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991.
Xiaokang Sun Jie Lv Fei Wang Chenyang Zhang Liangxiang Zhu Guangye Zhang Tongle Xu Zhenghui Luo Haoran Lin Xiaoping Ouyang Chunming Yang Chuluo Yang Gang Li Hanlin Hu 《Liver Transplantation》2024,14(3):2302731
Achieving high-performance in all-small-molecule organic solar cells (ASM-OSCs) significantly relies on precise nanoscale phase separation through domain size manipulation in the active layer. Nonetheless, for ASM-OSC systems, forging a clear connection between the tuning of domain size and the intricacies of phase separation proves to be a formidable challenge. This study investigates the intricate interplay between domain size adjustment and the creation of optimal phase separation morphology, crucial for ASM-OSCs’ performance. It is demonstrated that exceptional phase separation in ASM-OSCs’ active layer is achieved by meticulously controlling the continuity and uniformity of domains via re-packing process. A series of halogen-substituted solvents (Fluorobenzene, Chlorobenzene, Bromobenzene, and Iodobenzene) is adopted to tune the re-packing kinetics, the ASM-OSCs treated with CB exhibited an impressive 16.2% power conversion efficiency (PCE). The PCE enhancement can be attributed to the gradual crystallization process, promoting a smoothly interconnected and uniformly distributed domain size. This, in turn, leads to a favorable phase separation morphology, enhanced charge transfer, extended carrier lifetime, and consequently, reduced recombination of free charges. The findings emphasize the pivotal role of re-packing kinetics in achieving optimal phase separation in ASM-OSCs, offering valuable insights for designing high-performance ASM-OSCs fabrication strategies. 相似文献
992.
993.
Taiyu Chen Saba Riaz Philip Davey Ziyu Zhao Yaqi Sun Gregory F Dykes Fei Zhou James Hartwell Tracy Lawson Peter J Nixon Yongjun Lin Lu-Ning Liu 《The Plant cell》2023,35(2):795
Ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco) performs most of the carbon fixation on Earth. However, plant Rubisco is an intrinsically inefficient enzyme given its low carboxylation rate, representing a major limitation to photosynthesis. Replacing endogenous plant Rubisco with a faster Rubisco is anticipated to enhance crop photosynthesis and productivity. However, the requirement of chaperones for Rubisco expression and assembly has obstructed the efficient production of functional foreign Rubisco in chloroplasts. Here, we report the engineering of a Form 1A Rubisco from the proteobacterium Halothiobacillus neapolitanus in Escherichia coli and tobacco (Nicotiana tabacum) chloroplasts without any cognate chaperones. The native tobacco gene encoding Rubisco large subunit was genetically replaced with H. neapolitanus Rubisco (HnRubisco) large and small subunit genes. We show that HnRubisco subunits can form functional L8S8 hexadecamers in tobacco chloroplasts at high efficiency, accounting for ∼40% of the wild-type tobacco Rubisco content. The chloroplast-expressed HnRubisco displayed a ∼2-fold greater carboxylation rate and supported a similar autotrophic growth rate of transgenic plants to that of wild-type in air supplemented with 1% CO2. This study represents a step toward the engineering of a fast and highly active Rubisco in chloroplasts to improve crop photosynthesis and growth.Introducing a proteobacterial Rubisco with a greater carboxylation rate and a higher content of active sites into tobacco chloroplasts supports photosynthesis and growth at high CO2 concentrations.IN A NUTSHELL Background: Rubisco is the key enzyme responsible for fixing CO2. However, due to its intrinsically low catalytic turnover rate, Rubisco represents the ultimate rate-limiting step in plant photosynthesis. Improving Rubisco carboxylation and assembly in plants has been a long-standing challenge in crop engineering to meet the pressing need for increased global food production. There is mounting interest in replacing endogenous plant Rubisco with active non-native Rubisco candidates from other organisms to enhance photosynthetic carbon fixation. Question: The folding and assembly of Rubisco in chloroplasts are intricate processes that usually require a series of ancillary factors. Seeking a new Rubisco variant that can be produced in chloroplasts with a high yield and high catalytic performance, without the requirement for cognate assembly factors and activases, could help improve carbon fixation in crop plants. Finding: In this work, we introduced a Rubisco from a proteobacterium into tobacco chloroplasts to replace native tobacco Rubisco. In the proteobacteria, Rubisco is naturally encapsulated at a high density within a CO2-fixing protein organelle, the carboxysome. The foreign Rubisco derived from bacteria formed efficiently and was functional in chloroplasts without the need for exogenous chaperones. Intriguingly, the chloroplast-expressed bacterial Rubisco supported the autotrophic growth of transgenic plants at a similar rate to wild-type plants at 1% CO2. Next Step: The successful production of functional bacterial Rubisco represents a step toward installing faster, highly active Rubisco, functional carboxysomes, and eventually active CO2 concentration mechanisms into chloroplasts to improve Rubisco carboxylation, with the intent of enhancing crop photosynthesis and crop yield on a global scale. 相似文献
994.
