Changes in the esophagogastric junction outflow obstruction manometric feature based on the Chicago Classification updates

BACKGROUND The critical diagnostic criteria for esophagogastric junction outflow obstruction(EGJOO)were published in the latest Chicago Classification version 4.0(CCv4.0).In addition to the previous criterion[elevated integrated relaxation pressure(IRP)in supine position],manometric diagnosis of EGJOO requires meeting the criteria of elevated median-IRP during upright wet swallows and elevated intrabolus pressure.However,with the diagnostic criteria modification,the change in manometric features of EGJOO remained unclear.AIM To evaluate the esophageal motility characteristics of patients with EGJOO and select valuable parameters for confirming the diagnosis of EGJOO.METHODS We performed a retrospective analysis of 370 patients who underwent highresolution manometry with 5 mL water swallows×10 in supine,×5 in upright position and the rapid drink challenge(RDC)with 200 mL water from November 2016 to November 2021 at Peking University First Hospital.Fifty-one patients with elevated integrated supine IRP and evidence of peristalsis were enrolled,with 24 patients meeting the updated manometric EGJOO diagnosis(CCv4.0)as the EGJOO group and 27 patients not meeting the updated EGJOO criteria as the isolated supine IRP elevated group(either normal median IRP in upright position or less than 20%of supine swallows with elevated IBP).Forty-six patients with normal manometric features were collected as the normal high-resolution manometry(HRM)group.Upper esophageal sphincter(UES),esophageal body,and lower esophageal sphincter(LES)parameters were compared between groups.RESULTS Compared with the normal HRM group,patients with EGJOO(CCv4.0)had significantly lower proximal esophageal contractile integral(PECI)and proximal esophageal length(PEL),with elevated IRP on RDC(P<0.05 for each comparison),while isolated supine IRP elevated patients had no such feature.Patients with EGJOO also had more significant abnormalities in the esophagogastric junction than isolated supine IRP elevated patients,including higher LES resting pressure(LESP),intrabolus pressure,median supine IRP,median upright IRP,and IRP on RDC(P<0.05 for each comparison).Patients with dysphagia had significantly lower PECI and PEL than patients without dysphagia among the fifty-one with elevated supine IRP.Further multivariate analysis revealed that PEL,LESP,and IRP on RDC are factors associated with EGJOO.The receiver-operating characteristic analysis showed UES nadir pressure,PEL,PECI,LESP,and IRP on RDC are parameters supportive for confirming the diagnosis of EGJOO.CONCLUSION Based on CCv4.0,patients with EGJOO have more severe esophagogastric junction dysfunction and are implicated in the proximal esophagus.Additionally,several parameters are supportive for confirming the diagnosis of EGJOO.

Tensile ductility improvement of AlSi9Cu1 alloy by chemical composition optimization

Diesel engines, characterized by higher breakout pressure and compression ratio in comparison with gasoline engines, require particularly elevated tensile properties for their engine parts. In order to maintain both high strength and high ductility in the cylinder head, i.e., to obtain higher percent elongation without further reducing the tensile strength, Al Si9Cu1 alloy was used to prepare the cylinder head in an aluminum diesel engine. At the same time, the effect of different modification elements, Na or Sr, and Fe content on the reduction of secondary dendrite arm spacing(SDAS) was discussed, and the design of T7 heat treatment parameters were analyzed in order to improve the tensile ductility. The result shows:(1) The SDAS is as small as 18±3 μm for the Sr modified alloy.(2) The percent elongation of the alloy with Sr modification increases by 66.7% and 42.9%, respectively, compared with the unmodified alloy and the alloy with Na modification.(3) Lower Fe content alloy(0.10%) gives good results in percent elongation compared to the alloy with higher Fe content(0.27%); in particular, after Sr modification and T7 heat treatment, the elongation of over 5% is obtained.

