N6-Methyladenosine in RNA and DNA: An Epitranscriptomic and Epigenetic Player Implicated in Determination of Stem Cell Fate

Table 1

Machinery of adenosine methylation in DNA and RNA.

Machinery	Component	Roles in the complex	Localization	Organism	Biological function
Writers for m6dA	DAMT-1	Methylation of DNA adenosine	Nuclei	C. elegans
Erasers for m6dA	DMAD	Demethylation of m6dA	Nuclei	Drosophila
	NMAD-1	Demethylation of m6dA	Nuclei	C. elegans
	ALKBH1	Demethylation of m6dA and tRNA	Nuclei/cytoplasm	Mammals
	FTO	Demethylation of m6dA and RNA m6A	Nuclei/cytoplasm	Mammals
Readers for m6dA	Unknown	Unknown
Writers for m6A	METTL3	m6A methyltransferase	Nuclei
	METTL14	Core component of the m6A methyltransferase in human	Nuclei
	MT-A70	Complex	Nuclei
	WTAP	Regulatory component of the complex	Nuclei
	KIAA1429	Regulatory component of the complex	Nuclei
Erasers for m6A	ALKBH5	m6A demethylase	Cytoplasm	Mammals	mRNA export and RNA metabolism
	FTO	m6A demethylase	Cytoplasm	Mammals	Mammal fertility convert m6A to h-m6A, f-m6A
Readers for m6A	YTH family
	(i) YTHDF1	m6A reader	Cytoplasm	Mammals	Trigger/enhance translation of mRNA bearing m6A
	(ii) YTHDF2	m6A reader	Cytoplasm		mRNA decay
					Mouse female fertility
					cap-independent
					Translation in nuclear
	(iii) YTHDF3	m6A reader	Cytoplasm	Mammals	Concordance of YTHDF1 and YTHDF2
	(iv) YTHDC1	m6A reader	Nuclei	Mammals	Facilitate inclusion of alternative exons
	(v) YTHDC2	m6A reader	Cytoplasm	Mammals	Fertility of mouse
	hnRNP family
	(i) hnRNP-A2/B1	m6A reader	Cytoplasm	Mammals	Alternative splicing processing of miRNA
	(ii) hnRNP-C	m6A reader	Cytoplasm	Mammals	Alternative splicing processing of miRNA
	(iii) hnRNP-G	m6A reader	Cytoplasm	Mammals
	(iv) hnRNP-H1	m6A reader	Cytoplasm	Mammals
	(v) hnRNP-H2	m6A reader	Cytoplasm	Mammals
	KH/RM/RBD family
	(i) FMR1	m6A reader	Cytoplasm/nuclei mammals		FMR1/YTHDF1 share overlapping mRNA targets
	(ii) FXR1	m6A reader	Cytoplasm/nuclei
	(iii) FXR2	m6A reader	Cytoplasm/nuclei
	(iv) KHSRP	m6A reader	Cytoplasm/nuclei
Repellers for RNA m6A	(i) G3BP1	Repel to m6A	Cytoplasm/nuclei mammals		Positively affect stability of their target mRNAs
	(ii) G3BP2	Repel to m6A	Cytoplasm/nuclei
	(iii) CAPRINI	Repel to m6A	Cytoplasm/nuclei
	(iv) USP10	Repel to m6A	Cytoplasm/nuclei
	(v) METTL16	Repel to m6A	Cytoplasm/nuclei