A conserved function of corepressors is to nucleate assembly of the preinitiation complex

The plant corepressor TPL is recruited to diverse chromatin contexts, yet its mechanism of repression remains unclear. Previously, we have leveraged the fact that TPL retains its function in a synthetic transcriptional circuit in the yeast model Saccharomyces cerevisiae to localize repressive function to two distinct domains. Here, we employed two unbiased whole genome approaches to map the physical and genetic interactions of TPL at a repressed locus. We identified SPT4, SPT5 and SPT6 as necessary for repression with the SPT4 subunit acting as a bridge connecting TPL to SPT5 and SPT6. We also discovered the association of multiple additional constituents of the transcriptional preinitiation complex at TPL-repressed promoters, specifically those involved in early transcription initiation events. These findings were validated in yeast and plants through multiple assays, including a novel method to analyze conditional loss of function of essential genes in plants. Our findings support a m..., Two independent crosses of YNL3669 (MATa SPARCH1-H5[pTDH3-AtTPLH1-5-IAA14-ttACS, pRPS2-AtAFB2-ttCIT1, LEU2, pADH1-AtARF19-ttADH1, pP3(2x)-UbiVenus-ttCYC1] HO::ACT1pr-tdTomato::hphMX, can1∆::STE2pr-Sphis5 lyp1∆ his3∆1 leu2∆0 ura3∆0 met15∆0) and YNL3670 (MATa SPARCTPLN188[pTDH3-AtTPLN188-IAA14-ttACS, pRPS2-AtAFB2-ttCIT1, LEU2, pADH1-AtARF19-ttADH1, pP3(2x)-UbiVenus-ttCYC1 ] HO::ACT1pr-tdTomato::hphMX, can1∆::STE2pr-Sphis5 lyp1∆ his3∆1 leu2∆0 ura3∆0 met15∆0) with the yeast nonessential deletion collection and a set of conditional temperature-sensitive alleles of essential genes were performed following standard SGA procedures104. Final arrays were pinned in duplicate on either SD/MSG–his–leu+ 200mg/mL G418 (untreated) or YPD supplemented with 50mM NAA and grown for 24hr before fluorescence scanning. The Typhoon TrioVariable Mode Imager (GEHealthcare) was used to acquire Venus (488-nmlaser, 520/40BP emission filter) and tdTomato (532-nmlaser, 610/30BPemission filter) fluorescence values. Fo..., , # Identifying the TPL genetic interaction network in yeast through Reporter Synthetic Genetic Array (R-SGA) - Raw data and analysis

[https://doi.org/10.5061/dryad.x0k6djhst](https://doi.org/10.5061/dryad.x0k6djhst)

Give a brief summary of dataset contents, contextualized in experimental procedures and results.

## Description of the R-SGA data and file structure

Two independent crosses of YNL3669 (*MAT**a** SPARCH1-H5[pTDH3-AtTPLH1-5-IAA14-ttACS, pRPS2-AtAFB2-ttCIT1, LEU2, pADH1-AtARF19-ttADH1, pP3(2x)-UbiVenus-ttCYC1*] *HO::ACT1pr-tdTomato::hphMX, can1∆::STE2pr-Sphis5 lyp1∆ his3∆1 leu2∆0 ura3∆0 met15∆0*) and YNL3670 (*MATa SPARCTPLN188[pTDH3-AtTPLN188-IAA14-ttACS, pRPS2-AtAFB2-ttCIT1, LEU2, pADH1-AtARF19-ttADH1, pP3(2x)-UbiVenus-ttCYC1 ] HO::ACT1pr-tdTomato::hphMX, can1∆::STE2pr-Sphis5 lyp1∆ his3∆1 leu2∆0 ura3∆0 met15∆0*) with the yeast nonessential deletion collection and a set of conditional temperature-sensitive alleles of essential genes were performed following standard SGA pro...