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In order to improve the living standards of diabetes patients and reduce the negative health effects of this disease, the medical community has been actively searching for more effective treatments. In recent years, an artificial pancreas has emerged as an important approach to managing diabetes. Despite these recent advances, meeting the requirements for miniaturized size, accurate sensing and large-volume pumping capability remains a great challenge. Here, we present a novel miniaturized artificial pancreas based on a long microtube sensor integrated with an ultrasonic pump. Our device meets the requirements of achieving both accurate sensing and high pumping capacity. The artificial pancreas is constructed based on a long microtube that is low cost, painless and simple to operate, where the exterior of the microtube is fabricated as a glucose sensor for detecting diabetes and the interior of the microtube is used as a channel for delivering insulin through an ultrasonic pump. This work successfully achieved closed-loop control of blood glucose and treatment of diabetes in rats. It is expected that this work can open up new methodologies for the development of microsystems, and advance the management approach for diabetes patients. [Display omitted] • We report a miniature artificial pancreas with accuracy and high pumping capacity. • The artificial pancreas is based on a long microtube sensor and an ultrasonic pump. • This work realized a closed-loop control of blood glucose levels in diabetic rats. [ABSTRACT FROM AUTHOR]

The development of novel diabetes monitoring sensors is important for the diabetes management of millions of diabetic patients. This work reports a flexible filamentary continuous glucose monitoring (CGM) sensor. A multilayer CGM sensor has been constructed on titanium filament with low cost and ease of use. The sensor, made of flexible material, offers better adaptability and comfort than traditional rigid filament CGM sensors, allowing continuous monitoring of subcutaneous blood glucose levels to provide patients with treatment strategies. The performance and reliability of the sensor were verified through rat experiments. The trend of the increase and decrease of the detected current was generally consistent with the actual blood glucose, and the detected values were located in regions A and B of the Clarke error grid. The results show that the sensor has the advantages of high sensitivity, high accuracy and fast response speed, which is suitable for monitoring the blood glucose level for a long time and has a broad application prospect in diabetes monitoring, exercise monitoring, health management and clinical application. [Display omitted] • This work reports a flexible filamentary continuous glucose monitoring (CGM) sensor. • A multilayer CGM sensor has been constructed on titanium filament with low cost and ease of use. • The performance of the sensor was verified through rat experiments with high reliability and accuracy. • The sensor has high sensitivity, high accuracy and fast response for monitoring interstitial glucose. [ABSTRACT FROM AUTHOR]

As the rapid development of medical devices, micropumps have received increasing and widespread attentions for a variety of healthcare applications. The ongoing challenges for developing the micropumps for healthcare applications are the working mechanisms of the pumps, the device configurations, and the fabrication approaches. To address these challenges, this review would explore the fundamental principles and practical aspects of the micropumps, including the types of the micropumps, their working principles, the manufacturing processes for constructing the micropumps, and the related biomedical applications and commercial products. This review can serve as a resouce for the construction of next-generation micropumps, as well as a wide range of biomedical applications ranging from the disease diagnosis to drug delivery. [Display omitted] [ABSTRACT FROM AUTHOR]

The development of a simple directly wearable approach for the rapid, specific and sensitive determination of biomarkers is of great importance to a variety of biomedical applications. Dental floss can provide a unique device platform for sensing of oral biomarkers. We show here for the first time the development of a smart dental floss for biosensing of glucose. The sensor was made by painting carbon graphite ink and Ag/AgCl ink on dental floss. Via the immobilization of glucose oxidase, we show the detection of glucose with a detection range of 0.048 mM to 19.5 mM and a response time of about 2 min. It is expected that our results could provide new exciting opportunities for the development of various flexible smart sensing devices in oral health applications. [ABSTRACT FROM AUTHOR]

The development of new signal systems for electrical biosensors could provide exciting new opportunities for biomedical analysis, pollutant monitoring, and explosive detection. The signal systems for commercial portable sensors involve the integration of a battery and a circuit conditioning system to power an amperometric biosensor. However, this increases the size and complexity of the entire system. In this study, we develop a simple amperometric biosensor that is directly powered by a button cell battery for the detection of lactate. A two-electrode sensing transducer was printed on cardboard or integrated on a ring. It was directly powered by a button cell battery, and connected to a multimeter for current measurement. This sensor showed a sensitive detection range of 0.04762–9.21429 mM and short measuring time of 2 min. These results show that this system can achieve an excellent sensing performance, and the construction of this new sensing system directly powered by a button cell battery offers a new method for further developing a wide range of miniaturized, flexible, portable, or wearable sensing systems, and these could be used in detecting various analytes that are important in medical diagnosis and environmental monitoring. [ABSTRACT FROM AUTHOR]

