About the universality of cell responses to UV-B radiation: Abscisic acid and nitric oxide have something to say

LAMATTINA L.; TOSSI V.; CASSIA R.; NEGRI P.; MAGGI M.; RAMIREZ L.; EGUARAS M.; CASSIA R.

Andalucía

Workshop; Enviroment Workshop: Reactive oxygen and nitrogen species and environment: A new vision for 2020.; 2014

Universidad de Andalucía, España.

Herewe present evidences confirming that abscisic acid (ABA) and nitric oxide (NO) are key partnersin plant and animal responses to environmental stress produced by UV-Bradiation. In the past, biological functions of NO in animals have inspired thestudies of NO in plant. In contrast, our knowledge of biological functions of ABA is well known inplants and re-emerging in animals nowadays. More than 50 years ago, It has beenunambiguously demonstrated the ABAoccurrence in lower and higher animals. Hence, we evaluated the parallelisms inABA signallingpathways in plants and animals in response to a common environmental challengelike UV-B. Our results demonstrate the close partnership between ABA and NO in defenceresponses to high doses of UV-B in plant and animal cells. In plants, UV-Binduces a rapid increase in ABAconcentration which is required for the biosynthesis of NO and activation ofgene expression leading to the synthesis of antioxidant compounds. In humankeratinocytes and granulocytes, UV-B triggers the synthesis of ABA that, in an autocrine way, induces thesynthesis of NO and ROS as a prerequisite to develop the inflammatory responsethat follows the exposure to the radiation. Finally, we present data concerningthe role of ABAand NO in honey bees. In the last fifty years, a dramatic drop of thepopulation of honey bees world wide have focused the attention of researchers.In US, the phenomenon was called Colony Collapse Disorder (CCD) since coloniessuffer a rapid loss of adult bees without any apparent cause. ABA is a ubiquitous compound present innectar and pollen, the primary food that honey bees collect to prepare honey.Here we demonstrate, in a combination of field and laboratory experiments, thatABA is anessential component of honey to stimulate innate immune defences and toactivate wound-healing process in larvae and adult honey bees.