Home | Legals | Sitemap | KIT

Karlsruhe Institute of Technology - KIT
Institute for Applied Biosciences
Department of Microbiology


Fritz-Haber-Weg 4

Geb. 30.43, 3. OG

D-76187 Karlsruhe


Phone:  +49 721 608-44630

Secret.: +49 721 608-44632

Fax:      +49 721 608-44509



reinhard fischerIvo3∂kit edu

Yu et al., 2016

Yu 2016
Nature Microbiology Feb. 2016
cover Nature
Light sensing through the Hog pathway

Fungi use the SakA (HogA) pathway for phytochrome-dependent light signalling


Stress-sensing in fungi depends on a signalling cascade comprised of a two-component phosphorylation relay plus a subsequent MAP kinase cascade to trigger gene expression. Besides osmotic or oxidative stress, fungi sense many other environmental factors, one of which is light. Light controls morphogenetic pathways but also the production of secondary metabolites such as penicillin. Here we show that phytochrome-dependent light signalling in Aspergillus nidulans involves the stress-sensing and osmosensing signalling pathway. In a screening for ‘blind’ mutants, the MAP kinase SakA (also known as HogA) was identified by whole-genome sequencing. The phytochrome FphA physically interacted with the histidine-containing phosphotransfer protein YpdA and caused light-dependent phosphorylation of the MAP kinase SakA and its shuttling into nuclei. In the absence of phytochrome, SakA still responded to osmotic stress but not to light. The SakA pathway thus integrates several stress factors and can be considered to be a hub for environmental signals.