Targeting Spt5-Pol II by Small-Molecule Inhibitors Uncouples Distinct Activities and Reveals Additional Regulatory Roles

Anat Bahat; Or Lahav; Alexander Plotnikov; Dena Leshkowitz; Rivka Dikstein

doi:10.1016/j.molcel.2019.08.024

Targeting Spt5-Pol II by Small-Molecule Inhibitors Uncouples Distinct Activities and Reveals Additional Regulatory Roles

Mol Cell. 2019 Nov 21;76(4):617-631.e4. doi: 10.1016/j.molcel.2019.08.024. Epub 2019 Sep 26.

Authors

Anat Bahat¹, Or Lahav¹, Alexander Plotnikov², Dena Leshkowitz³, Rivka Dikstein⁴

Affiliations

¹ Department of Biomolecular Sciences, The Weizmann Institute of Science, Rehovot 76100, Israel.
² The Nancy and Stephen Grand Israel National Center for Personalized Medicine, The Weizmann Institute of Science, Rehovot 76100, Israel.
³ Bioinformatics Unit, Department of Life Sciences Core Facilities, The Weizmann Institute of Science, Rehovot 76100, Israel.
⁴ Department of Biomolecular Sciences, The Weizmann Institute of Science, Rehovot 76100, Israel. Electronic address: rivka.dikstein@weizmann.ac.il.

PMID: 31564557
DOI: 10.1016/j.molcel.2019.08.024

Abstract

Spt5 is a conserved and essential transcription elongation factor that promotes promoter-proximal pausing, promoter escape, elongation, and mRNA processing. Spt5 plays specific roles in the transcription of inflammation and stress-induced genes and tri-nucleotide expanded-repeat genes involved in inherited neurological pathologies. Here, we report the identification of Spt5-Pol II small-molecule inhibitors (SPIs). SPIs faithfully reproduced Spt5 knockdown effects on promoter-proximal pausing, NF-κB activation, and expanded-repeat huntingtin gene transcription. Using SPIs, we identified Spt5 target genes that responded with profoundly diverse kinetics. SPIs uncovered the regulatory role of Spt5 in metabolism via GDF15, a food intake- and body weight-inhibitory hormone. SPIs further unveiled a role for Spt5 in promoting the 3' end processing of histone genes. While several SPIs affect all Spt5 functions, a few inhibit a single one, implying uncoupling and selective targeting of Spt5 activities. SPIs expand the understanding of Spt5-Pol II functions and are potential drugs against metabolic and neurodegenerative diseases.

Keywords: DSIF; GDF15; Huntington disease; NF-κB; Pol II; SPI; Spt4; Spt5; histone genes termination; promoter-proximal pausing.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

3' Untranslated Regions
Animals
Cell Nucleus / drug effects*
Cell Nucleus / enzymology
Chromosomal Proteins, Non-Histone / antagonists & inhibitors*
Chromosomal Proteins, Non-Histone / genetics
Chromosomal Proteins, Non-Histone / metabolism
Drug Discovery / methods
Energy Metabolism / drug effects
Growth Differentiation Factor 15 / genetics
Growth Differentiation Factor 15 / metabolism
HEK293 Cells
HeLa Cells
High-Throughput Screening Assays
Histones / genetics
Histones / metabolism
Humans
Huntingtin Protein / biosynthesis
Huntingtin Protein / genetics
Jurkat Cells
MCF-7 Cells
Mice, Transgenic
Mutation
NF-kappa B / biosynthesis
NF-kappa B / genetics
Nuclear Proteins / antagonists & inhibitors*
Nuclear Proteins / genetics
Nuclear Proteins / metabolism
RNA Polymerase II / genetics
RNA Polymerase II / metabolism*
Transcription, Genetic / drug effects*
Transcriptional Activation / drug effects*
Transcriptional Elongation Factors / antagonists & inhibitors*
Transcriptional Elongation Factors / genetics
Transcriptional Elongation Factors / metabolism

Substances

3' Untranslated Regions
Chromosomal Proteins, Non-Histone
GDF15 protein, human
Gdf15 protein, mouse
Growth Differentiation Factor 15
HTT protein, human
Histones
Htt protein, mouse
Huntingtin Protein
NF-kappa B
Nuclear Proteins
SUPT5H protein, human
Transcriptional Elongation Factors
SPT5 transcriptional elongation factor
RNA Polymerase II