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Ramie is one of the most ancient cellulose fiber crops, having been used for at least 6000 years. It is also one of the strongest and longest natural fine textile fibers in the world and is principally used for fabric production. Although ramie is very important and has a high economic value, the genetic basis of its yield-related and fiber quality traits remains poorly understood and is insufficient owing to the lack of assessment in multiple environments. Here, we evaluated the population structure and genomic variation in ramie based on resequencing of 319 core accessions and detected several candidate genes associated with fiber yield and quality traits by combining them with linkage mapping. We obtained approximately 3.49 million high-quality single nucleotide polymorphisms (SNPs), 2,089,798 insertions and deletions (Indels), and 88,087 structure variations (SVs). The investigation of phenotypes for plant height (PL), stem diameter (SD), bark thickness (BT), fiber diameter (FD), fiber fineness (FF), and ramet number (RN) found these traits showed abundant variation and correlation. Several genetic loci and candidate genes were identified associated with three yield-related traits and fiber fineness. A gene within pleiotropic loci encoding NAC domain containing protein (BnNAC29) was found to be significantly correlated with stem diameter and bark thickness. Another variation of large fragment insertions and deletions in two candidate genes, BnVIT1 and BnAEP, may also be responsible for the increase of stem diameter and bark thickness, respectively. Favorable gene haplotypes were identified as having the same tendency in stem diameter and bark thickness. Moreover, we presumed that plant height-related genes had undergone selection from landraces to breeding cultivars, even though there was minor differentiation during domestication. Our study provides new insights into the genetic architecture of yield and fiber quality traits in ramie. Moreover, the identification of fiber yield-related genetic loci and large-scale genomic variation represent valuable resources for genomics-assisted breeding of this fiber crop. [ABSTRACT FROM AUTHOR]

Purpose: Neuroblastoma is a challenging pediatric tumor with a need for improved treatment strategies. This study explores the role of disulfidptosis, a form of cell death induced by intracellular disulfide accumulation, in neuroblastoma and its implications for prognosis and immune infiltration. Methods: We subgrouped neuroblastoma samples based on disulfidptosis-related gene expression and constructed a disulfidptosis potential index (DPI) to quantify disulfidptosis levels in neurobalstoma. The correlation between DPI, outcome, immune infiltration, and drug sensitivity were explored. Results: Combing RNA-seq and single-cell dataset, we found that higher disulfidptosis potential index (DPI) is associated with poorer outcomes in neuroblastoma patients, indicating the detrimental impact of enhanced disulfide stress and cellular dysfunction. Furthermore, we found that higher DPI is correlated with reduced immune infiltration within the tumor microenvironment, highlighting an immunosuppressive milieu in high DPI neuroblastomas. The DPI-high neuroblastoma may benefit from the estrogen pathway related drug fulvestrant. Conclusion: Overall, this study highlights the significance of disulfidptosis as a potential therapeutic target and underscores the importance of integrating immune modulation strategies, offering new avenues for improved management of neuroblastoma. [ABSTRACT FROM AUTHOR]

Remediation of cadmium (Cd) pollution is one of the priorities of global environmental governance and accurate detection of Cd content is a key link in remediation of Cd pollution. This study aimed to compare three methods (inductively coupled plasma optical emission spectrometry (ICP-OES), inductively coupled plasma mass spectrometry (ICP-MS), and graphite furnace-atomic absorption spectrometry (GF-AAS)) for the determination of Cd with different tissues of various ramie varieties, and distinguish the advantage and disadvantage of each method. In total, 162 samples of ramie (Boehmeria nivea L.), which is an ideal plant for heavy metal remediation, were detected and the results showed that the three methods were all suitable for the de-termination of Cd content in ramie. ICP-OES and ICP-MS were simpler, faster, and more sensitive than GF-AAS. ICP-MS could be recommended for the determination of samples with various concentrations of Cd. ICP-OES could be used for measurement of samples with > 100 mg/kg Cd content, while GF-AAS was suitable for the detection of samples with very high (> 550 mg/kg) or very low (< 10 mg/kg) Cd content. Overall, considering the accuracy, stability, and the cost of measurement, ICP-MS was the most suitable method for determination of Cd content. This study provides significant reference information for the research in the field of Cd pollution remediation. [ABSTRACT FROM AUTHOR]

