In yeast and humans, previous experiences can lead to epigenetic transcriptional memory: repressed genes that exhibit mitotically heritable changes in chromatin structure and promoter recruitment of poised RNA polymerase II preinitiation complex (RNAPII PIC), which enhances future reactivation. Here, we show that INO1 memory in yeast is initiated by binding of the Sfl1 transcription factor to the cis-acting Memory Recruitment Sequence, targeting INO1 to the nuclear periphery. Memory requires a remodeled form of the Set1/COMPASS methyltransferase lacking Spp1, which dimethylates histone H3 lysine 4 (H3K4me2). H3K4me2 recruits the SET3C complex, which plays an essential role in maintaining this mark. Finally, while active INO1 is associated with Cdk8(-) Mediator, during memory, Cdk8(+) Mediator recruits poised RNAPII PIC lacking the Kin28 CTD kinase. Aspects of this mechanism are generalizable to yeast and conserved in human cells. Thus, COMPASS and Mediator are repurposed to promote epigenetic transcriptional poising by a highly conserved mechanism.
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http://dx.doi.org/10.7554/eLife.16691 | DOI Listing |
Proc Natl Acad Sci U S A
January 2025
Center for Nutritional Sciences, Food Science and Human Nutrition Department, College of Agricultural and Life Sciences, University of Florida, Gainesville, FL 32611.
Documented worldwide, impaired immunity is a cardinal signature resulting from loss of dietary zinc, an essential micronutrient. A steady supply of zinc to meet cellular requirements is regulated by an array of zinc transporters. Deletion of the transporter Zip14 (Slc39a14) in mice produced intestinal inflammation.
View Article and Find Full Text PDFProc Natl Acad Sci U S A
January 2025
Department of Immunology and Regenerative Biology, Weizmann Institute of Science, Rehovot 7610001, Israel.
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View Article and Find Full Text PDFProc Natl Acad Sci U S A
January 2025
Department of Plant Pathology, College of Plant Protection, China Agricultural University, Beijing 100193, China.
Host plants and various fungicides inhibit plant pathogens by inducing the release of excessive reactive oxygen species (ROS) and causing DNA damage, either directly or indirectly leading to cell death. The mechanisms by which the oomycete manages ROS stress resulting from plant immune responses and fungicides remains unclear. This study elucidates the role of histone acetylation in ROS-induced DNA damage responses (DDR) to adapt to stress.
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January 2025
Ultrasound in Cardiac Electrophysiology and Biomechanics Key Laboratory of Sichuan Province, Sichuan Provincial People's Hospital, University of Electronic Science and Technology of China, Chengdu, China.
Lung cancer progression is characterized by intricate epigenetic changes that impact critical metabolic processes and cell death pathways. In this study, we investigate the role of histone lactylation at the AIM2 locus and its downstream effects on ferroptosis regulation and lung cancer progression. We utilized a combination of biochemical assays, including chromatin immunoprecipitation (ChIP), quantitative real-time PCR (qRT-PCR), and western blotting to assess histone lactylation levels and gene expression.
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