5M9E

Interactions between the Mal3 EB1-like domain and Dis1

Summary for 5M9E

• Entry DOI: 10.2210/pdb5m9e/pdb
• Descriptor: Microtubule integrity protein mal3, Phosphoprotein p93 (2 entities in total)
• Functional Keywords: eb1 domain, microtubule-binding, coiled-coil, cell cycle
• Biological source: Schizosaccharomyces pombe 972h-; More
• Cellular location: Cytoplasm, cytoskeleton : Q10113; Cytoplasm, cytoskeleton, microtubule organizing center, spindle pole body : Q09933
• Total number of polymer chains: 8
• Total formula weight: 45315.07

Authors

Zakian, S.,Singleton, M.R. (deposition date: 2016-11-01, release date: 2016-12-07, Last modification date: 2024-01-17)

Primary citation

Matsuo, Y.,Maurer, S.P.,Yukawa, M.,Zakian, S.,Singleton, M.R.,Surrey, T.,Toda, T.
An unconventional interaction between Dis1/TOG and Mal3/EB1 in fission yeast promotes the fidelity of chromosome segregation.
J. Cell. Sci., 129:4592-4606, 2016

PubMed Abstract: Dynamic microtubule plus-ends interact with various intracellular target regions such as the cell cortex and the kinetochore. Two conserved families of microtubule plus-end-tracking proteins, the XMAP215, ch-TOG or CKAP5 family and the end-binding 1 (EB1, also known as MAPRE1) family, play pivotal roles in regulating microtubule dynamics. Here, we study the functional interplay between fission yeast Dis1, a member of the XMAP215/TOG family, and Mal3, an EB1 protein. Using an in vitro microscopy assay, we find that purified Dis1 autonomously tracks growing microtubule ends and is a bona fide microtubule polymerase. Mal3 recruits additional Dis1 to microtubule ends, explaining the synergistic enhancement of microtubule dynamicity by these proteins. A non-canonical binding motif in Dis1 mediates the interaction with Mal3. X-ray crystallography shows that this new motif interacts in an unconventional configuration with the conserved hydrophobic cavity formed within the Mal3 C-terminal region that typically interacts with the canonical SXIP motif. Selectively perturbing the Mal3-Dis1 interaction in living cells demonstrates that it is important for accurate chromosome segregation. Whereas, in some metazoans, the interaction between EB1 and the XMAP215/TOG family members requires an additional binding partner, fission yeast relies on a direct interaction, indicating evolutionary plasticity of this critical interaction module.

PubMed: 27872152
DOI: 10.1242/jcs.197533

Experimental method

X-RAY DIFFRACTION (2.83 Å)