Abscisic acid (ABA) is known as an important hormone regulating plant stress resistance, such as salt, drought and heavy metal resistance. However, the relationship between ABA and cadmium (Cd) enrichment in ramie (Boehmeria nivea L.) is still unclear to date. This study aimed to reveal the effect of ABA on Cd enrichment in ramie, and we received the following results: (1) Under Cd treatment, the Cd uptake of ramie increased with the increase of Cd concentration, but the chlorophyll content decreased. Under Cd treatment, the ABA content was highest in roots of ramie, followed by that in old leaves, and lowest in new leaves. Long-time treatment of high Cd concentration reduced the ability of endogenous ABA biosynthesis. (2) Spraying ABA on ramie plants (SORP) and adding ABA directly to the culture solution (ADCS) with low concentration can promote the growth of ramie and increase the amount of Cd uptake, and the effect of SORP is better. (3) The molecular reason for the decrease of chlorophyll content due to Cd stress, may be resulted from the down-regulated expression of the chlorophyll synthesis genes (BnPAO and BnNYC1) and the up-regulated expression of the chlorophyll degradation genes (BnCHLH, BnCHLG, BnHAP3A and BnPPR1). The elevated ABA content in ramie plants may due to the up-regulated expression of the ABA synthesis related genes (BnABA1, BnNCED3, and BnNCED5) and the genes (BnABCG40, BnNFXL2, BnPYL9, BnGCR2, BnGTG1, BnBGLU1, BnUTG1, BnVHAG1 and BnABI5) that encoding ABA transport and response proteins, which was consistent with the enhance the Cd uptake in ramie. Our study revealed the relationship between ABA and Cd uptake in ramie, which provided a reference for improving the enrichment of Cd in ramie. [ABSTRACT FROM AUTHOR]

Flavonoids contained in ramie (Boehmeria nivea) root are important resources for officinal use. The plant seedling can grow optimally and develop an easy-harvesting adventitious root system in a hydroponic system. This research was carried out to unravel the regulation mechanism of flavonoid biosynthesis under hydroponic culturing condition, which hitherto remained unknown. Root samples of the ramie plants grown in soil and hydroponic conditions at different developmental stages were collected and pooled for transcriptome sequencing, and the expression levels of flavonoid biosynthesis-related genes and total flavonoid content were quantified. A total of 43,541 unigenes were finally annotated and the expression of 9 key unigenes were confirmed by qRT-PCR. The flavonoid biosynthesis-related gene BnF3H was significantly up-regulated in the roots of hydroponic ramie, and higher total flavonoids content in the hydroponic ramie roots was also observed. The large dataset of transcripts and unigenes provided abundant genetic information for identifying flavonoid biosynthesis genes in ramie roots. Our results suggest flavonoid biosynthesis in ramie roots is positively affected in aquatic environment, and hydroponic culturing could have a potential for enhancing total flavonoids content in ramie roots. [ABSTRACT FROM AUTHOR]

A new fluorometric method is delineated for the detection of RNase H activity by combining DNAzyme with reduced graphene oxide (rGO). In the absence of RNase H, the fluorescence of FAM-labeled probe is quenched due to the strong adsorption on the rGO. The presence of RNase H can release the active DNAzyme from the DNA-RNA chimeric strand. This triggers the cleavage of the signal probe at the rA site with the help of the cofactor Mg2+. The recycle cleavage can directly result in the amplified signal emitted by the FAM-labeled short fragment. The method allows the activity of RNase H to be detected in a linear range of 0.01 to 5 U·mL−1. The detection limit of 0.018 U·mL−1 is calculated by the principle of three-time standard deviation over the blank signal. Then, RNase H-targeting natural compounds were screened for their inhibitory action. Among the investigated compounds, five were screened as RNase H inhibitors in a concentration-dependent manner, and 4 compounds were identified as activators. Finally, the method was reliably used for discriminating the difference of RNase H activity in human serum. It is found that RNase H activity was upregulated in patients with hepatitis C virus infection. [ABSTRACT FROM AUTHOR]