In clinical practice, sera creatinine level is regarded as a crucial biomarker for the diagnosis, staging and monitoring of kidney disease. An amperometric biosensor is rapid, accurate, and cost-effective, with a portability and a simple operation. Herein, we report for the firsttime a disposable, printed amperometric biosensor for the clinical evaluation of creatinine in renal function detection. The sensor is constructed based on Prussian blue/carbon-graphite paste as the working electrode and the immobilization of creatinine amidohydrolase, creatine amidinohydrolase and sarcosine oxidase. The creatinine biosensor shows a linear detection range from 0.05 to 1.4 mM with a detection time of about 3 min. In addition, the sensor shows a high stability that can maintain above 86% of the initial activity after being stored for over 4 months. Moreover, the sensor shows almost the same results as those with the Jaffe method for measuring the real blood samples. We anticipate that the creatinine biosensor could be widely used in the medical and healthcare areas, especially for at-home testing and onsite medical examinations. [Display omitted] • The work reports for the first time the development of a disposable, miniaturized and cost-effective creatinine biosensor. • The biosensor shows an accurate, sensitive and rapid determination of serum creatinine in renal function detection. • The biosensor demonstrates a similar detection performance to the Jeff Method that is used in hospital. • The biosensor exhibits a great potential for the at-home testing and the on-site medical examination. [ABSTRACT FROM AUTHOR]

Uric acid and creatinine are essential biomarkers for many diseases, such as gout, hyperuricemia, kidney diseases and heart diseases. Electrochemical biosensors are promising candidates for detecting uric acid and creatinine. However, the sensors always suffer from low stability that would limit their practical applications. In this work, we report a new multilayer enzyme matrix to enhance the room-temperature storage stabilities of uric acid and creatinine biosensors significantly. The enzymes are first dropped on the electrode surface directly, then a layer of glutaraldehyde was deposited on the surface of the enzyme layer, and after that, another layer of a polyvinyl alcohol (PVA)/poly(ethylene glycol) (PEG) composite was further placed on the surface of the glutaraldehyde layer, with drying in between. The stabilities of uric acid and creatinine biosensors were enhanced significantly, and the sensors can maintain highly stable sensing performance for over 4 months with a storage at room temperature. It is anticipated that this work could open new avenues for the practical applications of the uric acid and creatinine biosensors. [Display omitted] • The work reports a new multilayer enzyme matrix to enhance the room-temperature storage stabilities of biosensors. • The method is based on a sequential deposition of enzyme, glutaraldehyde, and polyvinyl alcohol/poly(ethylene glycol). • The sensors can maintain highly stable sensing performance for over 4 months with a storage at room temperature. • The sensors can perform accurate detection of uric acid and creatinine in whole blood samples. [ABSTRACT FROM AUTHOR]

Abstract: Many rice breeding programs have currently reached yield plateaus as a result of limited genetic variability in parental strains. Dongxiang common wild rice (Oryza rufipogon Griff.) is the progenitor of cultivated rice (Oryza sativa L.) and serves as an important gene pool for the genetic improvement of rice cultivars. In this study, heterotic loci (HLs) associated with six yield-related traits were identified in wild and cultivated rice and investigated using a set of 265 introgression lines (ILs) of O. rufipogon Griff. in the background of the Indica high-yielding cultivar Guichao 2 (O. sativa L.). Forty-two HLs were detected by a single point analysis of mid-parent heterosis values from test cross F1 offspring, and 30 (71.5%) of these HLs showed significantly positive effects, consistent with the superiority shown by the F1 test cross population in the six yield-related traits under study. Genetic mapping of hsp11, a locus responsible for the number of spikelets per panicle, confirmed the utility of these HLs. The results indicate that favorable HLs capable of improving agronomic traits are available. The identification of HLs between wild rice and cultivated rice could lead to a new strategy for the application of heterosis in rice breeding. [Copyright &y& Elsevier]

In rice ( Oryza sativa L.), the number of panicles, spikelets per panicle and grain weight are important components of grain yield. These characteristics are controlled by quantitative trait loci (QTLs) and are derived from variation inherent in crops. As a result of the complex genetic basis of these traits, only a few genes involved in their control have been cloned and characterized. We have previously map-cloned a gene cluster including eight leucine-rich repeat receptor-like kinase ( LRK) genes in Dongxiang wild rice ( Oryza rufipogon Griff.), which increased the grain yield by 16%. In the present study, we characterized the LRK1 gene, which was contained in the donor parent (Dongxiang wild rice) genome and absent from the recurrent parent genome (Guichao2, Oryza sativa L. ssp. indica). Our data showed that rice LRK1 is a plasma membrane protein expressed constitutively in leaves, young panicles, roots and culms. The over-expression of rice LRK1 results in increased panicles, spikelets per panicle, weight per grain and enhanced cellular proliferation, leading to a 27.09% increase in total grain yield per plant. The increased number of panicles and spikelets per panicle are associated with increased branch number. Our data suggest that rice LRK1 regulates rice branch number by enhancing cellular proliferation. The functional characterization of rice LRK1 facilitates an understanding of the mechanisms involved in cereal crop yield, and may have utility in improving grain yield in cereal crops. [ABSTRACT FROM AUTHOR]

