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bioRxiv · 10.1101/2021.02.07.430161

Paip2 associates with PABPC1 on mRNA, and may facilitate PABPC1 dissociation from mRNA upon deadenylation

Xie, J.·Wei, X.·Kozlov, G.·Chen, Y.·Menade, M.·Gehring, K.
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Abstract

Poly(A) binding protein cytoplasmic 1 (PABPC1) is an essential translational initiation factor. PABPC1 recognizes proteins through conserved PABPC1-interacting motifs 1 and 2 (PAM1 and PAM2). PABPC1-interacting protein-2 (Paip2) interacts with PABPC1 and modulates its activities. Here, we report that the formation of Paip2/PABPC1 complex protects it from proteasome independent degradation. We also show that PAM2 is critical for Paip2/PABPC1 interaction in vivo, in agreement with the observation that Paip2 requires PAM2 to interact with PABPC1 on mRNA. Lastly, we propose a role for Paip2 in displacing PABPC1 at the final stage of mRNA deadenylation when the poly(A) tail is partly degraded.

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Xie, J., Wei, X., Kozlov, G., Chen, Y., Menade, M., Gehring, K.. 2021-02-08. Paip2 associates with PABPC1 on mRNA, and may facilitate PABPC1 dissociation from mRNA upon deadenylation. https://doi.org/10.1101/2021.02.07.430161

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