Unfolded protein response and storage product accumulation in rice grains

Secretory and transmembrane proteins start to synthesize and fold in the endoplasmic reticulum(ER).When the balance between protein folding demands and protein folding capability in the ER is broken,a well-conserved process known as the unfolded protein response(UPR)is induced to restore protein homeostasis.The grain quality of rice(Oryza sativa L.),one of the most important crops that feed more than half of the world’s population,is determined by the accumulation of nutritional components,such as seed storage proteins(SSPs)and starches in the grains.Rice SSPs are synthesized in the secretory pathways of endosperms and their biosynthesis is subject to complex regulation.Here,we focus on summarizing recent advances in our understanding of the role of UPR in grain development,especially in SSP biosynthesis in rice,and provide future perspectives on unanswered questions on improving grain quality through modulating UPR in rice.

CCaP1/CCaP2/CCaP3 interact with plasma membrane H^(+)-ATPases and promote thermoresponsive growth by regulating cell wall modification in Arabidopsis

Arabidopsis plants adapt to warm temperatures by promoting hypocotyl growth primarily through the basic helix-loop-helix transcription factor PIF4 and its downstream genes involved in auxin responses,which enhance cell division.In the current study,we discovered that cell wall-related calcium-binding protein 2(CCaP2)and its paralogs CCaP1 and CCaP3 function as positive regulators of thermo-responsive hypocotyl growth by promoting cell elongation in Arabidopsis.Interestingly,mutations in CCaP1/CCaP2/CCaP3 do not affect the expression of PIF4-regulated classic downstream genes.However,they do noticeably reduce the expression of xyloglucan endotransglucosylase/hydrolase genes,which are involved in cell wall modification.We also found that CCaP1/CCaP2/CCaP3 are predominantly localized to the plasma membrane,where they interact with the plasma membrane H^(+)-ATPases AHA1/AHA2.Furthermore,we observed that vanadate-sensitive H^(+)-ATPase activity and cell wall pectin and hemicellulose contents are significantly increased in wild-type plants grown at warm temperatures compared with those grown at normal growth temperatures,but these changes are not evident in the ccap1-1 ccap2-1 ccap3-1 triple mutant.Overall,our findings demonstrate that CCaP1/CCaP2/CCaP3 play an important role in controlling thermo-responsive hypocotyl growth and provide new insights into the alternative pathway regulating hypocotyl growth at warm temperatures through cell wall modification mediated by CCaP1/CCaP2/CCaP3.

A near-complete assembly of the Houttuynia cordata genome provides insights into the regulatory mechanism of flavonoid biosynthesis in Yuxingcao

Houttuynia cordata,also known as Yuxingcao in Chinese,is a perennial herb in the Saururaceae family.It is highly regarded for its medicinal properties,particularly in treating respiratory infections and inflammatory conditions,as well as boosting the human immune system.However,a lack of genomic information has hindered research on the functional genomics and potential improvements of H.cordata.In this study,we present a near-complete assembly of H.cordata genome and investigate the biosynthetic pathway of flavonoids,specifically quercetin,using genomics,transcriptomics,and metabolomics analyses.The genome of H.cordata diverged from that of Saururus chinensis around 33.4 million years ago;it consists of 2.24 Gb with 76 chromosomes(4n=76)and has undergone three whole-genome duplication(WGD)events.These WGDs played a crucial role in shaping the H.cordata genome and influencing the gene families associated with its medicinal properties.Through metabolomics and transcriptomics analyses,we identified key genes involved in the b-oxidation process for biosynthesis of houttuynin,one of the volatile oils responsible for the plant’s fishy smell.In addition,using the reference genome,we identified genes involved in flavonoid biosynthesis,particularly quercetin metabolism,in H.cordata.This discovery has important implications for understanding the regulatory mechanisms that underlie production of active pharmaceutical ingredients in traditional Chinese medicine.Overall,the high-quality genome assembly of H.cordata serves as a valuable resource for future functional genomics research and provides a solid foundation for genetic improvement of H.cordata for the benefit of human health.