A set of 148 F9 recombinant inbred lines (RILs) was developed from the cross of an indica cultivar 93-11 and japonica cultivar DT713, showing strong F1 heterosis. Subsequently, two backcross F1 (BCF1) populations were constructed by backcrossing these 148 RILs to two parents, 93-11 and DT713. These three related populations (281BCF1 lines, 148 RILs) were phenotyped for six yield-related traits in two locations. Significant inbreeding depression was detected in the population of RILS and a high level of heterosis was observed in the two BCF1 populations. A total of 42 main-effect quantitative trait loci (M-QTLs) and 109 epistatic effect QTL pairs (E-QTLs) were detected in the three related populations using the mixed model approach. By comparing the genetic effects of these QTLs detected in the RILs, BCF1 performance and mid-parental heterosis ( HMP), we found that, in both BCF1 populations, the QTLs detected could be classified into two predominant types: additive and over-dominant loci, which indicated that the additive and over-dominant effect were more important than complete or partially dominance for M-QTLs and E-QTLs. Further, we found that the E-QTLs detected collectively explained a larger portion of the total phenotypic variation than the M-QTLs in both RILs and BCF1 populations. All of these results suggest that additive and over-dominance resulting from epistatic loci might be the primary genetic basis of heterosis in rice. [ABSTRACT FROM AUTHOR]

Background: Yield and quality are the two most important traits in crop breeding. Exploring the regulatory mechanisms that affect both yield and quality traits is of great significance for understanding the molecular genetic networks controlling these key crop attributes. Expansins are cell wall loosening proteins that play important roles in regulating rice grain size. Results: We investigated the effect of OsEXPA7, encoding an expansin, on rice grain size and quality. OsEXPA7 overexpression resulted in increased plant height, panicle length, grain length, and thousand-grain weight in rice. OsEXPA7 overexpression also affected gel consistency and amylose content in rice grains, thus affecting rice quality. Subcellular localization and tissue expression analyses showed that OsEXPA7 is localized on the cell wall and is highly expressed in the panicle. Hormone treatment experiments revealed that OsEXPA7 expression mainly responds to methyl jasmonate, brassinolide, and gibberellin. Transcriptome analysis and RT-qPCR experiments showed that overexpression of OsEXPA7 affects the expression of OsJAZs in the jasmonic acid pathway and BZR1 and GE in the brassinosteroid pathway. In addition, OsEXPA7 regulates the expression of key quantitative trait loci related to yield traits, as well as regulates the expression levels of BIP1 and bZIP50 involved in the seed storage protein biosynthesis pathway. Conclusions: These results reveal that OsEXPA7 positively regulates rice yield traits and negatively regulates grain quality traits by involving plant hormone pathways and other trait-related pathway genes. These findings increase our understanding of the potential mechanism of expansins in regulating rice yield and quality traits and will be useful for breeding high-yielding and high-quality rice cultivars. [ABSTRACT FROM AUTHOR]

Objective: This study aims to perform a prenatal genetic diagnosis of a high-risk fetus with trisomy 7 identified by noninvasive prenatal testing (NIPT) and to evaluate the efficacy of different genetic testing techniques for prenatal diagnosis of trisomy mosaicism. Methods: For prenatal diagnosis of a pregnant woman with a high risk of trisomy 7 suggested by NIPT, karyotyping and chromosomal microarray analysis (CMA) were performed on an amniotic fluid sample. Low-depth whole-genome copy number variation sequencing (CNV-seq) and fluorescence in situ hybridization (FISH) were used to clarify the results further. In addition, methylation-specific multiplex ligation-dependent probe amplification (MS-MLPA) was performed to analyze the possibility of uniparental disomy(UPD). Results: Amniotic fluid karyotype analysis revealed a 46, XX result. Approximately 20% mosaic trisomy 7 was detected according to the CMA result. About 16% and 4% of mosaicism was detected by CNV-seq and FISH, respectively. MS-MLPA showed no methylation abnormalities. The fetal ultrasound did not show any detectable abnormalities except for mild intrauterine growth retardation seen at 39 weeks of gestation. After receiving genetic counseling, the expectant mother decided to continue the pregnancy, and follow-up within three months of delivery was normal. Conclusion: In high-risk NIPT diagnosis, a combination of cytogenetic and molecular genetic techniques proves fruitful in detecting low-level mosaicism. Furthermore, the exclusion of UPD on chromosome 7 remains crucial when NIPT indicates a positive prenatal diagnosis of trisomy 7. [ABSTRACT FROM AUTHOR]

