ERAD components are transcriptionally regulated by the UPR, whereas others are constitutively expressed (Feng et al. 2011; Pinter et al.
2019; Travers et al. 2000). Deletion of derA
(DER1) in A. niger increased the yield of
secreted glucoamylase-glucuronidase (CarFig. 3.4 UPR-mediated control of pathogenic development and mating-type signaling in U. maydis. Interaction between mating-type signaling and the UPR is
realized on different levels. (a) UPR activity is specifically induced after penetration of the plant surface and
facilitates fungal proliferation in planta via Clp1/Cib1
complex formation. UPR activity prior to plant penetration inhibits filamentous growth by Rok1-dependent
dephosphorylation of the MAPK Kpp2. (b) Crosstalk
between UPR and mating-type pathways via the Clp1/
Cib1 interaction and by UPR-controlled Rok1 activity
regulates the virulence potential and biotrophic development by balancing of mating-type signaling and UPR
activity. This figure is adapted from published data
(Schmitz et al. 2019b) (CC-BY 4.0)
3 Genetics of the Unfolded Protein Response in Fungi
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