Mode of action
A mode of action (MoA) describes a functional or anatomical change, at the cellular level, resulting from the exposure of a living organism to a substance. In comparison, a mechanism of action (MOA) describes such changes at the molecular level.
A mode of action is important in classifying chemicals as it represents an intermediate level of complexity in between molecular mechanisms and physiological outcomes, especially when the exact molecular target has not yet been elucidated or is subject to debate. A mechanism of action of a chemical could be “binding to DNA” while its broader mode of action would be “transcriptional regulation”. However, there is no clear consensus and the term mode of action is also often used, especially in the study of pesticides, to describe molecular mechanisms such as action on specific nuclear receptors or enzymes.
- “Mechanisms and mode of dioxin action” (PDF). US EPA. Archived from the original (PDF) on 26 February 2015. Retrieved 11 June 2012.
- Grant RL, Combs AB, Acosta D (2010). “Experimental Models for the Investigation of Toxicological Mechanisms”. In McQueen CA (ed.). Comprehensive Toxicology (2nd ed.). Oxford: Elsevier. p. 204. ISBN 978-0-08-046884-6.
- Ng WL, Kazmierczak KM, Robertson GT, Gilmour R, Winkler ME (Jan 2003). “Transcriptional regulation and signature patterns revealed by microarray analyses of Streptococcus pneumoniae R6 challenged with sublethal concentrations of translation inhibitors”. Journal of Bacteriology. 185 (1): 359–70. doi:10.1128/JB.185.1.359-370.2003. PMC 141824. PMID 12486074.
- “Herbicide Group Classification by Mode of Action”. Alberta Agriculture and Rural Development. Retrieved 11 June 2012.