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bioRxiv · 10.1101/2025.08.07.669215

Thermosensitivity of cellular translation restricts the growth of fission yeast at high temperatures

Akikusa, Y.·Yamaguchi, A.·Funahashi, Y.·Mahayot, F.·Naka, T.·Matsuo, A.·Nakase, Y.·Izawa, S.·Shiozaki, K.·Morozumi, Y.
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Abstract

Living organisms have thermal limits above which they are unable to operate and survive. Our previous genetic screen identified proteins that impede the high-temperature growth of fission yeast, including the RNA-binding protein Dri1 and a fission yeast-specific protein termed Rhs1. Here, we show that Dri1 and Rhs1 form a complex and physically interact with the Ccr4-Not complex, a master regulator of mRNA metabolism. Gene expression analysis revealed that the Dri1-Rhs1 and Ccr4-Not complexes negatively regulate a set of genes implicated in ribosome biogenesis (Ribi genes). Loss of the Dri1-Rhs1 complex results in the augmented expression of Ribi genes, thereby suppressing the accumulation of 80S monosomes and the growth inhibition under high-temperature conditions. The thermosensitivity of the translational processes may be a determinant of the upper limit of the growth temperature in fission yeast.

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Akikusa, Y., Yamaguchi, A., Funahashi, Y., Mahayot, F., Naka, T., Matsuo, A., Nakase, Y., Izawa, S., Shiozaki, K., Morozumi, Y.. 2025-08-11. Thermosensitivity of cellular translation restricts the growth of fission yeast at high temperatures. https://doi.org/10.1101/2025.08.07.669215

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