Similar Datasets
Project description:Topoisomerases are required to release topological stress generated by RNA polymerase II (RNAPII) during transcription. Here we show that in response to starvation, the complex of topoisomerase 3b (TOP3B) and TDRD3 can promote transcriptional activation or repression. Human HCT116 cells individually inactivated for TOP3B, TDRD3, or TOP3B topoisomerase activity, exhibit similarly disrupted transcription for both starvation-activated genes (SAGs) and starvation-repressed genes (SRGs). Responding to starvation, both TOP3B-TDRD3 and the elongating form of RNAPII exhibit concomitantly increased binding to TOP3B-dependent SAGs, at binding sites that overlap. Strikingly, TOP3B inactivation decreases the binding of elongating RNAPII to TOP3B-dependent SAGs while increased it to SRGs. Furthermore, TOP3B-ablated cells display reduced transcription of several autophagy-associated genes and autophagy per se. Our data suggest that TOP3B-TDRD3 can promote both transcriptional activation and repression by regulating RNAPII distribution. In addition, the findings that it can facilitate autophagy may account for the shortened lifespan of Top3b-KO mice.
2023-02-01 | GSE214322 | GEO
Project description:To identify binding sites and nodule SAGs that are directly targeted by NAC094, we used DAP-seq, which allows the capture of the NAC094 regulatory targets at the whole-genome scale. A total of 2,819 binding peaks corresponding to 2,721 genes were identified from two repeats of the DAP-seq experiment.
2023-03-23 | GSE197359 | GEO
Project description:The study entails novel bio-marker discovery of Tumor Aggressive Grade signature (TAGs) genes and their role in recurrence free survival of breast cancer (BC) patients. Current BC dataset was used for co-expression analysis of TAGs genes and their role in BC progression. Additionally, recent findings have suggested an importance of structural organization of sense-antisense gene pairs (SAGPs) for transcription, post-transcriptional and post-translational events and their associations with cancer and disease. We studied SAGPs in which both gene partners are protein encoding genes (coding-coding SAGPs), their role in human BC development and demonstrated their potential for BC stratification and prognosis. Based on gene expression and correlation analyses we identified the robust set of breast cancer-relevant SAGPs (BCR-SAGPs). We isolated and characterized the sense-antisense gene signature (SAGS) and evaluated its prognostic potential in various gene expression datasets comprising 1161 BC patients. The methods used included the Cox proportional survival analysis, statistical analysis of clinicopathologic parameters and differential gene expression. The SAGS was effective in identification of BC patients with the most aggressive disease. Independently, we validated the SAGS using 58 RNA samples of breast cancer tumors purchased from OriGene Technologies (Rockville, MD).
2015-05-10 | GSE61304 | GEO
Project description:We examined the transcriptome induced by GmNAC81 overexpression and leaf senescence and showed that GmNAC81 further modulates leaf senescence by regulating an extensive repertoire of functionally characterized senescence-associated genes (SAGs). GmNAC81 overexpression also uncovered the regulation of typical drought-responsive genes. Key regulators and effectors of ABA signaling were suppressed by GmNAC81 overexpression.
2020-10-24 | GSE159910 | GEO
Project description:Co-assembly of SAGs from the SAR86 clade
| PRJNA838745 | ENA
Project description:The phytohormone abscisic acid (ABA) induces senescence and facilitates nutrient reuse, which are essential for increasing stress tolerance. Senescence controls plant aging and is closely associated with crop yield and quality. It is a complicated process finely tuned by multiple layers of control. A significant proportion of ABA-responsive genes and cis-elements are targeted by H3K27me3 modification that is mediated by Polycomb group proteins (PcGs); however, the interplay between the major epigenetic machinery and the central stress hormone is poorly understood. Both pathways influence the transcription of thousands of genes, and the dynamic and quantitative epigenomic and transcriptomic changes cannot be characterized with high confidence. This issue is further complicated by the redundant roles of PcG components. This article revealed an intriguing mechanism of the interplay between ABA and PcG in regulating plant senescence, based on the integration of genetic evidence and quantitative comparison of epigenomic data derived from a purpose-developed computational model. We observed that >30% of ABA-induced genes are up-regulated in a double mutant of H3K27me3 methyltransferases CLF and SWN; and the double mutant, but not single-gene mutants, is hyper-sensitive to ABA treatment. Importantly, ABA-triggered H3K27me3 reduction preferentially occurred in regions around senescence-associated genes (SAGs), which are redundantly repressed by CLF and SWN in normal conditions. Furthermore, we revealed that the presence of H3K27me3 surrounding SAGs does not block ABA-induced SAG expression, but rather limits the extent of the induction, thereby preventing an over-sensitive response within a dynamic environment. These findings may serve as a paradigm for the crosstalk between the rapid-effect of phytohormone and the long-term effect of epigenetic machinery in regulating plant environmental responses through modulations of the senescence process.
2018-12-14 | GSE98301 | GEO
Project description:Lettuce (Lactuca sativa L.) is a highly perishable horticultural crop with a relatively short shelf life due to leaf senescence that limits its commercial value and contributes to food waste. Postharvest senescence varies with influences of both environmental and genetic factors. Preharvest genetic factors can be indicative of postharvest quality. Discovery of additional preharvest markers to assess lettuce shelf life is an important step towards increasing the efficiency of lettuce breeding efforts for improved shelf life. We selected and evaluated three romaine lettuces with variable shelf lives with the aim of identifying preharvest markers of lettuce postharvest shelf life. We evaluated leaf morphological characteristics for each of the three cultivars. To assess molecular indicators of shelf life, we used an RNA sequencing approach to construct transcriptomic profiles of two of the cultivars, a short shelf life (SSL) breeding line 60184 and a long shelf life (LSL) cultivar ‘Okeechobee’ at maturity. We identified 552 upregulated and 315 downregulated differentially expressed (DE) genes between the genotypes. We found that 27 % of the DE lettuce genes had an Arabidopsis thaliana ortholog characterized as senescence-associated, indicating that variable expression of senescence-associated genes (SAGs) could serve as a tool for preharvest markers of postharvest shelf life. Notably, we identified several SAGs and functional groupings with highly differential expression between the cultivars. This includes several jasmonate ZIM-domain (JAZ), jasmonic acid (JA) signaling genes, chlorophyll a-b binding (CAB) chloroplast-associated genes, and cell wall modification genes including pectate lyases (PL) and expansins (EXP). This study presented an innovative approach for identifying molecular markers for preharvest factors linked to postharvest traits for prolonged shelf. These genes could potentially be developed further as preharvest predictors of shelf life for lettuce breeding
2024-02-27 | GSE226302 | GEO