The development of new bioelectronic platforms for direct interactions with oral fluid could open up significant opportunities for healthcare monitoring. A tongue depressor is a widely used medical tool that is inserted into the mouth, where it comes into close contact with saliva. Glucose is a typical salivary biomarker. Herein, we report—for the first time—a tongue depressor-based biosensor for the detection of glucose in both phosphate buffer and real human saliva. Carbon nanotubes (CNTs) are attractive electronic materials, with excellent electrochemical properties. The sensor is constructed by printing CNTs and silver/silver chloride (Ag/AgCl) to form three electrodes in an electrochemical cell: Working, reference, and counter electrodes. The enzyme glucose oxidase (GOD) is immobilized on the working electrode. The glucose detection performance of the sensor is excellent, with a detection range of 7.3 μM to 6 mM. The glucose detection time is about 3 min. The discretion between healthy people's and simulated diabetic patients' salivary samples is clear and easy to tell. We anticipate that the biosensor could open up new opportunities for the monitoring of salivary biomarkers and advance healthcare applications. [ABSTRACT FROM AUTHOR]

Objective: To investigate factors associated with fetal fraction and to develop a new predictive method for low fetal fraction before noninvasive prenatal testing. Methods: The study was a retrospective cohort analysis based on the results of noninvasive prenatal testing, complete blood count, thyroxin test, and Down's syndrome screening during the first or second trimester in 14,043 pregnant women. Random forests algorithm was applied to predict the low fetal fraction status (fetal fraction < 4%) through individual information and laboratory records. The performance of the model was evaluated and compared to predictions using maternal weight. Results: Of 14,043 cases, maternal weight, red blood cell, hemoglobin, and free T3 were significantly negatively correlated with fetal fraction while gestation age, free T4, pregnancy-associated plasma protein-A, alpha-fetoprotein, unconjugated estriol, and β-human chorionic gonadotropin were significantly positively correlated with fetal fraction. Compared to predictions using maternal weight as an isolated parameter, the model had a higher area under the curve of receiver operating characteristic and overall accuracy. Conclusions: The comprehensive predictive method based on combined multiple factors was more effective than a single-factor model in low fetal fraction status prediction. This method can provide more pretest quality control for noninvasive prenatal testing. [ABSTRACT FROM AUTHOR]

RNA‐binding proteins (RBPs) are components of the post‐transcriptional regulatory system, but their regulatory effects on complex traits remain unknown. Using an integrated strategy involving map‐based cloning, functional characterizations, and transcriptomic and population genomic analyses, we revealed that RBP‐K (LOC_Os08g23120), RBP‐A (LOC_Os11g41890), and RBP‐J (LOC_Os10g33230) encode proteins that form an RBP‐A‐J‐K complex that negatively regulates rice yield‐related traits. Examinations of the RBP‐A‐J‐K complex indicated RBP‐K functions as a relatively non‐specific RBP chaperone that enables RBP‐A and RBP‐J to function normally. Additionally, RBP‐J most likely affects GA pathways, resulting in considerable increases in grain and panicle lengths, but decreases in grain width and thickness. In contrast, RBP‐A negatively regulates the expression of genes most likely involved in auxin‐regulated pathways controlling cell wall elongation and carbohydrate transport, with substantial effects on the rice grain filling process as well as grain length and weight. Evolutionarily, RBP‐K is relatively ancient and highly conserved, whereas RBP‐J and RBP‐A are more diverse. Thus, the RBP‐A‐J‐K complex may represent a typical functional model for many RBPs and protein complexes that function at transcriptional and post‐transcriptional levels in plants and animals for increased functional consistency, efficiency, and versatility, as well as increased evolutionary potential. Our results clearly demonstrate the importance of RBP‐mediated post‐transcriptional regulation for the diversity of complex traits. Furthermore, rice grain yield and quality may be enhanced by introducing various complete or partial loss‐of‐function mutations to specific RBP genes using clustered regularly interspaced palindromic repeats (CRISPR)/CRISPR‐associated protein 9 technology and by exploiting desirable natural tri‐genic allelic combinations at the loci encoding the components of the RBP‐A‐J‐K complex through marker‐assisted selection. [ABSTRACT FROM AUTHOR]

Developing a simple and direct approach for interfacing a sensor and a target analyte is of great interest for fields such as medical diagnosis, threat detection, food quality control, and environmental monitoring. Gloves provide a unique interface for sensing applications. Here, we show for the first time the development of wearable carbon nanotube (CNT)-based amperometric biosensors painted onto gloves as a new sensing platform, used here for the determination of lactate. Three sensor types were studied, configured as: two CNT electrodes; one CNT electrode, and an Ag/AgCl electrode, and two CNT electrodes and an Ag/AgCl electrode. The sensors are constructed by painting the electrodes using CNT or Ag/AgCl inks. By immobilizing lactate oxidase onto the CNT-based working electrodes, the sensors show sensitive detections of lactate. Comparison of sensor performance shows that a combination of CNT and Ag/AgCl is necessary for highly sensitive detection. We anticipate that these findings could open exciting avenues for fundamental studies of wearable bioelectronics, as well as practical applications in fields such as healthcare and defense. [ABSTRACT FROM AUTHOR]