Rescuing the Golgi from heat damages by ATG8:restoration rather than clean-up

High temperature stress poses significant adverse effects on crop yield and quality.Yet the molecular mechanisms underlying heat stress tolerance in plants/crops,especially regarding the organellar remodeling and homeostasis,are largely unknown.In a recent study,Zhou et al.reported that autophagy-related 8(ATG8),a famous regulator involved in autophagy,plays a new role in Golgi restoration upon heat stress.Golgi apparatus is vacuolated following short-term acute heat stress,and ATG8 is translocated to the dilated Golgi membrane and interacts with CLATHRIN LIGHT CHAIN 2(CLC2)to facilitate Golgi restoration,which is dependent on the ATG conjugation system,but not of the upstream autophagic initiators.These exciting findings broaden the fundamental role of ATG8,and elucidate the organelle-level restoration mechanism of Golgi upon heat stress in plants.

A Novel QTL qTGW3 Encodes the GSK3/ SHAGGY-Like Kinase OsGSK5/OsSK41 that Interacts with OsARF4 to Negatively Regulate Grain Size and Weight in Rice

Grain size and shape are important determinants of grain weight and yield in rice. Here, we report a new major quantitative trait locus （QTL）, qTGW3, that controls grain size and weight in rice. This locus, qTGW3, encodes OsSK41 （also known as OsGSK5）, a member of the GLYCOGEN SYNTHASE KINASE 3/SHAGGY-like family. Rice near-isogenic lines carrying the loss-of-function allele of OsSK41 have increased grain length and weight. We demonstrate that OsSK41 interacts with and phosphorylates AUXIN RESPONSE FACTOR 4 （OsARF4）. Co-expression of OsSK41 with OsARF4 increases the accumulation of OsARF4 in rice protoplasts. Loss of function of OsARF4 results in larger rice grains. RNA-sequencing analysis suggests that OsARF4 and OsSK41 repress the expression of a common set of downstream genes, including some auxin-responsive genes, during rice grain development. The loss-of-function form of OsSK41 at qTGW3 represents a rare allele that has not been extensively utilized in rice breeding. Suppression of OsSK41 function by either targeted gene editing or QTL pyramiding enhances rice grain size and weight. Thus, our study reveals the important role of OsSK41 in rice grain development and provides new candidate genes for genetic improvement of grain yield in rice and perhaps in other cereal crops.

Protein Quality Control in Plant Organelles:Current Progress and Future Perspectives

The endoplasmic reticulum,chloroplasts,and mitochondria are major plant organelles for protein synthesis,photosynthesis,metabolism,and energy production.Protein homeostasis in these organelles,maintained by a balance between protein synthesis and degradation,is essential for cell functions during plant growth,development,and stress resistance.Nucleus-encoded chloroplast-and mitochondrion-targeted proteins and ER-resident proteins are imported from the cytosol and undergo modification and maturation within their respective organelles.Protein folding is an error-prone process that is influenced by both developmental signals and environmental cues;a number of mechanisms have evolved to ensure efficient import and proper folding and maturation of proteins in plant organelles.Misfolded or damaged proteins with nonnative conformations are subject to degradation via complementary or competing pathways:intraorganelle proteases,the organelle-associated ubiquitin-proteasome system,and the selective autophagy of partial or entire organelles.When proteins in nonnative conformations accumulate,the organellespecific unfolded protein response operates to restore protein homeostasis by reducing protein folding demand,increasing protein folding capacity,and enhancing components involved in proteasome-associated protein degradation and autophagy.This review summarizes recent progress on the understanding of protein quality control in the ER,chloroplasts,and mitochondria in plants,with a focus on common mechanisms shared by these organelles during protein homeostasis.

Chromatin remodeling factors regulate environmental stress responses in plants

Environmental stress from climate change and agricultural activity threatens global plant biodiversity as well as crop yield and quality.As sessile organisms,plants must maintain the integrity of their genomes and adjust gene expression to adapt to various environmental changes.In eukaryotes,nucleosomes are the basic unit of chromatin around which genomic DNA is packaged by condensation.To enable dynamic access to packaged DNA,eukaryotes have evolved Snf2(sucrose nonfermenting 2)family proteins as chromatin remodeling factors(CHRs)that modulate the position of nucleosomes on chromatin.During plant stress responses,CHRs are recruited to specific genomic loci,where they regulate the distribution or composition of nucleosomes,which in turn alters the accessibility of these loci to general transcription or DNA damage repair machinery.Moreover,CHRs interplay with other epigenetic mechanisms,including DNA methylation,histone modifications,and deposition of histone variants.CHRs are also involved in RNA processing at the posttranscriptional level.In this review,we discuss major advances in our understanding of the mechanisms by which CHRs function during plants’response to environmental stress.

