Table 1  Mutant hunts that identified key factors in chromatin-mediated transcription in S. cerevisiae
Mutant huntPhenotypeGenes identifiedProtein function
sptaSuppression of Ty and LTR insertion mutationsSPT6/SSN20/CRE2Histone chaperone
SPT16/CDC68bHistone chaperone, part of FACT
HTA1/SPT11, HTB1/SPT12Histones H2A, H2B
SPT4, SPT5Elongation factors; components of DSIF
SPT10/CRE1, SPT21Regulators of histone gene transcription
adacResistance to high levels of Gal4-VP16GCN5/ADA4/AAS104dHistone acetyltransferase; part of the SAGA coactivator complex
NGG1/ADA2,e ADA3Required for Gcn5 activity within SAGA
crefExpression of ADH2 in the presence of glucoseSPT10/CRE1Regulator of histone gene transcription
SPT6/CRE2/SSN20Histone chaperone
swigInability to switch mating type due to reduced HO transcriptionSWI1/SWI2/SWI3Part of the Swi/Snf chromatin-remodeling complex
snfhInability to transcribe SUC2; sucrose nonfermenterSNF2/SNF5/SNF6Part of the Swi/Snf chromatin-remodeling complex
siniSuppression of swi mutationsSPT2/SIN1Transcription elongation factor
HHT1/BUR5/SIN2Histone H3
SIN3/RPD1Cofactor for Rpd3
ssnjSuppression of snf mutationsCYC8/SSN6/CRT8kGlobal repressor; recruits HDACs
SPT6/CRE2/SSN20Histone chaperone
burlSuppression of SUC2 UAS deletionHHT1/BUR5/SIN2Histone H3
hir/hpcmLoss of cell-cycle control of histone gene transcriptionHIR1, HIR2, HIR3, HPC2Nucleosome assembly, transcriptional regulation
rpdnSuppression of trk1ΔSIN3/RPD1Cofactor for Rpd3
RPD3Histone deacetylase
rttoReduces Ty transpositionRTT106Histone chaperone
RTT109H3 K56 HAT
  • Mutant hunts that identified factors included in this chapter are listed. Several other notable yeast mutant hunts have identified key factors in transcription (e.g., Nonet and Young 1989; Pinto et al. 1992). For each mutant hunt, we have usually cited only the publication that isolated the first mutants. The factors listed are grouped by function. Often, more factors than those listed were identified in the cited mutant hunts.

  • a Winston et al. (1984, 1987); Clark-Adams et al. (1988); Fassler and Winston (1988); Natsoulis et al. (1991).

  • b Spt16 was also identified as Cdc68 in a screen for start mutants (Prendergast et al. 1990; Rowley et al. 1991).

  • c Berger et al. (1992); Marcus et al. (1994).

  • d Gcn5 was initially identified as Aas104 (Penn et al. 1983) and later renamed GCN5 when new nomenclature was implemented for genes involved in general amino acid control. Gcn5 was initially suggested to be a coactivater in a subsequent study (Georgakopoulos and Thireos 1992) and then later shown to be a HAT (Brownell et al. 1996).

  • e Ada2 was also identified as Ngg1 (Brandl et al. 1993).

  • f Denis (1984); Denis et al. (1994).

  • g Stern et al. (1984); Breeden and Nasmyth (1987).

  • h (Carlson et al. (1981); Neigeborn and Carlson (1984).

  • i Sternberg et al. (1987).

  • j Carlson et al. (1984); Neigeborn et al. (1986).

  • k SSN6 was initially identified as CYC8 (Rothstein and Sherman 1980), and it was also identified as CRT8 (Zhou and Elledge 1992).

  • l Prelich and Winston (1993).

  • m Osley and Lycan (1987); Xu et al. (1992).

  • n Vidal and Gaber (1991); Vidal et al. (1991).

  • o Scholes et al. (2001).