title: Mitogen-activated protein kinase Hog1 is activated in response to curcumin exposure in the budding yeast Saccharomyces cerevisiae.
abstract: BACKGROUND
  Curcumin (CUR), an active polyphenol derived from the spice turmeric, has been traditionally used for centuries in ancient Indian medicine to treat a number of diseases. The physiological effects of CUR have been shown to be diverse; however, the target molecules and pathways that CUR affects have yet to be fully described.
  
  
  RESULTS
  Here, we demonstrate for the first time that the budding yeast mitogen-activated protein kinase (MAPK) Hog1 is essential for the response to CUR. Moreover, CUR-induced Hog1 phosphorylation was rescued by supplementation of iron to the growth medium. Hog1 was rapidly phosphorylated upon CUR treatment, but unlike the response to hyperosmotic shock (0.8 M NaCl), it remains activated for an extended period of time. A detailed analysis of HOG pathway mutants revealed that Pbs2p, Ptc2p, and Ssk2p are required for optimal CUR-induced Hog1 phosphorylation. We also observed a Hog1 dependent transcriptional response to CUR treatment that involved the up-regulation of glycerol-3-phosphate dehydrogenase 1 (GPD1), a factor that is essential for the hyperosmotic stress response.
  
  
  CONCLUSIONS
  Our present finding revealed the role of Hog1 MAPK in regulation of CUR-induced transcriptional response. We anticipate that our finding will enhance the understanding on the molecular mode of action of CUR on S. cerevisiae.
authors.affiliation: Laboratory of Chromatin Biology, Department of Biological Sciences, Indian Institute of Science Education and Research, Bhopal, 462023, India. gajendra@iiserb.ac.in.|Current address: Department of Genetics, Institute of Life Sciences, The Hebrew University of Jerusalem, Jerusalem, 91904, Israel. gajendra@iiserb.ac.in.
authors.forename: Gajendra Kumar
authors.initials: GK
authors.lastname: Azad
authors.affiliation: Laboratory of Chromatin Biology, Department of Biological Sciences, Indian Institute of Science Education and Research, Bhopal, 462023, India. vikash@iiserb.ac.in.
authors.forename: Vikash
authors.initials: V
authors.lastname: Singh
authors.affiliation: Laboratory of Chromatin Biology, Department of Biological Sciences, Indian Institute of Science Education and Research, Bhopal, 462023, India. thakarej@iiserb.ac.in.
authors.forename: Mayur Jankiram
authors.initials: MJ
authors.lastname: Thakare
authors.affiliation: Laboratory of Chromatin Biology, Department of Biological Sciences, Indian Institute of Science Education and Research, Bhopal, 462023, India. shivani.aquarian@gmail.com.
authors.forename: Shivani
authors.initials: S
authors.lastname: Baranwal
authors.affiliation: Laboratory of Chromatin Biology, Department of Biological Sciences, Indian Institute of Science Education and Research, Bhopal, 462023, India. rst@iiserb.ac.in.
authors.forename: Raghuvir Singh
authors.initials: RS
authors.lastname: Tomar
mesh_terms: D003470:Culture Media / Q000737:chemistry; D030024:Curcuma / Q000737:chemistry; D003474:Curcumin / Q000302:isolation & purification / Q000378:metabolism*; D020869:Gene Expression Profiling; D015971:Gene Expression Regulation, Enzymologic; D007501:Iron / Q000378:metabolism; D020928:Mitogen-Activated Protein Kinases / Q000378:metabolism*; D010766:Phosphorylation; D011499:Protein Processing, Post-Translational; D012441:Saccharomyces cerevisiae / Q000187:drug effects* / Q000201:enzymology*; D029701:Saccharomyces cerevisiae Proteins / Q000378:metabolism*
chemical_list: D003470:Culture Media; D029701:Saccharomyces cerevisiae Proteins; D007501:Iron; C088589:HOG1 protein, S cerevisiae; D020928:Mitogen-Activated Protein Kinases; D003474:Curcumin