Objective: To investigate factors associated with fetal fraction and to develop a new predictive method for low fetal fraction before noninvasive prenatal testing. Methods: The study was a retrospective cohort analysis based on the results of noninvasive prenatal testing, complete blood count, thyroxin test, and Down's syndrome screening during the first or second trimester in 14,043 pregnant women. Random forests algorithm was applied to predict the low fetal fraction status (fetal fraction < 4%) through individual information and laboratory records. The performance of the model was evaluated and compared to predictions using maternal weight. Results: Of 14,043 cases, maternal weight, red blood cell, hemoglobin, and free T3 were significantly negatively correlated with fetal fraction while gestation age, free T4, pregnancy-associated plasma protein-A, alpha-fetoprotein, unconjugated estriol, and β-human chorionic gonadotropin were significantly positively correlated with fetal fraction. Compared to predictions using maternal weight as an isolated parameter, the model had a higher area under the curve of receiver operating characteristic and overall accuracy. Conclusions: The comprehensive predictive method based on combined multiple factors was more effective than a single-factor model in low fetal fraction status prediction. This method can provide more pretest quality control for noninvasive prenatal testing. [ABSTRACT FROM AUTHOR]

Developing a simple and direct approach for sensitive, specific, and rapid detection of metabolic compounds is of great importance for a variety of biological, medical, and food applications. Tubes are a highly portable and accessible container shape which are widely used for scientific research in cell biology and chemical synthesis, and which are also of great use in domestic health care applications. Here, we show for the first time the development of a tube-based painted amperometric biosensor for the detection of glucose and lactate. The sensor was prepared by printing carbon graphite and silver/silver chloride inks on the interior wall of the tube and then immobilizing glucose oxidase or lactate oxidase on the sensor. The sensor showed a sensitive, rapid, and reliable detection of glucose and lactate. We anticipate that these results could open new avenues for the development of painted biosensors, and toward advanced biosensor applications. [ABSTRACT FROM AUTHOR]

Amylose content (AC) is the main factor determining the palatability, viscosity, transparency, and digestibility of rice (Oryza sativa) grains. AC in rice grains is mainly controlled by different alleles of the Waxy (Wx) gene. The AP2/EREBP transcription factor OsEBP89 interacts with the MYC‐like protein OsBP5 to synergistically regulate the expression of Wx. Here, we determined that the GLYCOGEN SYNTHASE KINASE 5 (OsGSK5, also named SHAGGY‐like kinase 41 [OsSK41]) inhibits the transcriptional activation activity of OsEBP89 in rice grains during amylose biosynthesis. The loss of OsSK41 function enhanced Wx expression and increased AC in rice grains. By contrast, the loss of function of OsEBP89 reduced Wx expression and decreased AC in rice grains. OsSK41 interacts with OsEBP89 and phosphorylates four of its sites (Thr‐28, Thr‐30, Ser‐238, and Thr‐257), which makes OsEBP89 unstable and attenuates its interaction with OsBP5. Wx promoter activity was relatively weak when regulated by the phosphomimic variant OsEBP89E–OsBP5 but relatively strong when regulated by the nonphosphorylatable variant OsEBP89A–OsBP5. Therefore, OsSK41‐mediated phosphorylation of OsEBP89 represents an additional layer of complexity in the regulation of amylose biosynthesis during rice grain development. In addition, our findings provide four possible sites for regulating rice grain AC via precise gene editing. [ABSTRACT FROM AUTHOR]

Heading date is an important agronomic trait in rice (Oryza sativa L.). We previously fine‐mapped two complementary genes, Late Heading Date 1 and Late Heading Date 2 (LH2), that control the late heading trait in rice. Here, we cloned and analyzed the function of LH2. LH2 was fine‐mapped to a 53‐kb genomic region. Sequencing analysis revealed that there were differences in the coding sequence of LOC_Os08g07740 between the varieties 'Bo B' and 'Yuefeng B'. Therefore, LOC_Os08g07740 was identified as a candidate gene for LH2 and subsequently determined that LH2 is a Type 3 allele of Days To Heading 8. Transgenic plants of Yuefeng B carrying LH2 from Bo B significantly delayed the heading date under short‐day and long‐day conditions. A yeast two‐hybrid analysis revealed that LH2 physically interacted with Heme Activator Protein (HAP) 5A, ‐H, ‐I, ‐L, ‐K, and HAP5‐LIKE. The HAP5 domain of HAP5 family members has various functions. Further analysis revealed that LH2 represses photoperiodic flowering by controlling the expression of Early Heading Date 1, Heading date 3a, and Rice Flowering Locus T1 in rice. Core Ideas: LH2 delayed heading by 17.6 d in short‐day conditions and >32.7 d in long‐day conditions.LH2 physically interacted with HAP5A, ‐H, ‐I, ‐L, ‐K, and HAP5‐LIKE.The HAP5 domain of the HAP5 family exhibited functional differentiation.LH2 is a Type 3 allele of DTH8. [ABSTRACT FROM AUTHOR]

