N⁶‐methyladenine functions as a potential epigenetic mark in eukaryotes

Abstract

N(6)-methyladenine (6mA) is one of the most abundant types of DNA methylation, and plays an important role in bacteria; however, its roles in higher eukaryotes, such as plants, insects, and mammals, have been considered less important. Recent studies highlight that 6mA does indeed occur, and that it plays an important role in eukaryotes, such as worm, fly, and green algae, and thus the regulation of 6mA has emerged as a novel epigenetic mechanism in higher eukaryotes. Despite this intriguing development, a number of important issues regarding its biological roles are yet to be addressed. In this review, we focus on the 5mC and 6mA modifications in terms of their production, distribution, and the erasure of 6mA in higher eukaryotes including mammals. We perform an analysis of the potential functions of 6mA, hence widening understanding of this new epigenetic mark in higher eukaryotes, and suggesting future studies in this field.

N6-Methyladenine: A Conserved and Dynamic DNA Mark

“…6mA was detected in Drosophila, calf thymus, and human placental samples by dot blots (Achwal et al 1983). A recent paper detected 6mA by immunofluorescence in mouse heart tissues (Sun et al 2015). Another group identified 6mA in the plants Oryza sativa and Zea mays, rat tissues, and human cells by high performance liquid chromatography coupled with mass spectrometry (HPLC-ms/ms) (Huang et al 2015).…”

De novoIdentification of DNA Modifications Enabled by Genome-Guided Nanopore Signal Processing

“…DNA modifications are essential across the three kingdoms of life 1 , and are used by cells for defense, gene regulation, cell differentiation, and the transmission of regulatory programs across generations. A host of assays have been developed to detect specific modified nucleotides, including and especially 5mC and 6mA, which are widely deployed by prokaryotes and eukaryotes [2][3][4] . Techniques exist to detect a diverse group of epigenetic modifications through the observation of DNA Pol II kinetics leveraging Single Molecule Real-Time sequencing (SMRT-seq) platform 5,6 .…”

Unravelling the complex mechanisms of transgenerational epigenetic inheritance

“…In mammals, 5-methylcytosine (5mC) is the predominant form of methylated DNA. In organisms (e.g., bacteria, fungi, Caenorhabditis elegans and Drosophila melanogaster) that lack or have low levels of 5mC, other forms of methylated DNA, such as the recently identified N6-methyladenine (6mA), are widespread [11]. 5mC is generally associated with gene repression [12] whereas 6mA is thought to promote activity [13].…”