title: Interaction of mammalian end binding proteins with CAP-Gly domains of CLIP-170 and p150(glued).
abstract: End binding proteins (EBs) track growing microtubule ends and play a master role in organizing dynamic protein networks. Mammalian cells express up to three different EBs (EB1, EB2, and EB3). Besides forming homodimers, EB1 and EB3 also assemble into heterodimers. One group of EB-binding partners encompasses proteins that harbor CAP-Gly domains. The binding properties of the different EBs towards CAP-Gly proteins have not been systematically investigated. This information is, however, important to compare and contrast functional differences. Here we analyzed the interactions between CLIP-170 and p150(glued) CAP-Gly domains with the three EB homodimers and the EB1-EB3 heterodimer. Using isothermal titration calorimetry we observed that some EBs bind to the individual CAP-Gly domains with similar affinities while others interact with their targets with pronounced differences. We further found that the two types of CAP-Gly domains use alternative mechanisms to target the C-terminal domains of EBs. We succeeded to solve the crystal structure of a complex composed of a heterodimer of EB1 and EB3 C-termini together with the CAP-Gly domain of p150(glued). Together, our results provide mechanistic insights into the interaction properties of EBs and offer a molecular framework for the systematic investigation of their functional differences in cells.
authors: Biomolecular Research, Paul Scherrer Institut, CH-5232 Villigen PSI, Switzerland.
authors: Saša
authors: S
authors: Bjelić
authors: Christian O
authors: CO
authors: De Groot
authors: Martin A
authors: MA
authors: Schärer
authors: Rolf
authors: R
authors: Jaussi
authors: Katja
authors: K
authors: Bargsten
authors: Mara
authors: M
authors: Salzmann
authors: Daniel
authors: D
authors: Frey
authors: Guido
authors: G
authors: Capitani
authors: Richard A
authors: RA
authors: Kammerer
authors: Michel O
authors: MO
authors: Steinmetz
mesh_terms: D000595:Amino Acid Sequence; D018360:Crystallography, X-Ray / Q000379:methods; D000072159:Dynactin Complex; D006801:Humans; D008869:Microtubule-Associated Proteins / Q000378:metabolism* / Q000648:ultrastructure; D008870:Microtubules / Q000378:metabolism; D008969:Molecular Sequence Data; D009363:Neoplasm Proteins / Q000378:metabolism* / Q000648:ultrastructure; D054730:Protein Interaction Domains and Motifs; D017434:Protein Structure, Tertiary
chemical_list: C000606360:DCTN1 protein, human; D000072159:Dynactin Complex; C500985:MAPRE1 protein, human; C403664:MAPRE3 protein, human; D008869:Microtubule-Associated Proteins; D009363:Neoplasm Proteins; C076744:cytoplasmic linker protein 170