Background: Down syndrome (DS) is a chromosomal disorder caused by a third copy of all or part of chromosome 21. Clinical observations and preclinical studies both suggest that DS may be associated with significant metabolic and bioenergetic alterations. But the metabolic alterations in pregnant women carrying DS fetuses still remains unclear. In this study, we investigated the characteristic metabolomics and lipidomics changes during fetal development of DS.Methods: The AF and random urine specimens were selected from 20 pregnant women carrying DS fetuses and 20 pregnant women carrying healthy fetuses. The diagnosis of DS was screened according to chromosome karyotype analysis, and untargeted metabolomic and lipidomic analyses were performed.Results: Through the analyses of AF, 308 differential metabolites were selected between DS and controls. The metabolites with significant changes mainly involved lipid molecules, organic acids, nucleotides and carbon. Further analysis of lipidomics showed 64 differential metabolites, mainly involving glycerides, sphingolipids and glycerolipids. As for urine metabolomic and lipidomic analyses, there existed consistent metabolites with AF, but the number was much less.Conclusions: Compared with the controls, carbon metabolism, amino acid metabolism, glyceride metabolism, sphingolipid metabolism and glycerophospholipid metabolism were significantly changed in DS cases. In addition, characterized biomarkers in AF and urine were screened for DS diagnosis, and these metabolites were mainly involved in energy metabolism and liver dysfunction. This finding may help improve the efficiency of prenatal screening for DS. [ABSTRACT FROM AUTHOR]

Leaf‐color mutants have been extensively studied in rice (Oryza sativa L.) and many corresponding genes have been identified and cloned. However, the mechanism of complex leaf‐color mutations requires further study. In this study, we obtained an introgression line (TIL22) from a set of introgression lines raised using African cultivated rice (O. glaberrima Steud.) as the donor parent and O. sativa subsp. indica Teqing as the recipient. Compared with Teqing, TIL22 showed a yellow‐green leaf phenotype at the seedling stage, but the leaves gradually changed to green after the five‐leaf stage. The photosynthetic pigment contents of yellow‐green leaves at the seedling stage were significantly reduced and chloroplast development was retarded compared with those of Teqing. Genetic analysis indicated that the introgression line phenotype was controlled by a single nuclear gene, temporarily designated YGL22. Map‐based cloning and sequence analysis suggested that the candidate gene was likely to be LOC_Os01g15390, which encodes a chloroplast protein. Real‐time quantitative polymerase chain reaction (qPCR) analysis revealed that the YGL22 transcript level was significantly lower in TIL22 than that of Teqing at the seedling stage. We generated the ygl22 knockout mutant using the CRISPR/Cas9 system. The ygl22 mutants showed a similar phenotype to that of TIL22 at the seedling stage, suggesting that YGL22 may be involved in the early development of chloroplasts in rice. In addition, plant height, number of panicles per plant, and grain yield per plant of ygl22 were not significantly affected. The results indicate that YGL22 can be used as a trait marker gene in hybrid rice production. [ABSTRACT FROM AUTHOR]

Background: Noninvasive prenatal testing (NIPT) is commonly used to screen for fetal genetic abnormalities. However, the ability of NIPT to detect copy number variations (CNVs) has not been reported. Accordingly, in this study, we analyzed the efficiency of NIPT for the detection of fetal autosomal CNVs. Methods: Patients who were positive for autosomal CNVs by NIPT and underwent diagnostic studies by karyotype analysis and chromosomal microarray (CMA) were evaluated. Samples were divided into groups according to age, in vitro fertilization, fetal‐free DNA concentration, uniquely mapped reads number, CNV size, and CNV type. Results: Chromosomal microarray showed that the positive predictive value (PPV) of autosomal CNVs detected by NIPT was 14.89%. Increasing fetal DNA concentrations and uniquely mapped read numbers did not affect the PPV of CNVs detected by NIPT. There were no differences between microduplication and microdeletion PPVs detected by NIPT. The PPV of CNVs less than 10 Mb was significantly higher than that of CNVs greater than 10 Mb detected by NIPT. Conclusion: The accuracy of NIPT for autosomal CNVs needs to be improved. [ABSTRACT FROM AUTHOR]

Heading date is one of the most important traits in rice and regulated by multiple genes. Common wild rice is the ancestor of Asian cultivated rice and harbours abundant genetic diversity. To use wild rice resource in rice breeding, a set of 154 introgression lines (ILs) covering 93% of the genome of Jinghong common wild rice was constructed in the background 'Teqing', using 208 simple sequence repeat markers evenly distributed on 12 chromosomes. Among the ILs, the line JIL64 displayed late heading independent of photoperiod. Genetic analysis using the two F2 populations crossed ''Teqing'/JIL64 and JIL64/'Teqing' revealed that late flowering was controlled by a recessive gene on chromosome 8 (designated early heading date 8, ehd8), and ehd8 was fine mapped to the 50‐kb region flanked by markers RM22221 and 64Indel4. Sequencing and qRT‐PCR demonstrated that LOC_Os08g01410 and LOC_Os08g01420 were deleted in JIL64 and may be associated with the late heading of Jinghong common wild rice. These findings lay a practical foundation for characterizing ehd8, and the ILs help to mine genes from Jinghong common wild rice. [ABSTRACT FROM AUTHOR]

