Although slugs and snails play important functions in terrestrial ecosystems and
April 26, 2017
Although slugs and snails play important functions in terrestrial ecosystems and cause considerable damage on a variety of crop plants knowledge about the mechanisms of plant immunity to mollusks is limited. mutants with altered levels of specific glucosinolate classes revealed the importance of aliphatic glucosinolates in defending leaves and reproductive structures against mollusks. The presence in mollusk feces of known and novel metabolites arising from glutathione conjugation with glucosinolate hydrolysis products suggests that molluskan herbivores actively detoxify Letrozole glucosinolates. Higher levels of aliphatic glucosinolates were found in plants during the night compared to the day which correlated well with the nocturnal activity rhythms of slugs and snails. Our data spotlight the function of well-known anti-herbivore defense pathways in resistance against slugs and snails and suggest an important role for the diurnal regulation of defense metabolites against nocturnal molluskan herbivores. 2012 Howe& Jander 2008; Wu& Baldwin 2010) the molecular and chemical cues important for plant-mollusk interactions are not well described despite the fact that molluskan herbivores can have large effects on herb overall Defb1 performance and biodiversity (Allan& Crawley 2011) and cause considerable damage in agriculture. In cabbage sunflowers and maize for example slug feeding can be the dominant type of herbivory during the crop establishment phase (Barker 2002). In general plants show Letrozole strong defensive responses upon perceiving an herbivore. Specificity in defense induction is usually mediated by the belief of herbivore-associated molecular patterns (HAMPS) that vary across herbivore species. HAMPS include low molecular excess weight compounds or enzymes present in insect oral secretions that are perceived during feeding and amplify wound induced herb responses (Mithofer& Boland 2008). A common pathway that is activated in reaction to both wounding and herbivory is an increase in the biosynthesis of oxylipins including jasmonic acid (JA) and its isoleucine conjugate (JA-Ile). In several herb species such as thale cress (2003; Sch?fer 2011; Schmelz 2009) which in turn regulates the biosynthesis of defense metabolites (De Geyter 2012). Consequently plants with diminished JA production or belief are generally more susceptible to a wide range of herbivores in the laboratory and the field (Farmer& Dubugnon 2009; Kessler 2004). Many insect herbivores are active during the day and recent experiments in show that JA biosynthesis and signaling can be synchronized with the behavior of an insect herbivore (Goodspeed 2012). Due to its short life cycle small Letrozole genome and ease of transformation has served as a valuable model to decipher JA signaling and defense. plants maintain within their leaves and inflorescences a diverse cache of JA-regulated secondary metabolites. Glucosinolates are sulfur- and nitrogen-containing natural products found in users of the herb order Capparales. Although biologically inactive in their intact form glucosinolates can be hydrolyzed through the action of the enzyme myrosinase which leads to the formation of breakdown products such as isothiocyanates nitriles and epithionitriles in macerated tissues (Halkier& Gershenzon 2006). Breakdown products of glucosinolates appear to be deterrent to most herbivores although some insects have the ability to detoxify glucosinolates upon ingestion (Falk& Gershenzon 2007; Ratzka 2002; Wittstock 2004). Several mutant lines of have been developed that are altered in glucosinolate metabolism including (lacking myrosinase) (reduced levels of indolic glucosinolates) (reduced levels of aliphatic glucosinolates) and 35S:ESP (overexpression of epithiospecifier protein resulting in higher levels of nitriles vs. isothiocyanates) (Barth& Jander 2006; Burow 2006b; Letrozole Sonderby 2007; Zhao 2002). These mutant lines have been used to test the effect of altered glucosinolate metabolism on insect herbivory utilizing many Lepidopteran species (Müller 2010). However since accessions in temperate climates generally overwinter as seeds or rosettes without flowering until the spring (Shindo 2007) and most caterpillars emerge in the summer it is unlikely that herb tissue.