Cellulose synthesis genes CESA6 and CSI1 are important for salt stress tolerance in Arabidopsis

Soil salinity is a widespread abiotic stress constraint threatening agricultural production, as it severely inhibits growth and development of crops. Several salt stress signaling pathways have been discovered in the model plant Arabidopsis thaliana, which include components for sensing the stress, transmitting the signal and regulating the downstream genes （Deinlein et al. 2o14; Julkowska and Testerink 2015）. In nature, plant roots directly encounter heterogeneous soils and therefore their responses to saline environments require dynamic changes in growth, a process in which plant cell walls play important roles （Tenhaken 2o15）. However, the molecular mechanisms underlying cell wall remodeling under stress conditions are still unclear.

The E3 ligase XBAT35 mediates thermoresponsive hypocotyl growth by targeting ELF3 for degradation in Arabidopsis

Plants are capable of coordination of their growth and development with ambient temperatures.EARLY FLOWERING3(ELF3), an essential component of the plant circadian clock, is also involved in ambient temperature sensing, as well as in inhibiting the expression and protein activity of the thermoresponsive regulator phytochrome interacting factor4(PIF4). The ELF3 activity is subjected to attenuation in response to warm temperature;however,how the protein level of ELF3 is regulated at warm temperature remains less understood. Here, we report that the E3 ligase XB3 ORTHOLOG 5 IN ARABIDOPSIS THALIANA, XBAT35, mediates ELF3 degradation. XBAT35 interacts with ELF3 and ubiquitinates ELF3. Loss-of-function mutation of XBAT35 increases the protein level of ELF3 and confers a short-hypocotyl phenotype under warm temperature conditions. Thus, our findings establish that XBAT35 mediates ELF3 degradation to lift the inhibition of ELF3 on PIF4 for promoting thermoresponsive hypocotyl growth in plants.

Mutation of DELAYED GREENING1 impairs chloroplast RNA editing at elevated ambient temperature in Arabidopsis

Chloroplasts are important for plant growth and development.RNA editing in chloroplast converts cytidines(Cs)to uridine s(Us)at specific transcript positions and provides a correction mechanism to restore conserved codons or creates start or stop codons.However,the underlined molecular mechanism is not yet fully unders tood.In the present study,we identi fied a thermo-sensi tive mutantin leaf color 1(tst1)and found that TSL1 is allelic to DELAYED GREENING 1(DG1).The mis sense mutation of DG1 in tsl1 mutant confers a high temperature sensitivity and impaired chloroplast development at an elevated ambient temperature in Arabidopsis.Subsequent analysis showed that chloroplast RNA editing at seve ral sites including accD-2568,ndhD-2,and petL-5 is impaired in tsl1 mutant plants grown at an elevated temperature.DG1 interacts with MORF2 and other proteins such as DYW1 and DYW2 involved in chloroplast RNA editing.In vitro RNA electrophoretic mobility shift assay demonstrated that DG1 binds to RNA targets such as accD,ndhD,and petL.Thus,our results revealed that DG1 is important for maintaining chloroplast mRNA editing in Arabidopsis.

