The miR396-GRFs Module Mediates the Prevention of Photo-oxidative Damage by Brassinosteroids during Seedling De-Etiolation in Arabidopsis.

The switch from dark- to light-mediated development is critical for the survival and growth of seedlings, but the underlying regulatory mechanisms are incomplete. Here, we show that the steroids phytohormone brassinosteroids play crucial roles during this developmental transition by regulating chlorophyll biosynthesis to promote greening of etiolated seedlings upon light exposure. Etiolated seedlings of the brassinosteroids-deficient det2-1 (de-etiolated2) mutant accumulated excess protochlorophyllide, resulting in photo-oxidative damage upon exposure to light. Conversely, the gain-of-function mutant bzr1-1D (brassinazole-resistant 1-1D) suppressed the protochlorophyllide accumulation of det2-1, thereby promoting greening of etiolated seedlings. Genetic analysis indicated that phytochrome-interacting factors (PIFs) were required for BZR1-mediated seedling greening. Furthermore, we reveal that GROWTH REGULATING FACTOR 7 (GRF7) and GRF8 are induced by BZR1 and PIF4 to repress chlorophyll biosynthesis and promote seedling greening. Suppression of GRFs function by overexpressing microRNA396a caused an accumulation of protochlorophyllide in the dark and severe photobleaching upon light exposure. Additionally, BZR1, PIF4, and GRF7 interact with each other and precisely regulate the expression of chlorophyll biosynthetic genes. Our findings reveal an essential role for BRs in promoting seedling development and survival during the initial emergence of seedlings from subterranean darkness into sunlight.

Inheritance and Molecular Characterization of a Novel Mutated AHAS Gene Responsible for the Resistance of AHAS-Inhibiting Herbicides in Rapeseed (Brassica napus L.).

The use of herbicides is an effective and economic way to control weeds, but their availability for rapeseed is limited due to the shortage of herbicide-resistant cultivars in China. The single-point mutation in the acetohydroxyacid synthase (AHAS) gene can lead to AHAS-inhibiting herbicide resistance. In this study, the inheritance and molecular characterization of the tribenuron-methyl (TBM)-resistant rapeseed (Brassica napus L.) mutant, K5, are performed. Results indicated that TBM-resistance of K5 was controlled by one dominant allele at a single nuclear gene locus. The novel substitution of cytosine with thymine at position 544 in BnAHAS1 was identified in K5, leading to the alteration of proline with serine at position 182 in BnAHAS1. The TBM-resistance of K5 was approximately 100 times that of its wild-type ZS9, and K5 also showed cross-resistance to bensufuron-methyl and monosulfuron-ester sodium. The BnAHAS1544T transgenic Arabidopsis exhibited higher TBM-resistance than that of its wild-type, which confirmed that BnAHAS1544T was responsible for the herbicide resistance of K5. Simultaneously, an allele-specific marker was developed to quickly distinguish the heterozygous and homozygous mutated alleles BnAHAS1544T. In addition, a method for the fast screening of TBM-resistant plants at the cotyledon stage was developed. Our research identified and molecularly characterized one novel mutative AHAS allele in B. napus and laid a foundation for developing herbicide-resistant rapeseed cultivars.

[An improved method for in vivo electroporation of morpholinos into the adult zebrafish retina].

In vivo electroporation of morpholinos (MOs) into the retina of adult zebrafish is an efficient method to study gene function related to retinal disease and regeneration. However, the currently reported methods are complicated with low MO transfer efficiency and high probability to cause collateral damage. The present study was aimed to optimize the existing MO electroporation methods. Two major changes were made to MO electroporation procedure in zebrafish retina. One was to coat the inner side of the electrode with ultrasonic gel. The other was to replace the commonly used round electrode with novel rectangular one. The results showed that the use of ultrasonic gel reduced collateral damage caused by retinal electroporation and simplified the experimental procedure. The rectangular electrode significantly increased transfection efficiency of MO electroporation. In particular, knocking down the expression of Ascl1a in the retina by using our method significantly inhibited the generation of retinal progenitor cells. These results suggest our method is the optimization of the current MO electroporation methods and may be a better alternative for relevant researchers.

Identification and characterization of microRNAs in the flag leaf and developing seed of wheat (Triticum aestivum L.).

