| Title: | Slow food: insect prey and chitin induce phytohormone accumulation and gene expression in carnivorous Nepenthes plants |
| Author(s): | Yilamujiang A; Reichelt M; Mithofer A; |
| Address: | "Department of Bioorganic Chemistry. Department of Biochemistry, Max Planck Institute for Chemical Ecology, Hans-Knoll-Str. 8, 07745 Jena, Germany. Department of Bioorganic Chemistry amithoefer@ice.mpg.de" |
| ISSN/ISBN: | 1095-8290 (Electronic) 0305-7364 (Print) 0305-7364 (Linking) |
| Abstract: | "BACKGROUND AND AIMS: Carnivorous Nepenthes plants use modified leaves forming pitfall traps to capture and digest prey, mainly insects, for additional nutrient supply. These traps, so called pitchers, contain a plant-derived fluid composed of many hydrolytic enzymes and defence-related proteins. In this study, the prey-induced induction of corresponding genes of those proteins and a role for phytohormones in this process was analysed. METHODS: Tissue from insect prey-fed, chitin- and phytohormone-challenged pitchers was harvested and analysed for selected gene expressions by a quantitative PCR technique. Phytohormone levels were determined by LC-MS/MS. Nepenthesin proteolytic activities were measured in the digestive fluid using a fluorescence substrate. KEY RESULTS: Insect prey in the pitchers induced the accumulation of phytohormones such as jasmonates as well as the transcription of studied genes encoding a chitinase 3 and a protease (nepenthesin I), whereas a defence-related protein (PR-1) gene was not induced. Treatment with chitin as a component of the insects' exoskeleton triggered the accumulation of jasmonates, the expression of nepenthesin I and chitinase 3 genes similar to jasmonic acid treatment, and induced protease activity in the fluid. All detectable responses were slowly induced. CONCLUSIONS: The results suggest that upon insect prey catch a sequence of signals is initiated: (1) insect-derived chitin, (2) jasmonate as endogenous phytohormone signal, (3) the induction of digestive gene expression and (4) protein expression. This resembles a similar hierarchy of events as described from plant pathogen/herbivore interactions, supporting the idea that carnivory evolved from plant defences" |
| Keywords: | "Animals Carnivory Chitin/*metabolism Cyclopentanes/*metabolism *Gene Expression Regulation, Plant Insecta Magnoliopsida/genetics/*physiology Oxylipins/*metabolism Plant Growth Regulators/*metabolism Plant Proteins/genetics/metabolism Signal Transduction N;" |
| Notes: | "MedlineYilamujiang, Ayufu Reichelt, Michael Mithofer, Axel eng England 2016/06/22 Ann Bot. 2016 Aug; 118(2):369-75. doi: 10.1093/aob/mcw110. Epub 2016 Jun 20" |