Reversible and Irreversible Drought-Induced Changes in the Anther Proteome of Rice （Oryza sativa L.） Genotypes IR64 and Moroberekan

Crop yield is most sensitive to water deficit during the reproductive stage. For rice, the most sensitive yield component is spikelet fertility and the most sensitive stage is immediately before heading. Here, we examined the effect of drought on the anther proteome of two rice genotypes： Moroberekan and IR64. Water was withheld for 3 d before head- ing （3DBH） in well watered controls for 5 d until ＂the flag leaf relative water content （RWC） had declined to 45-50%. Plants were then re-watered and heading occurred 2-3 d later, representing a delay of 4-5 d relative to controls. The anther proteins were separated at 3 DBH, at the end of the stress period, and at heading in stressed/re-watered plants and con- trols by two-dimensional （2-D） gel electrophoresis, and 93 protein spots were affected reproducibly in abundance by drought during the experiment across two rice genotypes. After drought stress, upon re-watering, expressions of 24 pro- tein spots were irreversible in both genotypes, 60 protein spots were irreversible in IR64 but reversible in Moroberekan, only nine protein spots were irreversible in Moroberekan while reversible in IR64. Among them, there were 14 newly drought-induced protein spots in IR64; none of them was reversible on re-watering. However, there were 13 newly drought-induced protein spots in Moroberekan, 10 of them were reversible on re-watering, including six drought-induced protein spots that were not reversed in IR64. Taken together, our proteomics data reveal that drought-tolerant genotype Moroberekan possessed better recovery capability following drought and re-watering at the anther proteome level than the drought-sensitive genotype IR64. The disruptions of drought to rice anther development and pollen cell functions are also discussed in the paper.

REVEILLE 7 inhibits the expression of the circadian clock gene EARLY FLOWERING 4 to fine-tune hypocotyl growth in response to warm temperatures

The circadian clock maintains the daily rhythms of plant growth and anticipates predictable ambient temperature cycles.The evening complex(EC),comprising EARLY FLOWERING 3(ELF3),ELF4,and LUX ARRHYTHMO,plays an essential role in suppressing thermoresponsive hypocotyl growth by negatively regulating PHYTOCHROME INTERACTING FACTOR 4(PIF4)activity and its downstream targets in Arabidopsis thaliana.However,how EC activity is attenuated by warm temperatures remains unclear.Here,we demonstrate that warm temperature-induced REVEILLE7(RVE7)fine-tunes thermoresponsive growth in Arabidopsis by repressing ELF4 expression.RVE7 transcript and RVE7 protein levels increased in response to warm temperatures.Under warm temperature conditions,an rve7 loss-of-function mutant had shorter hypocotyls,while overexpressing RVE7 promoted hypocotyl elongation.PIF4 accumulation and downstream transcriptional effects were reduced in the rve7 mutant but enhanced in RVE7 overexpression plants under warm conditions.RVE7 associates with the Evening Element in the ELF4 promoter and directly represses its transcription.ELF4 is epistatic to RVE7,and overexpressing ELF4 suppressed the phenotype of the RVE7 overexpression line under warm temperature conditions.Together,our results identify RVE7 as an important regulator of thermoresponsive growth that functions(in part)by controlling ELF4 transcription,highlighting the importance of ELF4 for thermomorphogenesis in plants.

UBA domain protein SUF1 interacts with NatA-complex subunit NAA15 to regulate thermotolerance in Arabidopsis

During recovery from heat stress,plants clear away the heat-stress-induced misfolded proteins through the ubiquitin-proteasome system(UPS).In the UPS,the recognition of substrate proteins by E3 ligase can be regulated by the N-terminal acetyltransferase A(NatA)complex.Here,we determined that Arabidopsis STRESS-RELATED UBIQUITIN-ASSOCIATED-DOMAIN PROTEIN FACTOR 1(SUF1)interacts with the NatA complex core subunit NAA15 and positively regulates NAA15.The suf1 and naa15 mutants are sensitive to heat stress;the NatA substrate NSNC1 is stabilized in suf1 mutant plants during heat stress recovery.Therefore,SUF1 and its interactor NAA15 play important roles in basal thermotolerance in Arabidopsis.

