title: Crystal and solution structure, stability and post-translational modifications of collapsin response mediator protein 2.
abstract: The collapsin response mediator protein 2 (CRMP-2) is a central molecule regulating axonal growth cone guidance. It interacts with the cytoskeleton and mediates signals related to myelin-induced axonal growth inhibition. CRMP-2 has also been characterized as a constituent of neurofibrillary tangles in Alzheimer's disease. CD spectroscopy and thermal stability assays using the Thermofluor method indicated that Ca2+ and Mg2+ affect the stability of CRMP-2 and prevent the formation of beta-aggregates upon heating. Gel filtration showed that the presence of Ca2+ or Mg2+ promoted the formation of CRMP-2 homotetramers, and this was further proven by small-angle X-ray scattering experiments, where a 3D solution structure for CRMP-2 was obtained. Previously, we described a crystal structure of human CRMP-2 complexed with calcium. In the present study, we determined the structure of CRMP-2 in the absence of calcium at 1.9 A resolution. When Ca2+ was omitted, crystals could only be grown in the presence of Mg2+ ions. By a proteomic approach, we further identified a number of post-translational modifications in CRMP-2 from rat brain hippocampus and mapped them onto the crystal structure.
authors.affiliation: Department of Biochemistry, University of Oulu, Finland.
authors.forename: Viivi
authors.initials: V
authors.lastname: Majava
authors.forename: Noora
authors.initials: N
authors.lastname: Löytynoja
authors.forename: Wei-Qiang
authors.initials: WQ
authors.lastname: Chen
authors.forename: Gert
authors.initials: G
authors.lastname: Lubec
authors.forename: Petri
authors.initials: P
authors.lastname: Kursula
mesh_terms: D000818:Animals; D002118:Calcium / Q000737:chemistry; D002413:Cations, Divalent / Q000737:chemistry; D002942:Circular Dichroism; D018360:Crystallography, X-Ray; D015180:Electrophoresis, Gel, Two-Dimensional; D006624:Hippocampus / Q000737:chemistry; D006358:Hot Temperature; D006801:Humans; D036341:Intercellular Signaling Peptides and Proteins / Q000032:analysis / Q000737:chemistry* / Q000378:metabolism; D013058:Mass Spectrometry; D008958:Models, Molecular; D009419:Nerve Tissue Proteins / Q000032:analysis / Q000737:chemistry* / Q000378:metabolism; D020033:Protein Isoforms / Q000032:analysis; D011499:Protein Processing, Post-Translational; D051381:Rats; D053838:Scattering, Small Angle; D012996:Solutions; D020349:Surface Plasmon Resonance; D014961:X-Ray Diffraction
chemical_list: D002413:Cations, Divalent; D036341:Intercellular Signaling Peptides and Proteins; D009419:Nerve Tissue Proteins; D020033:Protein Isoforms; D012996:Solutions; C095114:collapsin response mediator protein-2; D002118:Calcium