title: Tip-to-tip interaction in the crystal packing of PACSIN 2 is important in regulating tubulation activity.
abstract: The F-BAR domain containing proteins PACSINs are cytoplasmic phosphoproteins involved in various membrane deformations, such as actin reorganization, vesicle transport and microtubule movement. Our previous study shows that all PACSINs are composed of crescent shaped dimers with two wedge loops, and the wedge loop-mediated lateral interaction between neighboring dimers is important for protein packing and tubulation activity. Here, from the crystal packing of PACSIN 2, we observed a tight tip-to-tip interaction, in addition to the wedge loop-mediated lateral interaction. With this tip-to-tip interaction, the whole packing of PACSIN 2 shows a spiral-like assembly with a central hole from the top view. Elimination of this tip-to-tip connection inhibited the tubulation function of PACSIN 2, indicating that tip-to-tip interaction plays an important role in membrane deformation activity. Together with our previous study, we proposed a packing model for the assembly of PACSIN 2 on membrane, where the proteins are connected by tip-to-tip and wedge loop-mediated lateral interactions on the surface of membrane to generate various diameter tubules.
authors.affiliation: State Key Lab of Protein and Plant Gene Research, School of Life Sciences, Peking University, Beijing, 100871, China. xiaofengz@pku.edu.cn.|Department of Biochemistry and Molecular Biology, School of Life Sciences, Peking University, Beijing, 100871, China. xiaofengz@pku.edu.cn.
authors.forename: Xiaoyun
authors.initials: X
authors.lastname: Bai
authors.affiliation: State Key Lab of Protein and Plant Gene Research, School of Life Sciences, Peking University, Beijing, 100871, China.|Department of Biochemistry and Molecular Biology, School of Life Sciences, Peking University, Beijing, 100871, China.
authors.forename: Xiaofeng
authors.initials: X
authors.lastname: Zheng
mesh_terms: D048868:Adaptor Proteins, Signal Transducing / Q000737:chemistry* / Q000235:genetics; D002462:Cell Membrane / Q000737:chemistry; D018360:Crystallography, X-Ray; D006801:Humans; D008081:Liposomes / Q000737:chemistry; D008958:Models, Molecular; D016297:Mutagenesis, Site-Directed; D054730:Protein Interaction Domains and Motifs; D055503:Protein Multimerization; D020836:Protein Structure, Quaternary; D011994:Recombinant Proteins / Q000737:chemistry / Q000235:genetics; D055672:Static Electricity
chemical_list: D048868:Adaptor Proteins, Signal Transducing; D008081:Liposomes; C120714:PACSIN2 protein, human; D011994:Recombinant Proteins
keywords: PACSIN 2; crystal packing; tip-to-tip interaction; tubulation; wedge loop