rylalkylamine N-acetyltransferase: ?Nuclear translocation and potential role in response to blue light in retinal neuron cells?

RIOS, M.N.; MARCHESE, N.A.; GUIDO, M.E.

Carlos Paz

Congreso; XXXIV Reunión Anual SAN 2019; 2019

Sociedad Argentina de Investigación en Neurociencias

Aryalkylamine N-acetyltransferase (AANAT) is the key regulatory enzyme inmelatonin synthesis. AANAT is present in the pineal gland, retina and other regionswhere is controlled by the molecular clock and light. The AANAT stability isregulated by cAMP increase promoting important changes in its activity. Vertebrateretina is a photosensitive tissue and is known that prolonged exposition to bluelight (BL) causes to retinal damage and circadian clock disruption. In additionAANAT belong to GNAT-5 family together with histones acetyl transferases. Herewe investigated the regulation of AANAT and histone 3 acetylation at lysine 27(H3k27) in primary cultures of chicken embryonic retinal cells exposed to differentL conditions. Cultures exhibited BL induction of AANAT as compared with darkcontrols (D). Interestingly AANAT showed a localization change, from thecytoplasm to nucleus, increasing in BL, and remain elevated in darkness 1 h afterBL exposure. Furthermore, high levels of the phosphorylated enzyme weredetected after the BL treatment comparated with the D control, in nuclear fractionsobtained from primary cultures together with a significant increase in H3k27 levelsafter BL treatment. Results suggest that AANAT is a BL-induced enzyme in retinalneuron cells, promoting its phosphorylation and nuclear importation, likely playingimportant roles in nuclear function in response to BL exposure.