菌群在促进人类健康方面发挥着重要的作用,而人体菌群紊乱可导致或加剧多种疾病。由于肺部菌群和肺部病变在空间上重叠,二者可能存在更紧密的联系。有研究者以肺部菌群为切入点,探索肺部疾病和健康的关系。但目前关于肺部菌群的检测技术和送检样本类型等实验实施过程中涉及的方法学问题尚未达成共识,样本污染问题在收集和测序过程中出现的频率越来越高,降低了研究的科学性和说服力。因此,为使研究者了解肺部菌群研究的方法学进展,避免陷入实验设计和方法选择的误区,本文就该领域的主要研究技术和影响肺部菌群检测结果的因素作一综述。
相似文献995.
Yuhan Lin Penglin Xia Fangyu Cao Cheng Zhang Yajie Yang Haitao Jiang Haishan Lin Hu Liu Ruling Liu Xiaodong Liu Jianming Cai 《Journal of cellular and molecular medicine》2023,27(2):246
Radiation‐induced intestinal injury (RIII) is a common complication after radiation therapy in patients with pelvic, abdominal, or retroperitoneal tumours. Recently, in the model of DSS (Dextran Sulfate Sodium Salt) ‐induced intestinal inflammatory injury, it has been found in the study that transgenic mice expressing hVDR in IEC (Intestinal Epithelial Cell) manifest highly anti‐injury properties in colitis, suggesting that activated VDR in the epithelial cells of intestine may inhibit colitis by protecting the mucosal epithelial barrier. In this study, we investigated the effect of the expression and regulation of VDR on the protection of RIII, and the radiosensitivity in vitro experiments, and explored the initial mechanism of VDR in regulating radiosensitivity of IEC. As a result, we found that the expression of VDR in intestinal tissues and cells in mice can be induced by ionizing radiation. VDR agonists are able to prolong the average survival time of mice after radiation and reduce the radiation‐induced intestinal injury. For lack of vitamin D, the radiosensitivity of intestinal epithelial cells in mice increased, which can be reduced by VDR activation. Ensuing VDR activation, the radiation‐induced intestinal stem cells damage is decreased, and the regeneration and differentiation of intestinal stem cells is promoted as well. Finally, on the basis of sequencing analysis, we validated and found that VDR may target the HIF/PDK1 pathway to mitigate RIII. We concluded that agonism or upregulation of VDR expression attenuates radiation‐induced intestinal damage in mice and promotes the repair of epithelial damage in intestinal stem cells. 相似文献
996.
Andrew Dippel Austin Gallegos Vineela Aleti Arnita Barnes Xiaoru Chen Elizabeth Christian Jared Delmar Qun Du Reza Esfandiary Erika Farmer Andrew Garcia Qing Li Jia Lin Weiyi Liu LeeAnn Machiesky Neil Mody Arun Parupudi Meagan Prophet Keith Rickert Kim Rosenthal Song Ren Harini Shandilya Reena Varkey Kevin Wons Yuling Wu Yueh-Ming Loo Mark T. Esser Nicole L. Kallewaard Sarav Rajan Melissa Damschroder Weichen Xu Gilad Kaplan 《MABS-AUSTIN》2023,15(1)
997.
