Table 1. Conservation of silencing proteins in S.cerevisiae and S.pombe.
| S.cerevisiae | Functions in S.cerevisiae in addition to silencing | Homolog in S.pombea | Silencing function in S.pombe |
|---|---|---|---|
| Sir1p | None | ||
| Sir2p | NAD-dependent HDAC; aging; DNA repair; Pachytene checkpoints; telomere structure; mating-type switching | spSir2 (158) | |
| Sir3p | DNA repair; aging; telomere structure | None | |
| Sir4p | DNA repair; aging; telomere structure | None | |
| Hst1-4p | Homolog of Sir2p, cell cycle; chromosome stability | SpHst2, spHst4 (158) | + |
| Orc1p | DNA replication | Orp1p (264) | |
| Abf1p | Gene activation | SPCC663.05Cb | |
| Rap1p | Gene activation and repression; telomere function; replication | SPBC1778.02 | |
| Sum1p | Transcriptional repression | Sum1 (265) | |
| Rif1p, Rif2p | Regulator of telomere structure | None | |
| Sas4p | Regulator of chromatin structure | None | |
| Sas5p | Regulator of chromatin structure | YD67 (142) | |
| Mga2p, Spt23 | Regulator of chromatin structure; transcription activation | SPAC26H5.05 | |
| Scs2p | Synthesis or processing of phospholipids | Unknown | |
| Hda1p | HDAC | Hda1 (214), Clr3 (196) | + |
| Rpd3p | HDAC | Clr6 (196) | + |
| Sds3p | Component of Rpd3 HDAC complex | Unknown | |
| Sin3p | Component of Rpd3 HDAC complex | Pst1 (266) | |
| Pho23p | Component of Rpd3 HDAC complex | Png1, Png2 (267) | |
| Sas2p, Sas3p | Histone acetylase homolog | SpSas (135) | |
| yCAF-I | Chromatin assembling; DNA repair | Unknown | |
| Asf1p, Asf2p | Chromatin assembling | SPCC663.05C | |
| Set1p, Set2pc | DNA repair; regulation of chromatin structure | Clr4, SP CC306.04C | + |
| Rad6p | DNA repair; sporation; recombination; ubiquitination | Rhp6 (234) | + |
| Ku70, Ku80 | DNA repair; telomere function | Pku70 (239) | |
| Mec3p | DNA damage checkpoint; telomere functions | Hus1(268) | |
| Mec1p | DNA damage checkpoint; telomere functions | Rad3 (245) | |
| Mrc1p | DNA damage checkpoint | SPAC694.06C | |
| Rad53p | DNA damage checkpoint; telomere functions | Cds1 (269) | |
| Pch2p | DNA damage checkpoint | None | |
| Zip1p | DNA damage checkpoint | None | |
| Dot1p | DNA damage checkpoint | None | |
| PCNA | DNA replication and repair | Pcn1 (270) | |
| Rfc1p (RF-C) | DNA replication and repair checkpoints | Rfc1 (271) | |
| Pol2p (scPolɛ) | DNA replication and checkpoints | spPolɛ (272) | |
| Pol1p (scPolα) | DNA replication | Polα (spPolα) (257,258) | + |
| Net1p | Cell cycle; nucleolar structure; rDNA synthesis | Unknown | |
| None | Swi6 | + | |
| None | Rik1 | + |
aGenes encoding putative S.pombe homolog of S.cerevisiae silencing protein are listed by their access numbers, which are accessible at http://www.sanger.ac.uk/cgi-bin/yeastpub/comp_class_search.p.
bSPAC694.06C is probably the S.pombe ortholog of Mrc1p (V.Wood, personal communication).
cSet2p contains the SET domain and cysteine-rich regions shared by Clr4 and SUV39H1 (199).