TABLE 2.
Epigenetic regulation of rDNA silencing in mammalsa
| Modification | Gene | Target residue(s) | Effect on rDNA silencing | Reference(s) |
|---|---|---|---|---|
| DNA methylation | DNMT1 | CpG | + | 60, 62 |
| DNMT3a | CpG | + | 60, 62 | |
| DNMT3b | CpG | + | 64 | |
| Acetylation | TIP60/KAT5 | H2AK5, H3K14, H4K5, H4K8, H4K12, H4K16 | ND | 96, 186, 214 |
| MOF/KAT8 | H4K16 | +/− | 51 | |
| Deacetylation | HDAC1 | H3K9ac, H4ac | + | 44, 48 |
| SIRT1 | H3K9ac, H3K14ac, H4K16ac | + | 53, 99 | |
| Methylation | EZH2/KMT6A | H3K27me3 | ND | 215 |
| PRMT5 | H3R8me2, H4R3me2 | + | 82 | |
| SETDB1/KMT1E | H3K9me1/2 | + | 77 | |
| SUV39H1/KMT1A | H3K9me1/2/3 | + | 53 | |
| SUV4-20H2/KMT5C | H4K20me3 | + | 80, 81 | |
| Demethylation | JHDM1A/KDM2A | H3K36me1/2 | + | 83 |
| JHDM1B/KDM2B | H3K4me3 | + | 84 | |
| JMJD2B/KDM4B | H3K9me3 | − | 85 | |
| PHF8/KDM7C | H3K9me2 | − | 86 | |
| PARylation | PARP1 | H3 | + | 111 |
| Ubiquitylation | UHRF1 | H3K23ub | + | 109 |
| RING1B | H2AK119ub | ND | 215 | |
| Deubiquitylation | USP21 | H2AK119ub | ND | 216 |
a
“+,” inducer for rDNA silencing or transcriptional repression; “−,” repressor of rDNA silencing or transcriptional repression; ND, not determined; “H2AK5,” histone H2A at lysine 5; “H2AK119ub,” ubiquitylated histone H2A at lysine 119.