BACKGROUND: MicroRNAs (miRNAs) regulate various biological processes in plants. Considerable data are available on miRNAs involved in the development of rice, maize and barley. In contrast, little is known about miRNAs and their functions in the development of wheat. In this study, five small RNA (sRNA) libraries from wheat seedlings, flag leaves, and developing seeds were developed and sequenced to identify miRNAs and understand their functions in wheat development. RESULTS: Twenty-four known miRNAs belonging to 15 miRNA families were identified from 18 MIRNA loci in wheat in the present study, including 15 miRNAs (9 MIRNA loci) first identified in wheat, 13 miRNA families (16 MIRNA loci) being highly conserved and 2 (2 MIRNA loci) moderately conserved. In addition, fifty-five novel miRNAs were also identified. The potential target genes for 15 known miRNAs and 37 novel miRNAs were predicted using strict criteria, and these target genes are involved in a wide range of biological functions. Four of the 15 known miRNA families and 22 of the 55 novel miRNAs were preferentially expressed in the developing seeds with logarithm (log2) of the fold change of 1.0 ~ 7.6, and half of them were seed-specific, suggesting that they participate in regulating wheat seed development and metabolism. From 5 days post-anthesis to 20 days post-anthesis, miR164 and miR160 increased in abundance in the developing seeds, whereas miR169 decreased, suggesting their coordinating functions in the different developmental stages of wheat seed. Moreover, 8 known miRNA families and 28 novel miRNAs exhibited tissue-biased expression in wheat flag leaves, with the logarithm of the fold changes of 0.1 ~ 5.2. The putative targets of these tissue-preferential miRNAs were involved in various metabolism and biological processes, suggesting complexity of the regulatory networks in different tissues. Our data also suggested that wheat flag leaves have more complicated regulatory networks of miRNAs than developing seeds. CONCLUSIONS: Our work identified and characterised wheat miRNAs, their targets and expression patterns. This study is the first to elucidate the regulatory networks of miRNAs involved in wheat flag leaves and developing seeds, and provided a foundation for future studies on specific functions of these miRNAs.

NIR light-propelled bullet-shaped carbon hollow nanomotors with controllable shell thickness for the enhanced dye removal.

Materials with asymmetric nanostructures have attracted tremendous research attention due to their unique structural characteristics, excellent physicochemical properties, and promising prospects. However, it is still difficult to design and fabricate bullet-shaped nanostructure due to its structural complexity. Herein, for the first time, we successfully constructed NIR light-propelled bullet-shaped hollow carbon nanomotors (BHCNs) with an open mouth on the bottom of nano-bullet for the enhanced dye removal, by employing bullet-shaped silica nanoparticles (B-SiO2 NPs) as a hard template. BHCNs were formed by the growth of polydopamine (PDA) layer on the heterogeneous surface of B-SiO2 NPs, followed by the carbonization of PDA and subsequent selective etching of SiO2. The shell thickness of BHCNs was able to be facilely controlled from ≈ 14 to 30 nm by tuning the added amount of dopamine. The combination of streamlined bullet-shaped nanostructure with good photothermal conversion efficiency of carbon materials facilitated the generation of asymmetric thermal gradient field around itself, thus driving the motion of BHCNs by self-thermophoresis. Noteworthily, the diffusion coefficient (De) and velocity of BCHNs with shell thickness of 15 nm (BHCNs-15) reached to 43.8 µm⋅cm-2 and 11.4 µm⋅s-1, respectively, under the illumination of 808 nm NIR laser with the power density of 1.5 W⋅cm-2. The NIR laser propulsion caused BCHNs-15 to enhance the removal efficiency (53.4% vs. 25.4%) of methylene blue (MB) as a typical dye because the faster velocity could produce the higher micromixing role between carbon adsorbent and MB. Such a smart design of the streamlined nanomotors may provide a promising potential in environmental treatment, biomedical and biosensing applications.

Effect of statins on the treatment of early diabetic nephropathy: a systematic review and meta-analysis of nine randomized controlled trials.