Bamboo leaf extract improves spatial learning ability in a rat model with senile dementia

Senile dementia（SD） is a syndrome characterized by progressive neurological deterioration. Treatment for the disease is still under investigation. Bamboo leaf extract（B-extract） has been known for its biological efficacy in anti-oxidant and anti-cancer activities. However, study on B-extract for its protection against dementia is very limited. The effect of B-extract on a rat model with SD was examined. B-extract improved spatial learning ability of the dementia rats. The hippocampus of dementia model rats showed reduced levels of acetylcholine（ACh）, epinephrine（E）, norepinephrine（NE）, and dopamine（DA）, and increased activities of acetylcholine esterase（ACh E） and monoamine oxidase（MAO）. Treatment with B-extract 20 mg/（kg·d） for 7 weeks significantly inhibited the enzyme activity compared with untreated dementia rats, and raised the levels of ACh, E, and DA in the hippocampus. In addition, treatment with B-extract elevated the level of γ-aminobutyric acid（GABA）, but reduced the level of glutamate（Glu） in the brain. These data suggest that B-extract might be a potential drug in treating impairment of spatial memory in dementia rats by regulating the central neurotransmitter function.

bZIP17 regulates heat stress tolerance at reproductive stage in Arabidopsis

High temperature elicits a well-conserved response called the unfol ded protein response(UPR)to bring protein homeostasis in the endoplasmic reticulum(ER).Two key UPR regulators bZIP28 and bZIP60 have been shown to be essential for maintaining fertility under heat stress conditions in Arabidopsis,however,the function of transcriptional activator bZIP17,a paralog of bZIP28,in heat stress response at reproductive stage is not reported.Here we found that bzip17 mutant plants were sensitive to heat stress in terms of silique length and fertility comparing to that of wildtype(WT)Arabidopsis plants,and transcri ptomic analysis showed that 1380 genes were specifically up-regulated and 493 genes were specifically down-regulated by heat stress in the flowers of WT plants comparing to that in bzip17 mutant plants.These bZIP17-dependent up-regulated genes were enriched in responses to a biotic stresses such as water deprivation and salt stress.Further chromatin immuno-preci pitation coupled with high-throughput sequencing(ChIP-Seq)uncovered 1645 genes that were direct targets of bZIP17 in MYC-bZIP17 expressing seedlings subjected to heat stress.Among these 1645 genes,ERSE-II cis-element was enriched in the binding peaks of their promoters,and the up-regulation of 113 genes by heat stress in flowers was dependent on bZIP17.Our results revealed direct targets of bZIP17 in flowers during heat stress responses and demonstrated the important role of bZIP17 in maintai ning fertility upon heat stress in plants.

Disruption of three polyamine uptake transporter genes in rice by CRISPR/Cas9 gene editing confers tolerance to herbicide paraquat

Weeds are a major biotic constraint that can cause dramatic crop production losses.Herbicide technology has been widely used by farmers as the most cost-effective weed control measure,and development of new strategy to improve herbicide tolerance in plants is urgently needed.The CRISPR/Cas9-based genome editing tool has been used in diverse applications related to agricultural technology for crop improvement.Here we identified three polyamine uptake transporter(PUT)genes in rice that are homologous to the Arabidopsis AtRMV1.We successfully demonstrate that CRISPR/Cas9-targeted mutagenesis of OsPUT1/2/3 greatly improves paraquat resistance in rice without obvious yield penalty.Therefore,manipulation of these loci could be valuable for producing transgene-free rice with improved herbicide resistance in future.

Roles of plant hormones in thermomorphogenesis

Global warming has great impacts on plant growth and development,as well as ecological distribution.Plants constantly perceive environmental temperatures and adjust their growth and development programs accordingly to cope with the environment under non-lethal warm temperature conditions.Plant hormones are endogenous bioactive chemicals that play central roles in plant growth,developmental,and responses to biotic and abiotic stresses.In this review,we summarize the important roles of plant hormones,including auxin,brassinosteroids(BRs),Gibberellins(GAs),ethylene(ET),and jasmonates(JAs),in regulating plant growth under warm temperature conditions.This provides a picture on how plants sense and transduce the warm temperature signals to regulate downstream gene expression for controlling plant growth under warm temperature conditions via hormone biosynthesis and signaling pathways.