Tea is the world＇s oldest and most popular caffeine-containing beverage with immense economic, medicinal, and cultural importance. Here, we present the first high-quality nucleotide sequence of the ...repeat-rich （80.9%）, 3.02-Gb genome of the cultivated tea tree Camellia sinensis. We show that an extraordinarily large genome size of tea tree is resulted from the slow, steady, and long-term amplification of a few LTR retrotransposon families. In addition to a recent whole-genome duplication event, lineage-specific expansions of genes associated with flavonoid metabolic biosynthesis were discovered, which enhance catechin production, terpene enzyme activation, and stress tolerance, important features for tea flavor and adaptation. We demonstrate an independent and rapid evolution of the tea caffeine synthesis pathway relative to cacao and coffee. A comparative study among 25 Camellia species revealed that higher expression levels of most flavonoid- and caffeinebut not theanine-related genes contribute to the increased production of catechins and caffeine and thus enhance tea-processing suitability and tea quality. These novel findings pave the way for further metabolomic and functional genomic refinement of characteristic biosynthesis pathways and will help develop a more diversified set of tea flavors that would eventually satisfy and attract more tea drinkers worldwide.
In this paper, by using the superabsorbent polymers (SAPs) from baby diaper, the 3D porous composites decorated with NiO and Ni nanoparticles (NNSCs) have been prepared via a facile dissolving‐freeze ...drying and subsequent annealing reactions. The porous carbon matrix (PCM) derived from the SAPs also provides a continuous highly conductive network to facilitate the fast charge transfer and form a stable solid electrolyte interface film. Furthermore, NNSC can exhibit the high specific capacity and excellent cycle performance as anode materials for lithium‐ion batteries. And more importantly, employing the PCM derived from baby diaper offers a green approach for other energy storage materials.
A porous network decorated with NiO nanoparticles is prepared by using the superabsorbent polymers from fresh baby diapers via a facile annealing reaction. The composite exhibits high specific capacity and excellent cycle performance as anode materials for lithium‐ion batteries.
Comparative genomic analyses among closely related species can greatly enhance our understanding of plant gene and genome evolution. We report de novo-assembled AA-genome sequences for Oryza nivara , ...Oryza glaberrima , Oryza barthii , Oryza glumaepatula , and Oryza meridionalis . Our analyses reveal massive levels of genomic structural variation, including segmental duplication and rapid gene family turnover, with particularly high instability in defense-related genes. We show, on a genomic scale, how lineage-specific expansion or contraction of gene families has led to their morphological and reproductive diversification, thus enlightening the evolutionary process of speciation and adaptation. Despite strong purifying selective pressures on most Oryza genes, we documented a large number of positively selected genes, especially those genes involved in flower development, reproduction, and resistance-related processes. These diversifying genes are expected to have played key roles in adaptations to their ecological niches in Asia, South America, Africa and Australia. Extensive variation in noncoding RNA gene numbers, function enrichment, and rates of sequence divergence might also help account for the different genetic adaptations of these rice species. Collectively, these resources provide new opportunities for evolutionary genomics, numerous insights into recent speciation, a valuable database of functional variation for crop improvement, and tools for efficient conservation of wild rice germplasm.
Significance Asian rice ( Oryza sativa ) is among the world’s most important crops. The genus Oryza has become a model for the study of plant genome structure, function, and evolution. We have undertaken de novo, full-genome sequence analysis of five diploid AA-genome species that are closely related to O. sativa . These species are native to quite different environments, representing four continents, thus exhibiting very different adaptations. Our studies identify specific genetic changes, in both gene copy number and the degree of diversifying natural selection, that indicate specific genes responsible for these adaptations, particularly in genes related to defense against pathogens and reproductive diversification. This genome discovery and comparative analysis provide a powerful tool for future Oryza study and rice improvement.
Dear Editor Panax notoginseng （Burk） F.H. Chen, belonging to the genus Panax （Araliaceae）, is one of the most highly valued medicinal plants in the world. The dried root of this plant, known as ...＂Sanchi＂, is one of the most commonly used traditional Chinese medicines and has been used as a top-class tonic for more than 2000 years.
The dynamics of long terminal repeat (LTR) retrotransposons and their contribution to genome evolution during plant speciation have remained largely unanswered. Here, we perform a genome-wide ...comparison of all eight
AA-genome species, and identify 3911 intact LTR retrotransposons classified into 790 families. The top 44 most abundant LTR retrotransposon families show patterns of rapid and distinct diversification since the species split over the last ∼4.8 MY (million years). Phylogenetic and read depth analyses of 11 representative retrotransposon families further provide a comprehensive evolutionary landscape of these changes. Compared with Ty1-
, independent bursts of Ty3-
retrotransposon expansions have occurred with the three largest showing signatures of lineage-specific evolution. The estimated insertion times of 2213 complete retrotransposons from the top 23 most abundant families reveal divergent life histories marked by speedy accumulation, decline, and extinction that differed radically between species. We hypothesize that this rapid evolution of LTR retrotransposons not only divergently shaped the architecture of rice genomes but also contributed to the process of speciation and diversification of rice.
