+検索条件
-Structure paper
タイトル | Structural polymorphism of the major capsid protein of a double-stranded RNA virus: an amphipathic alpha helix as a molecular switch. |
---|---|
ジャーナル・号・ページ | Structure, Vol. 13, Issue 7, Page 1007-1017, Year 2005 |
掲載日 | 2005年12月9日 |
著者 | Irene Saugar / Daniel Luque / Ana Oña / José F Rodríguez / José L Carrascosa / Benes L Trus / José R Castón / |
PubMed 要旨 | The infectious bursal disease virus T=13 viral particle is composed of two major proteins, VP2 and VP3. Here, we show that the molecular basis of the conformational flexibility of the major capsid ...The infectious bursal disease virus T=13 viral particle is composed of two major proteins, VP2 and VP3. Here, we show that the molecular basis of the conformational flexibility of the major capsid protein precursor, pVP2, is an amphipatic alpha helix formed by the sequence GFKDIIRAIR. VP2 containing this alpha helix is able to assemble into the T=13 capsid only when expressed as a chimeric protein with an N-terminal His tag. An amphiphilic alpha helix, which acts as a conformational switch, is thus responsible for the inherent structural polymorphism of VP2. The His tag mimics the VP3 C-terminal region closely and acts as a molecular triggering factor. Using cryo-electron microscopy difference imaging, both polypeptide elements were detected on the capsid inner surface. We propose that electrostatic interactions between these two morphogenic elements are transmitted to VP2 to acquire the competent conformations for capsid assembly. |
リンク | Structure / PubMed:16004873 |
手法 | EM (単粒子) |
解像度 | 12.0 - 15.0 Å |
構造データ | EMDB-1115: EMDB-1118: |