Structural highlights
Function
TBA1B_PIG Tubulin is the major constituent of microtubules. It binds two moles of GTP, one at an exchangeable site on the beta chain and one at a non-exchangeable site on the alpha chain.
Publication Abstract from PubMed
Microtubule (MT)-associated protein 7 (MAP7) is a required cofactor for kinesin-1-driven transport of intracellular cargoes. Using cryo-electron microscopy and single-molecule imaging, we investigated how MAP7 binds MTs and facilitates kinesin-1 motility. The MT-binding domain (MTBD) of MAP7 bound MTs as an extended alpha helix between the protofilament ridge and the site of lateral contact. Unexpectedly, the MTBD partially overlapped with the binding site of kinesin-1 and inhibited its motility. However, by tethering kinesin-1 to the MT, the projection domain of MAP7 prevented dissociation of the motor and facilitated its binding to available neighboring sites. The inhibitory effect of the MTBD dominated as MTs became saturated with MAP7. Our results reveal biphasic regulation of kinesin-1 by MAP7 in the context of their competitive binding to MTs.
Structural and functional insight into regulation of kinesin-1 by microtubule-associated protein MAP7.,Ferro LS, Fang Q, Eshun-Wilson L, Fernandes J, Jack A, Farrell DP, Golcuk M, Huijben T, Costa K, Gur M, DiMaio F, Nogales E, Yildiz A Science. 2022 Jan 21;375(6578):326-331. doi: 10.1126/science.abf6154. Epub 2022 , Jan 20. PMID:35050657[1]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
References
- ↑ Ferro LS, Fang Q, Eshun-Wilson L, Fernandes J, Jack A, Farrell DP, Golcuk M, Huijben T, Costa K, Gur M, DiMaio F, Nogales E, Yildiz A. Structural and functional insight into regulation of kinesin-1 by microtubule-associated protein MAP7. Science. 2022 Jan 21;375(6578):326-331. doi: 10.1126/science.abf6154. Epub 2022 , Jan 20. PMID:35050657 doi:http://dx.doi.org/10.1126/science.abf6154
