As 2023 winds down after an incredibly eventful year, the global scientific community is in its familiar rhythm of gathering the fruits of their labor. Researchers worldwide are wrapping up their manuscripts, sending them off to journals, or sharing them on platforms like bioRxiv. Within the last two weeks we have seen many labs preprinting papers, some of them having multiple new exciting stories that will have a huge impact in plant science. Witnessing this evolution within the plant science community is truly remarkable, especially as more scientists embrace the principles of open science by endorsing preprints. Despite the transitions from Tübingen to Bochum and the inevitable hiccups that followed, our momentum still persists. #TheUstunLab has been productive in 2023 and published one research paper, two reviews, one commentary in Nature Plants, two collaborative preprints on nanodomains and plant autophagy
In 2022 and 2023, we have been busy writing reviews about the “Interplay between autophagy and proteasome during proteasome turnover” and “The Plant Ubiquitin-Proteasome as a target for microbial manipulation”.
Our first review that appeared in Trends in Plant Science discusses the intricate relationship between two essential cellular degradation pathways: the ubiquitin-proteasome system (UPS) and autophagy. It highlights their individual roles in maintaining cellular homeostasis by clearing malfunctioning or unneeded proteins and reveals their interdependence, which was historically overlooked. We propose future directions to better understand and dissect the interplay of both pathways.
You can find more details here: https://doi.org/10.1016/j.tplants.2023.01.013
In our second invited review in Annual Review of Phytopathology, we describe how the ubiquitin-proteasome system regulates different immunity-related processes and how pathogens (bacteria, viruses, fungi) subvert this to promote disease. Pathogens use intricate tactics to manipulate the UPS, affecting plant immune responses. They utilize effectors to influence the degradation or stability of proteins involved in plant defense. However, this interplay is complex; the UPS is essential for effective plant defense, yet pathogens rely on its proper function for their pathogenicity. This complexity indicates that our understanding remains superficial. Thus, we propose in our review that it is vital to comprehend how the proteasome and its components are finely tuned at various levels. You can read more here:
https://www.annualreviews.org/doi/10.1146/annurev-phyto-021622-110443
Which brings us to our latest published preprint “ER-anchored protein sorting controls the fate of two proteasome activators for intracellular organelle communication during proteotoxic stress”, the SFB1101 funded PhD work of Gautier Langin. As proposed in our review about the proteasome and its role in plant immune reactions, we tried to decipher how proteotoxicity, caused by pathogens, diseases, organelle stress, and Co. is regulated. We show that the proteasome autoregulatory feedback loop acts as a gatekeeper to facilitate the communication between nucleus and chloroplast. In our study we revealed that the ER-anchored protein sorting system (ERAPS) controls the proteasomal degradation or nuclear translocation of proteasome activators NAC53 and NAC78. While both transcription factors activate the proteasome gene expression, they repress photosynthesis-associated nuclear genes during proteotoxicity. It appears that this trade-off is highly “conserved” as other stress conditions and developmental cues also lead to similar responses. We think that our findings also provide a new conceptual framework for understanding the integral role of transcription factors in managing cellular proteostasis under environmental stress, suggesting conservation of these mechanisms across kingdoms. But this is just a small summary and teaser 🙂 We promise it will be a good read over the Christmas holidays, lots of data, and possible future implications on other trade-offs between the proteasome and energy metabolism.
You can find the link here: https://www.biorxiv.org/content/10.1101/2023.12.11.571118v1
If you want to have a quick summary of our paper you can find this on the new biorxiv “addon” ScienceCast (https://sciencecast.org/casts/dypf9lriqtaz) that provides AI-generated summaries for expert and general audience – it is a fantastic tool and surely will help as to disseminate our research.
We are grateful for every feedback, comments and suggestions regarding our manuscript that we will certainly keep in mind before we submit in January 2024. Please don’t hesitate to contact us – we are always happy to discuss science!
TheUstunlab will certainly try to keep its spirit high in 2024 by finalizing papers (e.g., our Autophagy-Auxin-Vacuoles manuscript, cell-type specific autophagy) and participating in collaborative manuscripts on proteostasis (one will appear in the “Compelling Open Questions in Plant Proteolysis Research” in the focus issue on plant proteolysis in The Plant Cell). Hope that all of you won’t have too much stress the days before Christmas and remember: do not submit to journals before christmas 🙂
Happy Holidays to everyone!
TheUstunLab