Grain size and shape are important determinants of grain weight and yield in rice. Here, we report a new major quantitative trait locus (QTL), q TGW3 , that controls grain size and weight in rice. This locus, q TGW3 , 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 Os SK41 have increased grain length and weight. We demonstrate that OsSK41 interacts with and phosphorylates AUXIN RESPONSE FACTOR 4 (OsARF4). Co-expression of Os SK41 with Os ARF4 increases the accumulation of OsARF4 in rice protoplasts. Loss of function of Os ARF4 results in larger rice grains. RNA-sequencing analysis suggests that Os ARF4 and Os SK41 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 Os SK41 at q TGW3 represents a rare allele that has not been extensively utilized in rice breeding. Suppression of Os SK41 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. [ABSTRACT FROM AUTHOR]

Developing methods for increasing the biomass and improving the plant architecture is important for crop improvement. We herein describe a gene belonging to the RING_Ubox (RING (Really Interesting New Gene) finger domain and U-box domain) superfamily, PLANT ARCHITECTURE and GRAIN NUMBER 1 (PAGN1), which regulates the number of grains per panicle, the plant height, and the number of tillers. We used the CRISPR/Cas9 system to introduce loss-of-function mutations to OsPAGN1. Compared with the control plants, the resulting pagn1 mutant plants had a higher grain yield because of increases in the plant height and in the number of tillers and grains per panicle. Thus, OsPAGN1 may be useful for the genetic improvement of plant architecture and yield. An examination of evolutionary relationships revealed that OsPAGN1 is highly conserved in rice. We demonstrated that OsPAGN1 can interact directly with OsCNR10 (CELL NUMBER REGULATOR10), which negatively regulates the number of rice grains per panicle. A transcriptome analysis indicated that silencing OsPAGN1 affects the levels of active cytokinins in rice. Therefore, our findings have clarified the OsPAGN1 functions related to rice growth and grain development. [ABSTRACT FROM AUTHOR]

Common wild rice ( Oryza rufipogon Griff.) is an important genetic reservoir for rice improvement. We investigated a quantitative trait locus (QTL), qGP5-1, which is related to plant height, leaf size and panicle architecture, using a set of introgression lines of O. rufipogon in the background of the Indica cultivar Guichao2 ( Oryza sativa L.). We cloned and characterized qGP5-1 and confirmed that the newly identified gene OsEBS (enhancing biomass and spikelet number) increased plant height, leaf size and spikelet number per panicle, leading to an increase in total grain yield per plant. Our results showed that the increased size of vegetative organs in OsEBS-expressed plants was enormously caused by increasing cell number. Sequence alignment showed that OsEBS protein contains a region with high similarity to the N-terminal conserved ATPase domain of Hsp70, but it lacks the C-terminal regions of the peptide-binding domain and the C-terminal lid. More results indicated that OsEBS gene did not have typical characteristics of Hsp70 in this study. Furthermore, Arabidopsis ( Arabidopsis thaliana) transformed with OsEBS showed a similar phenotype to OsEBS-transgenic rice, indicating a conserved function of OsEBS among plant species. Together, we report the cloning and characterization of OsEBS, a new QTL that controls rice biomass and spikelet number, through map-based cloning, and it may have utility in improving grain yield in rice. [ABSTRACT FROM AUTHOR]

Environmental stresses influence the growth of plants and the productivity of crops. Salinity is one of the most important abiotic stresses for agricultural crops. Programmed cell death (PCD) is induced by a variety of biotic and abiotic stresses in plants, including high salinity treatment. OsPDCD5, an ortholog of the mammalian-programmed cell death 5 gene, is up-regulated under low temperature and salt treatments in rice ( Oryza sativa). In this study, transgenic rice that constitutively expressed antisense- OsPDCD5 increased salt stress tolerance in unique ways by inhibiting PCD pathways and regulating specific groups of stress-related genes. Real-time quantitative PCR analysis showed that PCD pathways were inhibited under both normal conditions and salt stress in transgenic rice. Using transcript microarray analysis, 38 stress-related genes regulated in transgenic rice were identified, which appeared to render the transgenic rice adapted for salt stress conditions. Our results suggested that PCD pathways were inhibited and salt stress signaling pathways were regulated in transgenic rice even under normal growth conditions without stress. PCD was further inhibited and these stress-related genes were further regulated to increase tolerance to high salinity under salt stress conditions, thereby leading to build-up of stress protection mechanisms in transgenic rice. [ABSTRACT FROM AUTHOR]

