Université de Fribourg

Multilayered control of protein turnover by torc1 and atg1

Hu, Zehan ; Raucci, Serena ; Jaquenoud, Malika ; Hatakeyama, Riko ; Stumpe, Michael ; Rohr, Rudolf ; Reggiori, Fulvio ; Virgilio, Claudio De ; Dengjel, Jörn

In: Cell Reports, 2019, vol. 28, no. 13, p. 3486-3496.e6

The target of rapamycin complex 1 (TORC1) is a master regulator of cell homeostasis, which promotes anabolic reactions and synchronously inhibits catabolic processes such as autophagy-mediated protein degradation. Its prime autophagy target is Atg13, a subunit of the Atg1 kinase complex that acts as the gatekeeper of canonical autophagy. To study whether the activities of TORC1 and Atg1 are...

Université de Fribourg

A conserved RxLR effector interacts with host RABA-type GTPases to inhibit vesicle-mediated secretion of antimicrobial proteins

Tomczynska, Iga ; Stumpe, Michael ; Mauch, Felix

In: The Plant Journal, 2018, vol. 95, no. 2, p. 187–203

Plant pathogens of the oomycete genus Phytophthora produce virulence factors, known as RxLR effector proteins that are transferred into host cells to suppress disease resistance. Here, we analyse the function of the highly conserved RxLR24 effector of Phytophthora brassicae. RxLR24 was expressed early in the interaction with Arabidopsis plants and ectopic expression in the host enhanced leaf...

Université de Fribourg

Nrf2-mediated fibroblast reprogramming drives cellular senescence by targeting the matrisome

Hiebert, Paul ; Wietecha, Mateusz S. ; Cangkrama, Michael ; Haertel, Eric ; Mavrogonatou, Eleni ; Stumpe, Michael ; Steenbock, Heiko ; Grossi, Serena ; Beer, Hans-Dietmar ; Angel, Peter ; Brinckmann, Jürgen ; Kletsas, Dimitris ; Dengjel, Jörn ; Werner, Sabine

In: Developmental Cell, 2018, vol. 46, no. 2, p. 145-161.e10

Nrf2 is a key regulator of the antioxidant defense system, and pharmacological Nrf2 activation is a promising strategy for cancer prevention and promotion of tissue repair. Here we show, however, that activation of Nrf2 in fibroblasts induces cellular senescence. Using a combination of transcriptomics, matrix proteomics, chromatin immunoprecipitation and bioinformatics we demonstrate that...

Université de Fribourg

The sterol-binding activity of PATHOGENESIS-RELATED PROTEIN 1 reveals the mode of action of an antimicrobial protein

Gamir, Jordi ; Darwiche, Rabih ; Hof, Pieter van't ; Choudhary, Vineet ; Stumpe, Michael ; Schneiter, Roger ; Mauch, Felix

In: The Plant Journal, 2017, vol. 89, no. 3, p. 502–509

Pathogenesis-related proteins played a pioneering role 50 years ago in the discovery of plant innate immunity as a set of proteins that accumulated upon pathogen challenge. The most abundant of these proteins, PATHOGENESIS-RELATED 1 (PR-1) encodes a small antimicrobial protein that has become, as a marker of plant immune signaling, one of the most referred to plant proteins. The biochemical...

Université de Fribourg

Protein phosphatase AP2C1 negatively regulates basal resistance and defense responses to Pseudomonas syringae

Shubchynskyy, Volodymyr ; Boniecka, Justyna ; Schweighofer, Alois ; Simulis, Justinas ; Kvederaviciute, Kotryna ; Stumpe, Michael ; Mauch, Felix ; Balazadeh, Salma ; Mueller-Roeber, Bernd ; Boutrot, Freddy ; Zipfel, Cyril ; Meskiene, Irute

In: Journal of Experimental Botany, 2017, p. -

Mitogen-activated protein kinases (MAPKs) mediate plant immune responses to pathogenic bacteria. However, less is known about the cell autonomous negative regulatory mechanism controlling basal plant immunity. We report the biological role of Arabidopsis thaliana MAPK phosphatase AP2C1 as a negative regulator of plant basal resistance and defense responses to Pseudomonas syringae. AP2C2, a...