Purification, crystallization and preliminary X-ray diffraction analysis of Methanococcus jannaschii TATA box-binding protein (TBP)

Introduction TATA box-binding protein (TBP) plays a central role in gene expression through the interactions with RNA polymerase and gene-specific transcription factors. As TBP is one of the common components of eukaryotic and archaeal transcription initiation, the investigation of the structural and functional relationship of TBP in more detail is the most attractive strategy to understand the unity and diversity of the mechanism of transcription initiation among eukaryotes and archaea. The tertiary structure of the core region of eukaryotic TBP showed that TBP has a highly symmetric α/β structure (βαβ4α)2 which contains a unique DNA binding fold. That of archaeal TBP revealed that the folds of archaeal TBP are almost the same as those of eukaryotic TBP, while that surface properties are quite different from eukaryotic ones. The surface charge of eukaryotic TBP is strongly basic whereas archaeal TBP are comparatively neutral, implying that archaeal TBP have distinct interacting factors from eukaryotic TBP. Archaeal TBP can be divided into two groups as group I and II, and only the members of group I are structurally known [1]. Although the tertiary structure of group II archaeal TBP has not been solved, it is likely that group II archaeal TBP have different surface properties and interacting factors from group I archaeal TBP. In fact, one of the group II archaeal TBP (M. jannaschii TBP) shows a weak TATA box-binding activity, unlike eukaryotic and group I archaeal TBP. To analyze the conservation and diversification of the mechanism of actions of TBP at the atomic level, we have initiated structural and functional studies of M. jannaschii TBP. Here we report the purification, crystallization and preliminary crystallographic analysis of M. jannaschii TBP.