A thorough understanding of the genetic basis of rice grain traits is critical for the improvement of rice ( Oryza sativa L.) varieties. In this study, we generated an F2 population by crossing the large-grain japonica cultivar CW23 with Peiai 64 (PA64), an elite indica small-grain cultivar. Using QTL analysis, 17 QTLs for five grain traits were detected on four different chromosomes. Eight of the QTLs were newly-identified in this study. In particular, qGL3-1, a newly-identified grain length QTL with the highest LOD value and largest phenotypic variation, was fine-mapped to the 17 kb region of chromosome 3. A serine/threonine protein phosphatase gene encoding a repeat domain containing two Kelch motifs was identified as the unique candidate gene corresponding to this QTL. A comparison of PA64 and CW23 sequences revealed a single nucleotide substitution (C→A) at position 1092 in exon 10, resulting in replacement of Asp (D) in PA64 with Glu (E) in CW23 for the 364th amino acid. This variation is located at the D position of the conserved sequence motif AVLDT of the Kelch repeat. Genetic analysis of a near-isogenic line (NIL) for qGL3-1 revealed that the allele qGL3-1 from CW23 has an additive or partly dominant effect, and is suitable for use in molecular marker-assisted selection. [ABSTRACT FROM AUTHOR]

With 4 figures and 1 table Abstract Oilseed rape ( Brassica napus L.) is the second most important oilseed crop in the world, and greater production of rape oil is required to satisfy the growing demand for it. We previously found that the cell size and yield of rice ( Oryza sativa) and cotton can be increased by over-expression of the RNA-binding domains (RRMs) of the flowering control locus A (FCA) protein. We also found that B. napus FCA-RRM2 shares a high level of sequence similarity with the RRM2 domains of other plants. We isolated B. napus FCA-RRM2 from variety No.1 'Nannongyou' of Brassica napus. Transformation experiments demonstrated that over-expression of B. napus FCA-RRM2 increases plant size, organ size, cell size, plant productivity and oil content in transgenic rape plants by down-regulating the cell-cycle-related gene cyclin-B2-1, a known activator of cyclin-dependent kinase 1 at the G2/M boundary. These results provide a practical approach for the genetic improvement of B. napus and possibly provide a model for investigating cell size regulation. [ABSTRACT FROM AUTHOR]

Allelic expression of the rice yield-related gene, leucine-rich receptor-like kinase 6 (LRK6), in the hybrid of 93-11 (Oryza sativa L. subsp. Indica var. 93-11) and Nipponbare (O. sativa L. subsp. Japonica var. Nipponbare) is determined by allelic promoter cis-elements. Using deletion analysis of the LRK6 promoter, we identified two distinct regions that might contribute to LRK6 expression. Sequence alignment revealed differences in these LRK6 promoter regions in 93-11 and Nipponbare. One of the segments, named differential sequence of LRK6 promoter 2 (DSLP2), contains potential transcription factor binding sites. Using a yeast one-hybrid assay, we isolated an ethylene-responsive factor (ERF) protein that binds to DSLP2. Sequence analysis and a GCC-box assay showed that the ERF gene, O. sativa ERF 3 (OsERF3), which belongs to ERF subfamily class II, has a conserved ERF domain and an ERF-associated amphiphilic repression repressor motif. We used an in vivo mutation assay to identify a new motif (5′-TAA(A)GT-3′) located in DSLP2, which interacts with OsERF3. These results suggest that OsERF3, an AP2 (APETALA 2 Gene)/ERF transcription factor, binds the LRK6 promoter at this new motif, which might cause differential expression of LRK6 in the 93-11/Nipponbare hybrid. [ABSTRACT FROM PUBLISHER]

A dwarf mutant, designated LB4D, was obtained among the progeny of backcrosses to a wild rice introgression line. Genetic analysis of LB4D indicated that the dwarf phenotype was controlled by a single semidominant dwarfing gene, which was named LB4D. The mutants were categorized as dn‐type dwarf mutants according to the pattern of internode reduction. In addition, gibberellin (GA) response tests showed that LB4D plants were neither deficient nor insensitive to GA. This study found that tiller formation by LB4D plants was decreased by 40% compared with the wild type, in contrast to other dominant dwarf mutants that have been identified, indicating that a different dwarfing mechanism might be involved in the LB4D dominant mutant. The reduction of plant height in F1 plants ranged from 27.9% to 38.1% in different genetic backgrounds, showing that LB4D exerted a stronger dominant dwarfing effect. Using large F2 and F3 populations derived from a cross between heterozygous LB4D and the japonica cultivar Nipponbare, the LB4D gene was localized to a 46 kb region between the markers Indel 4 and Indel G on the short arm of chromosome 11, and four predicted genes were identified as candidates in the target region. [ABSTRACT FROM AUTHOR]