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Genome-editing of a circadian clock gene TaPRR95 facilitates wheat peduncle growth and heading date.Journal of Genetics and Genomics = Yi... Jun 2024Plant height and heading date are important agronomic traits in wheat (Triticum aestivum L.) that affect final grain yield. In wheat, knowledge of pseudo-response...
Plant height and heading date are important agronomic traits in wheat (Triticum aestivum L.) that affect final grain yield. In wheat, knowledge of pseudo-response regulator (PRR) genes on agronomic traits is limited. Here, we identify a wheat TaPRR95 gene by genome-wide association study (GWAS) to be associated with plant height. Triple allele mutant plants produced by CRISPR/Cas9 show increased plant height, particularly at the peduncle, with an earlier heading date. The longer peduncle is mainly caused by the increased cell elongation at its upper section, whilst the early heading date is accompanied with elevated expression of flowering genes, such as TaFT and TaCO1. A peduncle-specific transcriptome analysis reveals up-regulated photosynthesis genes and down-regulated IAA/Aux genes for auxin signaling in prr95 plants that may act as a regulatory mechanism to promote robust plant growth. A haplotype analysis identifies a TaPRR95-B haplotype (Hap2) to be closely associated with reduced plant height and increased thousand-grain weight. Moreover, the Hap2 frequency is higher in cultivars than that in landraces, suggesting the artificial selection on the allele during wheat breeding. These findings suggest that TaPRR95 is a new regulator for plant height and heading date, thereby providing an important target for wheat yield improvement.
PubMed: 38849110
DOI: 10.1016/j.jgg.2024.05.011 -
Plant Communications May 2024The circadian clock entrained by environmental light-dark cycles allows plants to fine-tune diurnal growth and developmental responses. Here, we show that physical...
The circadian clock entrained by environmental light-dark cycles allows plants to fine-tune diurnal growth and developmental responses. Here, we show that physical interactions among evening clock components, including PSEUDO-RESPONSE REGULATOR5 (PRR5), TIMING OF CAB EXPRESSION1 (TOC1), and the Evening Complex (EC) component EARLY FLOWERING 3 (ELF3), define a diurnal repressive chromatin structure specifically at the PHYTOCHROME-INTERACTING FACTOR 4 (PIF4) locus in Arabidopsis. These three clock components act interdependently as well as independently to repress nighttime hypocotyl elongation, as hypocotyl elongation rate dramatically increased specifically at nighttime in the prr5-1 toc1-21 elf3-1 mutant concomitant with a substantial increase in PIF4 expression. Transcriptional repression of PIF4 by ELF3, PRR5, and TOC1 is mediated by the SWI2/SNF2-RELATED (SWR1) chromatin remodeling complex, which incorporates histone H2A.Z at the PIF4 locus, facilitating robust epigenetic suppression of PIF4 during the evening. Overall, these findings demonstrate that the PRR-EC-SWR1 complex represses hypocotyl elongation during the night through a distinctive chromatin domain covering the PIF4 chromatin.
PubMed: 38816994
DOI: 10.1016/j.xplc.2024.100981 -
Journal of the Royal Statistical... Mar 2024In precision medicine, there is much interest in estimating the expected-to-benefit (EB) subset, i.e. the subset of patients who are expected to benefit from a new...
In precision medicine, there is much interest in estimating the expected-to-benefit (EB) subset, i.e. the subset of patients who are expected to benefit from a new treatment based on a collection of baseline characteristics. There are many statistical methods for estimating the EB subset, most of which produce a 'point estimate' without a confidence statement to address uncertainty. Confidence intervals for the EB subset have been defined only recently, and their construction is a new area for methodological research. This article proposes a pseudo-response approach to EB subset estimation and confidence interval construction. Compared to existing methods, the pseudo-response approach allows us to focus on modelling a conditional treatment effect function (as opposed to the conditional mean outcome given treatment and baseline covariates) and is able to incorporate information from baseline covariates that are not involved in defining the EB subset. Simulation results show that incorporating such covariates can improve estimation efficiency and reduce the size of the confidence interval for the EB subset. The methodology is applied to a randomized clinical trial comparing two drugs for treating HIV infection.
