Dataset Information

An end-to-end workflow to study newly synthesized mRNA following rapid protein depletion in Saccharomyces cerevisiae

ABSTRACT: The precise regulation of transcription requires the coordinated activity of numerous proteins and protein complexes. Although significant progress has been made in understanding the mechanisms that regulate transcription, many questions remain unresolved. Accurately defining the direct effects of transcriptional regulators is critical to addressing these questions. An effective approach for identifying the direct targets of transcriptional regulators is combining rapid protein depletion and quantification of newly synthesized RNA. The auxin-inducible degron (AID) system and thiol (SH)-linked alkylation for the metabolic sequencing of RNA (SLAM-seq) are powerful methods to rapidly degrade a target protein and directly quantify newly synthesized RNA, respectively. Both methods have been widely applied to study transcriptional regulation. To address unresolved questions in transcription, we assembled an end-to-end workflow to deplete proteins of interest using the AID system and measure newly synthesized RNA using SLAM-seq in the model eukaryote, Saccharomyces cerevisiae. We provide an open-source, step-by-step protocol to support rapid implementation of this workflow. We include methods for targeted protein degradation, 4-thiouracil (4tU) incorporation, rapid methanol fixation, RNA purification, RNA alkylation, mRNA-seq library construction, and data analysis. Additionally, we demonstrate that this workflow can help define the direct effects of transcriptional regulators using the bromodomain and extra-terminal domain (BET) proteins, Bdf1 and Bdf2, as an example. We provide evidence that data generated using this workflow is robust to normalization using whole-cell spike-in or total read counts, correlates well with 4tU-seq data, and identifies extensive differential expression due to the depletion of Bdf1 and Bdf2. Taken together, this workflow will help address outstanding questions underlying the molecular basis of transcriptional regulation and other processes in S. cerevisiae and other eukaryotes.

ORGANISM(S): Saccharomyces cerevisiae

PROVIDER: GSE261145 | GEO | 2024/03/14

REPOSITORIES: GEO

ACCESS DATA

Similar Datasets

Project description:BACKGROUND:Dynamic transcriptional regulation is critical for an organism's response to environmental signals and yet remains elusive to capture. Such transcriptional regulation is mediated by master transcription factors (TF) that control large gene regulatory networks. Recently, we described a dynamic mode of TF regulation named "hit-and-run". This model proposes that master TF can interact transiently with a set of targets, but the transcription of these transient targets continues after the TF dissociation from the target promoter. However, experimental evidence validating active transcription of the transient TF-targets is still lacking. RESULTS:Here, we show that active transcription continues after transient TF-target interactions by tracking de novo synthesis of RNAs made in response to TF nuclear import. To do this, we introduced an affinity-labeled 4-thiouracil (4tU) nucleobase to specifically isolate newly synthesized transcripts following conditional TF nuclear import. Thus, we extended the TARGET system (Transient Assay Reporting Genome-wide Effects of Transcription factors) to include 4tU-labeling and named this new technology TARGET-tU. Our proof-of-principle example is the master TF Basic Leucine Zipper 1 (bZIP1), a central integrator of metabolic signaling in plants. Using TARGET-tU, we captured newly synthesized mRNAs made in response to bZIP1 nuclear import at a time when bZIP1 is no longer detectably bound to its target. Thus, the analysis of de novo transcripomics demonstrates that bZIP1 may act as a catalyst TF to initiate a transcriptional complex ("hit"), after which active transcription by RNA polymerase continues without the TF being bound to the gene promoter ("run"). CONCLUSION:Our findings provide experimental proof for active transcription of transient TF-targets supporting a "hit-and-run" mode of action. This dynamic regulatory model allows a master TF to catalytically propagate rapid and broad transcriptional responses to changes in environment. Thus, the functional read-out of de novo transcripts produced by transient TF-target interactions allowed us to capture new models for genome-wide transcriptional control. Root protoplasts were transfected with 35S::GR::bZIP1 or Empty vector (EV=pJD385_35S::GR) constructs and cells were sequentially treated with: i) the nitrogen signal (N), ii) cycloheximide (CHX), iii) dexamethasone (DEX; for review see Bargmann et. al 2013). Cells were exposed to 4tU to affinity-label newly synthesized transcripts prior RNA extraction followed by specific pull down of 4tu-fractions and hybridization on Arabidopsis ATH1 microarray chips.

Dataset Information

An end-to-end workflow to study newly synthesized mRNA following rapid protein depletion in Saccharomyces cerevisiae

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure