Abstract
Processing bodies (P-bodies) are ribonucleoprotein condensates that regulate RNA processing and storage. Although constitutively present in most cells, their size and composition change dynamically in response to developmental and environmental cues. However, mechanisms governing P-body assembly and remodeling remain poorly understood. Here we show that in Arabidopsis, SMG7 interacts with the eIF4A helicases and recruits them to P-bodies. eIF4As limit P-body condensation and also restrict stress granule (SG) formation under heat stress. We further identify meiotic bodies (M-bodies) as composite RNP granules with a P-body core surrounded by a SG-like shell. The SMG7-eIF4A module regulates the recruitment of the meiosis-specific protein TDM1 into M-bodies, thereby influencing meiotic exit and plant reproduction. Our findings suggest that SMG7 functions as an adaptor protein that recruits client proteins into P-bodies and, together with eIF4A, forms a regulatory module that controls P-body composition and maintains their size homeostasis.
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Data availability
Mass spectrometry proteomics data were deposited to the ProteomeXchange Consortium via PRIDE85 partner repository under dataset identifier PXD061406 and 10.6019/PXD061406. The microscopy data generated in this study have been deposited at the EBI bioimage archive (https://www.ebi.ac.uk/bioimage-archive/) under accession number S-BIAD3172. Source data are provided with this paper.
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Acknowledgements
This work was supported by the Czech Science Foundation (EXPRO grant 23-07969X). We thank Richard Stefl for his support and advice with the AF interaction prediction and its structural analysis. We further acknowledge the core facilities of CEITEC Masaryk University for support in obtaining and analyzing scientific data. CELLIM is funded by MEYS CR (LM2023050 Czech-BioImaging), Proteomics Core Facility of CIISB, Instruct-CZ Centre, supported by MEYS CR (LM2023042, CZ.02.01.01/00/23_ 015/0008175, e-INFRA CZ (ID:90254), and Plant Science Core Facility.
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Conceptualization: A.C. and K.R.; methodology: A.C.; formal analysis: A.C., J.S., and D.P.; investigation, A.C., N.S., S.K., J.S., P.M., A.V., and D.P.; writing—original draft: A.C. and K.R.; writing—review and editing: A.C., N.S., S.K., J.S., P.M., A.V., D.P., Z.Z., J.H., and K.R.; visualization: A.C., J.S., P.M., and K.R.; resources: Z.Z., J.H., and K.R.; supervision, A.C. and K.R.; funding acquisition: K.R.
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Cairo, A., Shukla, N., Kanavorova, S. et al. SMG7 and eIF4A constitute a homeostatic module controlling P-body condensation and function of meiotic bodies. Nat Commun (2026). https://doi.org/10.1038/s41467-026-72218-w
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DOI: https://doi.org/10.1038/s41467-026-72218-w
