Sequence Selectivity in the Binding of Melatonin to PhiX174RF DNA

Abstract

Melatonin is an endogenous neurotransmitter that controls the circadian rhythm. When consumed through medication, it has been proven to serve as a treatment for sleep disorders and alleviate sleep quality. Stable levels of melatonin in the human organism are shown to be beneficial as it provides a protective layer to DNA strands ensuring their longevity; however, its excessive consumption may have damaging consequences on the long run. Here we present a study on the sequence selectivity in the binding of melatonin to DNA, intending to show that melatonin targets specific DNA sites. Binding tophiX174RF DNA was assayed using restriction enzyme activity assays employing nine restriction enzymes with differing target sequences and melatonin/DNA base pair ratios ranging 05 – 20. Products of restriction enzyme digests were separated using agarose gel electrophoresis and the relative amounts of digestion product analyzed optically. The results indicated that melatonin selectively bind to DNA, and that upon binding, melatonin nicks DNA strands leading to a potential indication of strand damage in the long run.