PubMed: 38746649
DOI: 10.1093/jrsssc/qlad108 -
Plant Physiology May 2024The circadian system plays a pivotal role in facilitating the ability of crop plants to respond and adapt to fluctuations in their immediate environment effectively....
The circadian system plays a pivotal role in facilitating the ability of crop plants to respond and adapt to fluctuations in their immediate environment effectively. Despite the increasing comprehension of PSEUDO-RESPONSE REGULATORs (PRRs) and their involvement in the regulation of diverse biological processes, including circadian rhythms, photoperiodic control of flowering, and responses to abiotic stress, the transcriptional networks associated with these factors in soybean (Glycine max (L.) Merr.) remain incompletely characterized. In this study, we provide empirical evidence highlighting the significance of GmPRR3b as a crucial mediator in regulating the circadian clock, drought stress response, and abscisic acid (ABA) signaling pathway in soybeans. A comprehensive analysis of DNA affinity purification sequencing and transcriptome data identified 795 putative target genes directly regulated by GmPRR3b. Among them, a total of 570 exhibited a significant correlation with the response to drought, and eight genes were involved in both the biosynthesis and signaling pathways of ABA. Notably, GmPRR3b played a pivotal role in the negative regulation of the drought response in soybeans by suppressing the expression of abscisic acid responsive element-binding factor 3 (GmABF3). Additionally, the overexpression of GmABF3 exhibited an increased ability to tolerate drought conditions, and it also restored the hypersensitive phenotype of the GmPRR3b overexpressor. Consistently, studies on the manipulation of GmPRR3b gene expression and genome editing in plants revealed contrasting reactions to drought stress. The findings of our study collectively provide compelling evidence that emphasizes the significant contribution of the GmPRR3b-GmABF3 module in enhancing drought tolerance in soybean plants. Moreover, the transcriptional network of GmPRR3b provides valuable insights into the intricate interactions between this gene and the fundamental biological processes associated with plant adaptation to diverse environmental conditions.
PubMed: 38717740
DOI: 10.1093/plphys/kiae269 -
Plant Science : An International... Jul 2024The circadian clock plays a critical role in regulating plant physiology and metabolism. However, the way in which the clock impacts the regulation of lipid biosynthesis...
The circadian clock plays a critical role in regulating plant physiology and metabolism. However, the way in which the clock impacts the regulation of lipid biosynthesis in seeds is partially understood. In the present study, we characterized the seed fatty acid (FA) and glycerolipid (GL) compositions of pseudo-response regulator mutants. Among these mutants, toc1 (timing of cab expression 1) exhibited the most significant differences compared to control plants. These included an increase in total FA content, characterized by elevated levels of linolenic acid (18:3) along with a reduction in linoleic acid (18:2). Furthermore, our findings revealed that toc1 developing seeds showed increased expression of genes related to FA metabolism. Our results show a connection between TOC1 and lipid metabolism in Arabidopsis seeds.
Topics: Arabidopsis; Arabidopsis Proteins; Seeds; alpha-Linolenic Acid; Gene Expression Regulation, Plant; Circadian Clocks; Fatty Acids; Transcription Factors; Lipid Metabolism
PubMed: 38599247
DOI: 10.1016/j.plantsci.2024.112087 -
The Plant Cell Apr 2024Little is known about the factors regulating carotenoid biosynthesis in roots. In this study, we characterized DCAR_032551, the candidate gene of the Y locus responsible...