Hepatocellular carcinoma (HCC) is known for its high mortality rate worldwide. Based on intensive studies, microRNA (miRNA) expression functions in tumor suppression. Therefore, we aimed to evaluate ...the contribution of miR-146a-5p to radiosensitivity in HCC through the activation of the DNA damage repair pathway by binding to replication protein A3 (RPA3). First, the limma package of R was performed to differentially analyze HCC expression chip, and regulative miRNA of RPA3 was predicted. Expression of miR-146a-5p, RPA3, and DNA damage repair pathway-related factors in tissues and cells was determined. The effects of radiotherapy on the expression of miR-146a-5p and RPA3 as well as on cell radiosensitivity, proliferation, cell cycle, and apoptosis were also assessed. The results showed that there exists a close correlation between miR-146a and the radiotherapy effect on HCC progression through regulation of RPA3 and the DNA repair pathway. The positive rate of ATM, pCHK2, and Rad51 in HCC tissues was higher when compared with that of the paracancerous tissues. SMMC-7721 and HepG2 cell proliferation were significantly inhibited following 8 Gy 6Mv dose. MiR-146a-5p restrained the expression of RPA3 and promoted the expression of relative genes associated with the DNA repair pathway. In addition, miR-146a-5p overexpression suppresses cell proliferation and enhances radiosensitivity and cell apoptosis in HCC cells. In conclusion, the present study revealed that miR-146a-5p could lead to the restriction of proliferation and the promotion of radiosensitivity and apoptosis in HCC cells through activation of DNA repair pathway and inhibition of RPA3.
To understand the potential genetic basis of highland adaptation of fungal pathogenicity, we present here the ~116 Mb de novo assembled high-quality genome of Ophiocordyceps sinensis endemic to the ...Qinghai-Tibetan Plateau. Compared with other plain-dwelling fungi, we find about 3.4-fold inflation of the O. sinensis genome due to a rapid amplification of long terminal repeat retrotransposons that occurred ~38 million years ago in concert with the uplift of the plateau. We also observe massive removal of thousands of genes related to the transport process and energy metabolism. O. sinensis displays considerable lineage-specific expansion of gene families functionally enriched in the adaptability of low-temperature of cold tolerance, fungal pathogenicity and specialized host infection. We detect signals of positive selection for genes involved in peroxidase and hypoxia to enable its highland adaptation. Resequencing and analyzing 31 whole genomes of O. sinensis, representing nearly all of its geographic range, exhibits latitude-based population divergence and nature selection for population inhabitation towards higher altitudes on the Qinghai-Tibetan Plateau.
The genus Camellia, belonging to the family Theaceae, is economically important group in flowering plants. Frequent interspecific hybridization together with polyploidization has made them become ...taxonomically "difficult taxa". The DNA content is often used to measure genome size variation and has largely advanced our understanding of plant evolution and genome variation. The goals of this study were to investigate patterns of interspecific and intraspecific variation of DNA contents and further explore genome size evolution in a phylogenetic context of the genus.
The DNA amount in the genus was determined by using propidium iodide flow cytometry analysis for a total of 139 individual plants representing almost all sections of the two subgenera, Camellia and Thea. An improved WPB buffer was proven to be suitable for the Camellia species, which was able to counteract the negative effects of secondary metabolite and generated high-quality results with low coefficient of variation values (CV) <5%. Our results showed trivial effects on different tissues of flowers, leaves and buds as well as cytosolic compounds on the estimation of DNA amount. The DNA content of C. sinensis var. assamica was estimated to be 1C = 3.01 pg by flow cytometric analysis, which is equal to a genome size of about 2940 Mb.
Intraspecific and interspecific variations were observed in the genus Camellia, and as expected, the latter was larger than the former. Our study suggests a directional trend of increasing genome size in the genus Camellia probably owing to the frequent polyploidization events.
There has been no systematic review evaluating the efficacy of electromyography (EMG) biofeedback after knee surgery recently. This meta-analysis aimed to determine whether EMG-biofeedback is ...effective for improving the range of motion (ROM), physical function, and pain relief in patients after knee. Randomized controlled trials (RCTs) assessing the effect of EMG-biofeedback after any knee surgery were retrieved from EMBASE, PubMed, Cochrane Library, Physiotherapy Evidence Database, ClinicalTrials.gov, ProQuest. This review identified 773 unique studies, and six RCTs were in the final meta-analysis. EMG-Biofeedback treatment has a significant difference compared to other rehabilitation therapy in knee ROM improving (SMD = −0.48, 95% CI = −0.82 to −0.14, p = 0.006, I2 = 37%). Moreover, there was no significant difference in pain (SMD = −0.33, 95% CI = −0.67 to0.02, p = 0.07, I2 = 41%) and physical function scores (MD = 1.83, 95% CI = −3.48 to7.14, p = 0.50, I2 = 0%). The results illustrate that EMG-biofeedback can improve knee ROM in patients after knee surgery. However, it is not superior to other rehabilitation methods for pain relief and physical function improvement.
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