BACKGROUND: Diabetic nephropathy (DN) is a secondary disease of diabetes and could cause serious renal damage. This article aimed to investigate the effect of statins on the treatment of early DN. METHODS: The databases were searched: Embase (January 2000-August 2021), PubMed (January 2000-August 2021), Cochrane [randomized controlled trial (RCT) database], Ovid (January 2000-August 2021), and clinicaltrials.gov (January 2000-August 2021) to obtain RCT literature related to statin intervention and DN. After screening, the risk of bias assessment was performed using the RevMan 5.4 software bias assessment tool, which was then used to perform the meta-analysis and obtain the therapeutic effects of statins by estimating indicators such as estimated glomerular filtration rate (eGFR), serum creatinine (SCR), total cholesterol (TC) level, total triglyceride (TG), and high-sensitivity C-reactive protein (hs-CRP). RESULTS: A total of 9 articles, 3,426 patients, and 5 types of statins were included. Meta-analysis showed that after treatment, eGFR in the experimental group was higher than in the control group [mean difference (MD) =5.80; 95% confidence interval (CI): (2.21, 9.40); P=0.002], SCR was lower than in the control group [MD =-0.46; 95% CI: (-0.69, -0.24); P<0.0001], hs-CRP level was lower than in the control group [MD =-1.20; 95% CI: (-2.05, -0.36); P=0.005], TC level was lower than in the control group [MD =-54.09; 95% CI: (-68.02, -40.16); P<0.00001], and TG level was lower than that in the control group [MD =-42.19; 95% CI: (-55.54, -28.84); P<0.00001]. DISCUSSION: Statins can significantly increase eGFR, reduce SCR, decrease CRP level, and decrease blood lipid level in the treatment of DN, thus reducing the inflammatory response and protecting the kidney.

Male Sterility of an AHAS-Mutant Induced by Tribenuron-Methyl Solution Correlated With the Decrease of AHAS Activity in Brassica napus L.

Tribenuron-methyl (TBM), an acetohydroxyacid synthase (AHAS)-inhibiting herbicide, can be used as an efficient chemical hybridization agent to induce male sterility for practical utilization of heterosis in rapeseed (Brassica napus L.). Utilization of rapeseed mutants harboring herbicide-resistant AHAS alleles as the male parent can simplify the hybrid seed production protocol. Here we characterized a novel TBM-resistant mutant K5 derived from an elite rapeseed variety, Zhongshuang No. 9 (ZS9), by ethyl methyl sulfonate mutagenesis. Comparative analysis of three BnAHAS genes (BnAHAS1, BnAHAS2, and BnAHAS3) between the mutant K5 and ZS9 identified a C-to-T transition at 544 from the translation start site in BnAHAS1 in K5 (This resistant allele is referred to as BnAHAS1544T ), which resulted in a substitution of proline with serine at 182 in BnAHAS1. Both ZS9 and K5 plants could be induced complete male sterility under TBM treatment (with 0.10 and 20 mg⋅L-1 of TBM, respectively). The relationship between TBM-induced male sterility (Y) and the relative AHAS activity of inflorescences (X) could be described as a modified logistic function, Y = 100-A/(1+Be(-KX)) for the both genotypes, although the obtained constants A, B, and K were different in the functions of ZS9 and K5. Transgenic Arabidopsis plants expressing BnAHAS1544T exhibited a higher TBM resistance of male reproductive organ than wild type, which confirmed that the Pro-182-Ser substitution in BnAHAS1 was responsible for higher TBM-resistance of male reproductive organs. Taken together, our findings provide a novel valuable rapeseed mutant for hybrid breeding by chemical hybridization agents and support the hypothesis that AHAS should be the target of the AHAS-inhibiting herbicide TBM when it is used as chemical hybridization agent in rapeseed.

Global Dynamic Transcriptome Programming of Rapeseed (Brassica napus L.) Anther at Different Development Stages.

Rapeseed (Brassica napus L.) is an important oil crop worldwide and exhibits significant heterosis. Effective pollination control systems, which are closely linked to anther development, are a prerequisite for utilizing heterosis. The anther, which is the male organ in flowering plants, undergoes many metabolic processes during development. Although the gene expression patterns underlying pollen development are well studied in model plant Arabidopsis, the regulatory networks of genome-wide gene expression during rapeseed anther development is poorly understood, especially regarding metabolic regulations. In this study, we systematically analyzed metabolic processes occurring during anther development in rapeseed using ultrastructural observation and global transcriptome analysis. Anther ultrastructure exhibited that numerous cellular organelles abundant with metabolic materials, such as elaioplast, tapetosomes, plastids (containing starch deposits) etc. appeared, accompanied with anther structural alterations during anther development, suggesting many metabolic processes occurring. Global transcriptome analysis revealed dynamic changes in gene expression during anther development that corresponded to dynamic functional alterations between early and late anther developmental stages. The early stage anthers preferentially expressed genes involved in lipid metabolism that are related to pollen extine formation as well as elaioplast and tapetosome biosynthesis, whereas the late stage anthers expressed genes associated with carbohydrate metabolism to form pollen intine and to accumulate starch in mature pollen grains. Finally, a predictive gene regulatory module responsible for early pollen extine formation was generated. Taken together, this analysis provides a comprehensive understanding of dynamic gene expression programming of metabolic processes in the rapeseed anther, especially with respect to lipid and carbohydrate metabolism during pollen development.