Little is known about the factors regulating carotenoid biosynthesis in roots. In this study, we characterized DCAR_032551, the candidate gene of the Y locus responsible for the transition of root color from ancestral white to yellow during carrot (Daucus carota) domestication. We show that DCAR_032551 encodes a REPRESSOR OF PHOTOSYNTHETIC GENES (RPGE) protein, named DcRPGE1. DcRPGE1 from wild carrot (DcRPGE1W) is a repressor of carotenoid biosynthesis. Specifically, DcRPGE1W physically interacts with DcAPRR2, an ARABIDOPSIS PSEUDO-RESPONSE REGULATOR2 (APRR2)-like transcription factor. Through this interaction, DcRPGE1W suppresses DcAPRR2-mediated transcriptional activation of the key carotenogenic genes phytoene synthase 1 (DcPSY1), DcPSY2, and lycopene ε-cyclase (DcLCYE), which strongly decreases carotenoid biosynthesis. We also demonstrate that the DcRPGE1W-DcAPRR2 interaction prevents DcAPRR2 from binding to the RGATTY elements in the promoter regions of DcPSY1, DcPSY2, and DcLCYE. Additionally, we identified a mutation in the DcRPGE1 coding region of yellow and orange carrots that leads to the generation of alternatively spliced transcripts encoding truncated DcRPGE1 proteins unable to interact with DcAPRR2, thereby failing to suppress carotenoid biosynthesis. These findings provide insights into the transcriptional regulation of carotenoid biosynthesis and offer potential target genes for enhancing carotenoid accumulation in crop plants.
PubMed: 38593056
DOI: 10.1093/plcell/koae111 -
The Plant Journal : For Cell and... Jun 2024Photoperiod insensitivity (auto-flowering) in drug-type Cannabis sativa circumvents the need for short day (SD) flowering requirements making outdoor cultivation in high...
Photoperiod insensitivity (auto-flowering) in drug-type Cannabis sativa circumvents the need for short day (SD) flowering requirements making outdoor cultivation in high latitudes possible. However, the benefits of photoperiod insensitivity are counterbalanced by low cannabinoid content and poor flower quality in auto-flowering genotypes. Despite recent studies in cannabis flowering, a mechanistic understanding of photoperiod insensitivity is still lacking. We used a combination of genome-wide association study and genetic fine-mapping to identify the genetic cause of auto-flowering in cannabis. We then used gene expression analyses and transient transformation assays to characterize flowering time control. Herein, we identify a splice site mutation within circadian clock gene PSEUDO-RESPONSE REGULATOR 37 (CsPRR37) in auto-flowering cannabis. We show that CsPRR37 represses FT expression and its circadian oscillations transition to a less repressive state during SD as compared to long days (LD). We identify several key circadian clock genes whose expression is altered in auto-flowering cannabis, particularly under non-inductive LD. Research into the pervasiveness of this mutation and others affecting flowering time will help elucidate cannabis domestication history and advance cannabis breeding toward a more sustainable outdoor cultivation system.
Topics: Cannabis; Flowers; Photoperiod; Gene Expression Regulation, Plant; Mutation; Plant Proteins; Genome-Wide Association Study; Circadian Clocks; RNA Splice Sites; Circadian Rhythm
PubMed: 38525679
DOI: 10.1111/tpj.16726 -
International Journal of Molecular... Jan 2024Plants monitor day length and memorize changes in temperature signals throughout the day, creating circadian rhythms that support the timely control of physiological and... (Review)
Review
Plants monitor day length and memorize changes in temperature signals throughout the day, creating circadian rhythms that support the timely control of physiological and metabolic processes. The () transcription factors are known as master regulators for the acquisition of cold stress tolerance, whereas () is involved in plant adaptation to heat stress through thermomorphogenesis. Recent studies have shown that circadian clock genes control plant responses to temperature. Temperature-responsive transcriptomes show a diurnal cycle and peak expression levels at specific times of throughout the day. Circadian clock genes play essential roles in allowing plants to maintain homeostasis by accommodating temperature changes within the normal temperature range or by altering protein properties and morphogenesis at the cellular level for plant survival and growth under temperature stress conditions. Recent studies revealed that the central oscillator genes / () and // (//), as well as the () genes (/), were involved in the pathway of the cold signaling transcription factor and regulated the thermomorphogenesis gene . Further studies showed that another central oscillator, (), and the regulatory protein () are also involved. These studies led to attempts to utilize circadian clock genes for the acquisition of temperature-stress resistance in crops. In this review, we highlight circadian rhythm regulation and the clock genes involved in plant responses to temperature changes, as well as strategies for plant survival in a rapidly changing global climate.
