A Proteome-wide screen for mammalian SxIP motif-containing microtubule plus-end tracking proteins

Curr Biol. 2012 Oct 9;22(19):1800-7. doi: 10.1016/j.cub.2012.07.047. Epub 2012 Aug 9.


Microtubule plus-end tracking proteins (+TIPs) are structurally and functionally diverse factors that accumulate at the growing microtubule plus-ends, connect them to various cellular structures, and control microtubule dynamics [1, 2]. EB1 and its homologs are +TIPs that can autonomously recognize growing microtubule ends and recruit to them a variety of other proteins. Numerous +TIPs bind to end binding (EB) proteins through natively unstructured basic and serine-rich polypeptide regions containing a core SxIP motif (serine-any amino acid-isoleucine-proline) [3]. The SxIP consensus sequence is short, and the surrounding sequences show high variability, raising the possibility that undiscovered SxIP containing +TIPs are encoded in mammalian genomes. Here, we performed a proteome-wide search for mammalian SxIP-containing +TIPs by combining biochemical and bioinformatics approaches. We have identified a set of previously uncharacterized EB partners that have the capacity to accumulate at the growing microtubule ends, including protein kinases, a small GTPase, centriole-, membrane-, and actin-associated proteins. We show that one of the newly identified +TIPs, CEP104, interacts with CP110 and CEP97 at the centriole and is required for ciliogenesis. Our study reveals the complexity of the mammalian +TIP interactome and provides a basis for investigating the molecular crosstalk between microtubule ends and other cellular structures.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Actins / metabolism
  • Amino Acid Motifs*
  • Amino Acid Sequence
  • Animals
  • Cell Cycle Proteins / metabolism
  • Cell Membrane / metabolism
  • Humans
  • Mammals
  • Mass Spectrometry
  • Microtubule-Associated Proteins / analysis
  • Microtubule-Associated Proteins / metabolism*
  • Microtubules / chemistry
  • Microtubules / metabolism
  • Molecular Sequence Data
  • Proteome / analysis
  • Proteomics / methods
  • Signal Transduction


  • Actins
  • CNTRL protein, human
  • Cell Cycle Proteins
  • MAPRE1 protein, human
  • Microtubule-Associated Proteins
  • Proteome