Fruit colour is essential to seed dispersal, speciation, and biological diversity in global ecosystems. The relationship between fruit-colour variation and species diversification has long been of interest in evolutionary biology, but remains poorly understood at the genus level. Here, we used Callicarpa, a typical representative of pantropical angiosperm, to analyse whether fruit colours are correlated with biogeographic distribution, dispersal events, and diversification rate. We estimated a time-calibrated phylogeny for Callicarpa and reconstructed ancestral fruit colour. Utilizing phylogenetic methods, we estimated the major dispersal events across the phylogenetic tree and the most likely fruit colours related to each dispersal event, and tested whether the dispersal frequencies and distances of the four fruit colours between major biogeographical areas were equal. We then tested whether fruit colours are correlated with latitude, elevation, and diversification rate. Biogeographical reconstructions showed that Callicarpa originated in the East Asia and Southeast Asia during the Eocene (∼35.53 Ma) and diverse species diverged mainly in the Miocene and lasted into the Pleistocene. Large-scale dispersal events were significantly associated with violet-fruited lineages. Furthermore, different fruit colours were markedly correlated with different latitudes and elevations (e.g., violet fruits were correlated with higher latitudes and elevations; red fruits and black fruits with lower latitudes; white fruits with higher elevations). Notably, violet fruits were statistically associated with highest diversification rates, driving fruit colour variation among different regions globally. Our results contribute to further understanding why fruit colour is so variable at the genus level of angiosperms in different areas around the world. 相似文献
998.
999.
Jun Ma Qiang Li Lei Zhang Sen Cai Yuanyuan Liu Juncheng Lin Rongfeng Huang Yongqiang Yu Mingzhang Wen Tongda Xu 《植物学报(英文版)》2022,64(12):2425-2437
Callus induction,which results in fate transition in plant cells,is considered as the first and key step for plant regeneration.This process can be stimulated in different tissues by a callus-inducing medium(CIM),which contains a high concentration of phytohormone auxin.Although a few key regulators for callus induction have been identified,the multiple aspects of the regulatory mechanism driven by high levels of auxin still need further investigation.Here,we find that high auxin induces callus ... 相似文献
1000.
Yi‐Zhe Zhang Juncheng Lin Zhizhong Ren Chun‐Xiang Chen Daisuke Miki Si‐Si Xie Jian Zhang Ya‐Nan Chang Jing Jiang Jun Yan Qingshun Q. Li Jian‐Kang Zhu Cheng‐Guo Duan 《植物学报(英文版)》2021,63(4):707-722
Heterochromatin is widespread in eukaryotic genomes and has diverse impacts depending on its genomic context. Previous studies have shown that a protein complex, the ASI1‐AIPP1‐EDM2 (AAE) complex, participates in polyadenylation regulation of several intronic heterochromatin‐containing genes. However, the genome‐wide functions of AAE are still unknown. Here, we show that the ASI1 and EDM2 mostly target the common genomic regions on a genome‐wide level and preferentially interacts with genetic heterochromatin. Polyadenylation (poly(A) sequencing reveals that AAE complex has a substantial influence on poly(A) site usage of heterochromatin‐containing genes, including not only intronic heterochromatin‐containing genes but also the genes showing overlap with heterochromatin. Intriguingly, AAE is also involved in the alternative splicing regulation of a number of heterochromatin‐overlapping genes, such as the disease resistance gene RPP4. We provided evidence that genic heterochromatin is indispensable for the recruitment of AAE in polyadenylation and splicing regulation. In addition to conferring RNA processing regulation at genic heterochromatin‐containing genes, AAE also targets some transposable elements (TEs) outside of genes (including TEs sandwiched by genes and island TEs) for epigenetic silencing. Our results reveal new functions of AAE in RNA processing and epigenetic silencing, and thus represent important advances in epigenetic regulation. 相似文献