濡木研公開ラボセミナー

In situ structural studies of macro molecular complexes by cryo-electron tomography with Volta phase plate

福田 善之博士(Max Planck Institute of Biochemistry)

2017年12月04日(Mon)    18:30-19:30  理学部2号館 講堂   

In situ studies of molecular sociology and macro molecular assemblies are critical for our understanding of cellular functions.
Cryo-electron tomography (CET) provides a means of studying the three dimensional structure of pleomorphic objects, such as cells preserved in their natural environment, with spatial resolution in the low nanometer range. To improve image contrast in cryo-electron microscopy, the Volta phase plate (VPP) has been developed. The VPP improves visibility of cellular architecture in CET.
Due to the better visibility in CET provided by VPP, macro molecular complexes such as 26S proteasome and tripeptidyl peptidase II (TPPII) could be detected directly in primary cultured neurons. The image processing after CET showed different conformational states of these complexes and revealed spatial association between TPPII and 26S proteasome. Furthermore, CET with VPP visualized membrane accessories in Thermoplasma acidophilum which have not been observed by classic TEM.

Thus, the CET with VPP has a potential to open a window to the next stage of cellular ultrastructural morphology.