of the three proteins for stabilization within the structure. Deletion of the RIB72A EF-hand domain resulted in the apparent loss of multiple MIPs in the region. These findings emphasize the intricacy of the MIP network and the importance of understanding MIPs' functions during cilium assembly and regulation. |
 External links | Mol Biol Cell / PubMed:39937672 / PubMed Central |
| Methods | EM (subtomogram averaging) |
| Resolution | 6.24 - 12.7 Å |
| Structure data |  EMDB-48292: Structure of axonemal DMT from wildtype Tetrahymena thermophila, centered on the A-tubule RIB22 in 16nm repeat  EMDB-48293: Structure of axonemal DMT from Tetrahymena thermophila RIB22KO mutant, centered on the A-tubule RIB72A/B in 16-nm repeat  EMDB-48294: Structure of axonemal DMT from Tetrahymena thermophila RIB72A/Delta_EF-hand mutant, centered on the A-tubule RIB72A/B in 16-nm repeat  EMDB-48295: Structure of axonemal DMT from Tetrahymena thermophila wildtype, centered on the A-tubule RIB22 in 48-nm repeat  EMDB-48296: Structure of axonemal DMT from Tetrahymena thermophila RIB72A/Delta_EF-hand mutant, centered on the A-tubule RIB72A/B in 48-nm repeat  EMDB-48297: Structure of triplet MT from the proximal region of the basal body isolated from the wildtype of Tetrahymena thermophila, centered on the A-tubule RIB22 in 16-nm repeat  EMDB-48298: Structure of triplet MT from the core region of basal body isolated from the wildtype of Tetrahymena thermophila, centered on the A-tubule RIB22 in 16-nm repeat  EMDB-48299: Structure of triplet MT from the core region of basal body isolated from the wildtype of Tetrahymena thermophila, centered on the A-tubule RIB22 in 48-nm repeat |
| Source |
|
Tetrahymena thermophila (eukaryote)