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bioRxiv · 10.1101/2022.04.06.487001

Cryo-EM structure of the diapause chaperone artemin

Parvate, A.·Powell, S.·Brookreson, J.·Moser, T.·Novikova, I. V.·Zhou, M.·Evans, J. E.
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Abstract

The protein artemin constitutes over 10% of all protein in Artemia cysts during diapause and acts as both an RNA and protein chaperone. However, its mechanistic details remain elusive since no high-resolution structure of artemin exists. Here we report the full-length structure of artemin at 2.04 [A] resolution. The cryo-EM map contains density for an intramolecular disulfide bond between Cys22-Cys61 and resolves the entire C-terminus extending into the core of the assembled protein cage. We also provide data supporting the role of C-terminal helix F towards stabilizing the dimer form that is believed to be important for its chaperoning activity. We were able to destabilize this effect by placing a tag at the C-terminus to fully pack the internal cavity and cause limited steric hindrance.

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Parvate, A., Powell, S., Brookreson, J., Moser, T., Novikova, I. V., Zhou, M., Evans, J. E.. 2022-04-06. Cryo-EM structure of the diapause chaperone artemin. https://doi.org/10.1101/2022.04.06.487001

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