Topics: Temperature; Circadian Clocks; Cold Temperature; Circadian Rhythm; Climate
PubMed: 38255990
DOI: 10.3390/ijms25020918 -
European Journal of Nuclear Medicine... May 2024To summarize evidence on the comparative value of amino acid (AA) PET and conventional MRI for prediction of overall survival (OS) in patients with recurrent high grade... (Comparative Study)
Comparative Study
PURPOSE
To summarize evidence on the comparative value of amino acid (AA) PET and conventional MRI for prediction of overall survival (OS) in patients with recurrent high grade glioma (rHGG) under bevacizumab therapy.
METHODS
Medical databases were screened for studies with individual data on OS, follow-up MRI, and PET findings in the same patient. MRI images were assessed according to the RANO criteria. A receiver operating characteristic curve analysis was used to predict OS at 9 months.
RESULTS
Five studies with a total of 72 patients were included. Median OS was significantly lower in the PET-positive than in the PET-negative group. PET findings predicted OS with a pooled sensitivity and specificity of 76% and 71%, respectively. Corresponding values for MRI were 32% and 82%. Area under the curve and sensitivity were significantly higher for PET than for MRI.
CONCLUSION
For monitoring of patients with rHGG under bevacizumab therapy, AA-PET should be preferred over RANO MRI.
Topics: Humans; Bevacizumab; Glioma; Magnetic Resonance Imaging; Positron-Emission Tomography; Brain Neoplasms; Amino Acids; Recurrence; Female; Neoplasm Grading; Male; Survival Analysis; Middle Aged
PubMed: 38228970
DOI: 10.1007/s00259-024-06601-4 -
Physiologia Plantarum 2023Under severe environmental stress conditions, plants inhibit their growth and development and initiate various defense mechanisms to survive. The pseudo-response...
Under severe environmental stress conditions, plants inhibit their growth and development and initiate various defense mechanisms to survive. The pseudo-response regulator (PRRs) genes have been known to be involved in fruit ripening and plant immunity in various plant species, but their role in responses to environmental stresses, especially high salinity and dehydration, remains unclear. Here, we focused on PRRs in tomato plants and identified two PRR2-like genes, SlSRP1 and SlSRP1H, from the leaves of salt-treated tomato plants. After exposure to dehydration and high-salt stresses, expression of SISRP1, but not SlSRP1H, was significantly induced in tomato leaves. Subcellular localization analysis showed that SlSRP1 was predominantly located in the nucleus, while SlSRP1H was equally distributed in the nucleus and cytoplasm. To further investigate the potential role of SlSRP1 in the osmotic stress response, we generated SISRP1-silenced tomato plants. Compared to control plants, SISRP1-silenced tomato plants exhibited enhanced tolerance to high salinity, as evidenced by a high accumulation of proline and reduced chlorosis, ion leakage, and lipid peroxidation. Moreover, SISRP1-silenced tomato plants showed dehydration-tolerant phenotypes with enhanced abscisic acid sensitivity and increased expression of stress-related genes, including SlRD29, SlAREB, and SlDREB2. Overall, our findings suggest that SlSRP1 negatively regulates the osmotic stress response.
Topics: Dehydration; Solanum lycopersicum; Plant Proteins; Sodium Chloride; Abscisic Acid; Stress, Physiological; Plants, Genetically Modified; Gene Expression Regulation, Plant
PubMed: 38148202
DOI: 10.1111/ppl.14082