Brausemann Anton, Gerhardt Stefan, Schott Anne-Kathrin, Einsle Oliver, Große-Berkenbusch Andreas, Johnsson Nils, Gronemeyer Thomas
Institute for Biochemistry, Albert-Ludwigs University, 79104 Freiburg, Germany.
Institute of Molecular Genetics and Cell Biology, Ulm University, 89081 Ulm, Germany.
J Struct Biol. 2016 Mar;193(3):157-161. doi: 10.1016/j.jsb.2016.01.004. Epub 2016 Jan 9.
Septins are a conserved family of GTP-binding proteins that assemble into a highly ordered array of filaments at the mother bud neck in Saccharomyces cerevisiae cells. Many molecular functions and mechanisms of the septins in S. cerevisiae were already uncovered. However, structural information is only available from modeling the crystallized subunits of the human septins into the EM cryomicroscopy data of the yeast hetero-octameric septin rod. Octameric rods are the building block of septin filaments in yeast. We present here the first crystal structure of Cdc11, the terminal subunit of the octameric rod and discuss its structure in relation to its human homologues. Size exclusion chromatography analysis revealed that Cdc11 forms homodimers through its C-terminal coiled coil tail.
Septins是一类保守的GTP结合蛋白家族，在酿酒酵母细胞的母芽颈处组装成高度有序的丝状阵列。酿酒酵母中Septins的许多分子功能和机制已经被揭示。然而，结构信息仅来自于将人类Septins的结晶亚基模型化到酵母异源八聚体Septin杆的冷冻电镜数据中。八聚体杆是酵母中Septin丝的构建块。我们在此展示八聚体杆的末端亚基Cdc11的首个晶体结构，并讨论其与人类同源物相关的结构。尺寸排阻色谱分析表明，Cdc11通过其C末端的卷曲螺旋尾巴形成同型二聚体。
