title: CTTNBP2, but not CTTNBP2NL, regulates dendritic spinogenesis and synaptic distribution of the striatin-PP2A complex.
abstract: Cortactin-binding protein 2 (CTTNBP2) interacts with cortactin to regulate cortactin mobility and control dendritic spine formation. CTTNBP2 has also been associated with autistic spectrum disorder. The regulation of dendritic spinogenesis could explain the association of CTTNBP2 with autism. Sequence comparison has indicated that CTTNBP2 N-terminal-like protein (CTTNBP2NL) is a CTTNBP2 homologue. To confirm the specific effect of CTTNBP2 on dendritic spinogenesis, here we investigate whether CTTNBP2NL has a similar function to CTTNBP2. Although both CTTNBP2 and CTTNBP2NL interact with cortactin, CTTNBP2NL is associated with stress fibers, whereas CTTNBP2 is distributed to the cortex and intracellular puncta. We also provide evidence that CTTNBP2, but not CTTNBP2NL, is predominantly expressed in the brain. CTTNBP2NL does not show any activity in the regulation of dendritic spinogenesis. In addition to spine morphology, CTTNBP2 is also found to regulate the synaptic distribution of striatin and zinedin (the regulatory B subunits of protein phosphatase 2A [PP2A]), which interact with CTTNBP2NL in HEK293 cells. The association between CTTNBP2 and striatin/zinedin suggests that CTTNBP2 targets the PP2A complex to dendritic spines. Thus we propose that the interactions of CTTNBP2 and cortactin and the PP2A complex regulate spine morphogenesis and synaptic signaling.
authors.affiliation: Institute of Molecular Biology, Academia Sinica, Taipei 11529, Taiwan.
authors.forename: Yi-Kai
authors.initials: YK
authors.lastname: Chen
authors.forename: Chiung-Ya
authors.initials: CY
authors.lastname: Chen
authors.forename: Hsiao-Tang
authors.initials: HT
authors.lastname: Hu
authors.forename: Yi-Ping
authors.initials: YP
authors.lastname: Hsueh
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001921:Brain / Q000378:metabolism; D002148:Calmodulin-Binding Proteins / Q000378:metabolism*; D002352:Carrier Proteins / Q000737:chemistry / Q000378:metabolism / Q000502:physiology*; D051356:Cortactin / Q000378:metabolism; D049229:Dendritic Spines / Q000378:metabolism*; D018698:Glutamic Acid / Q000494:pharmacology; D057809:HEK293 Cells; D006624:Hippocampus / Q000166:cytology / Q000378:metabolism; D006801:Humans; D008565:Membrane Proteins / Q000378:metabolism*; D051379:Mice; D008840:Microfilament Proteins / Q000737:chemistry / Q000378:metabolism / Q000502:physiology*; D009419:Nerve Tissue Proteins / Q000737:chemistry / Q000378:metabolism* / Q000502:physiology*; D025941:Protein Interaction Mapping; D051381:Rats; D016415:Sequence Alignment; D020539:Sequence Analysis, Protein; D017385:Sequence Homology; D013569:Synapses / Q000378:metabolism
chemical_list: C580926:CTTNBP2 protein, mouse; C580925:CTTNBP2NL protein, mouse; D002148:Calmodulin-Binding Proteins; D002352:Carrier Proteins; D051356:Cortactin; D008565:Membrane Proteins; D008840:Microfilament Proteins; D009419:Nerve Tissue Proteins; C114095:Strn protein, rat; C411649:zinedin; D018698:Glutamic Acid