Defense, activated/induced

Keywords Marine chemical defense Activated defense Induced defense Plankton Chemical ecology... 

Fig. (3). Hypothetical representation of host defense activation by extracellularly produced H2O2 in GO-transgenic plant. Salicylic acid biosynthesis is elevated through stimulation of benzoic acid 2-hydroxylase activity. The expression of defense-related proteins is induced by increased salicylic acid and perhaps also by H2O2 itself via a separate pathway.

Fig. 4.10 Effects of folivory on jack pine resistance against subcortical insects a) Compromised host defenses against subcortical insects following defoliation by jack pine budworm. b) Defoliated trees also accumulate lower monoterpene concentrations during active induced responses. Light <25% Moderate 26-50% Heavy 51-75% Extreme >76% (with permission from the Ecol. Soc. America).

Interferon (IFN) differs from bona fide antiviral diugs since it is a natural defense protein of the host organism and does not directly interfere with the viral replication steps. Interferons are small glycoproteins inducing immune modulatory and antiviral activities. They are secreted by lymphocytes, leukocytes and fibroblasts in response to foreign nucleic acids (dsRNA). 

---