f1絲狀噬菌體在組裝過程中所參與的 蛋白質-蛋白質間交互作用之分析

Abstract

f1絲狀噬菌體為一單股環狀DNA，其genome可以轉譯出十一個蛋白質，其中有五個形成噬菌體外殼，分別是PⅨ、PⅦ、PⅧ、PⅢ和PⅥ；PⅣ形成孔道，讓組裝好的子代可以送出；PⅠ和PⅩⅠ是與噬菌體起始組裝有關；PⅡ、PⅩ、PⅤ是與DNA複製有關。該種噬菌體在從宿主細胞中組裝送出時，不會造成宿主細胞的破裂和死亡，其組裝與釋出細胞膜是相伴進行，且在此過程中，可能有牽涉到一連串蛋白質-蛋白質與蛋白質-DNA的交互作用。除此之外，thioredoxin對於繁衍過程也是必須的，且可能會與g1p作用來啟動組裝的機制。我們同時藉由各種分析檢測這些相關蛋白質之間可能之交互作用，這些結果對於絲狀噬菌體在結構及組裝過程提供了相關訊息。最終目的是希望能把f1噬菌體完整的組裝機制探討清楚，以期能應用在其它病毒組裝的探討，以及增加phage display的應用。

F1 filamentous bacteriophage contains a single strand DNA genome which can be expressed into 11 proteins. Five of these proteins, PIX, PVII, PVIII, PIII and PVI, make up the protein coating of the phage. PIV forms pores which allow assembled progeny phage particles to leave the host. Proteins PI and PXI are involved in phage assembly while PII, PX, PV take parts in DNA replication. Such phage does not burst or kill its host when progenies are released. Assembly and release of viral particles occur simultaneously and a series of protein-protein and protein-DNA interactions may take place during such process. Moreover, thioredoxin is required for viral replication and may interact with g1p in order to activate the assembly mechanism. We examined the possible interactions between several proteins to provide information on the structure and the assembly of filamentous phage. Our final goal is to determine a complete and detailed f1 phage assembly mechanism which could possibly shed light on assemblies of other virus or could be applied to expand the use of phage display.