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901.
Regulation of fibroblast growth factor 8 (FGF8) in chicken embryonic stem cells differentiation into spermatogonial stem cells 下载免费PDF全文
902.
903.
Genetic structure and phylogenetic relationships of Ralstonia solanacearum strains from diverse origins in Guangdong Province,China 下载免费PDF全文
Bacterial wilt, caused by Ralstonia solanacearum species complex is a key yield‐limiting factor on crops in Guangdong province, China. The genetic diversity of 110 R. solanacearum strains collected from 16 host plants in different areas of Guangdong province was analysed using biovar and phylotype classification schemes. Of 110 strains, fifty‐five strains belong to biovar 3, fifty‐two strains belong to biovar 4, two strains belong to biovar 2 and one strain belonged to biovar 1. Phylotype‐specific multiplex PCR showed that 108 strains belonged to phylotype I (biovars 1, 3, 4) and two strains belonged to phylotype II (biovar 2). The result of phylogenetic relationships analysis based on egl gene sequences demonstrated that 108 strains of phylotype I were grouped into nine previously described sequevars and a new sequevar 57, and two strains of phylotype II were grouped into sequevar 1. Sequevars 15, 34 and 44 widely distributed in Guangdong were predominant sequevars. Sequevar 45 was first reported on potato and pumpkin in China. These results revealed the genetic structure and phylogenetic relationships of R. solanacearum population in Guangdong and will be helpful in bacterial wilt‐resistance breeding. 相似文献
904.
Rice copine genes OsBON1 and OsBON3 function as suppressors of broad‐spectrum disease resistance 下载免费PDF全文
Xin Yin Baohong Zou Xuexue Hong Mingjun Gao Weibing Yang Xiangbin Zhong Yang He Peng Kuai Yonggen Lou Jirong Huang Jian Hua Zuhua He 《Plant biotechnology journal》2018,16(8):1476-1487
Breeding for disease resistance is the most effective strategy to control diseases, particularly with broad‐spectrum disease resistance in many crops. However, knowledge on genes and mechanism of broad‐spectrum resistance and trade‐off between defence and growth in crops is limited. Here, we show that the rice copine genes OsBON1 and OsBON3 are critical suppressors of immunity. Both OsBON1 and OsBON3 changed their protein subcellular localization upon pathogen challenge. Knockdown of OsBON1 and dominant negative mutant of OsBON3 each enhanced resistance to rice bacterial and fungal pathogens with either hemibiotrophic or necrotrophic lifestyles. The defence activation in OsBON1 knockdown mutants was associated with reduced growth, both of which were largely suppressed under high temperature. In contrast, overexpression of OsBON1 or OsBON3 decreased disease resistance and promoted plant growth. However, neither OsBON1 nor OsBON3 could rescue the dwarf phenotype of the Arabidopsis BON1 knockout mutant, suggesting a divergence of the rice and Arabidopsis copine genes. Our study therefore shows that the rice copine genes play a negative role in regulating disease resistance and their expression level and protein location likely have a large impact on the balance between immunity and agronomic traits. 相似文献
905.
PeCHYR1, a ubiquitin E3 ligase from Populus euphratica,enhances drought tolerance via ABA‐induced stomatal closure by ROS production in Populus 下载免费PDF全文
Fang He Hou‐Ling Wang Hui‐Guang Li Yanyan Su Shuang Li Yanli Yang Cong‐Hua Feng Weilun Yin Xinli Xia 《Plant biotechnology journal》2018,16(8):1514-1528
Drought, a primary abiotic stress, seriously affects plant growth and productivity. Stomata play a vital role in regulating gas exchange and drought adaptation. However, limited knowledge exists of the molecular mechanisms underlying stomatal movement in trees. Here, PeCHYR1, a ubiquitin E3 ligase, was isolated from Populus euphratica, a model of stress adaptation in forest trees. PeCHYR1 was preferentially expressed in young leaves and was significantly induced by ABA (abscisic acid) and dehydration treatments. To study the potential biological functions of PeCHYR1, transgenic poplar 84K (Populus alba × Populus glandulosa) plants overexpressing PeCHYR1 were generated. PeCHYR1 overexpression significantly enhanced H2O2 production and reduced stomatal aperture. Transgenic lines exhibited increased sensitivity to exogenous ABA and greater drought tolerance than that of WT (wild‐type) controls. Moreover, up‐regulation of PeCHYR1 promoted stomatal closure and decreased transpiration, resulting in strongly elevated WUE (water use efficiency). When exposed to drought stress, transgenic poplar maintained higher photosynthetic activity and biomass accumulation. Taken together, these results suggest that PeCHYR1 plays a crucial role in enhancing drought tolerance via ABA‐induced stomatal closure caused by hydrogen peroxide (H2O2) production in transgenic poplar plants. 相似文献
906.
Germanium Thin Film Protected Lithium Aluminum Germanium Phosphate for Solid‐State Li Batteries 下载免费PDF全文
Yijie Liu Chao Li Bojie Li Hucheng Song Zhu Cheng Minrui Chen Ping He Haoshen Zhou 《Liver Transplantation》2018,8(16)
Solid‐state Li batteries using Na+ superionic conductor type solid electrolyte attracts wide interest because of its safety and high theoretical energy density. The NASCION type solid electrolyte LAGP (Li1.5Al0.5Ge0.5P3O12) shows favorable conductivity as well as good mechanical strength to prevent Li dendrite penetration. However, the instability of LAGP with Li metal remains a great challenge. In this work, an amorphous Ge thin film is sputtered on an LAGP surface, which can not only suppress the reduction reaction of Ge4+ and Li, but also produces intimate contact between the Li metal and the LAGP solid electrolyte. The symmetric cell with the Ge‐coated LAGP solid electrolyte shows superior stability and cycle performance for 100 cycles at 0.1 mA cm?2. A quasi‐solid‐state Li–air battery has also been assembled to further demonstrate this advantage. A stable cycling performance of 30 cycles in ambient air can be obtained. This work helps to achieve a stable and ionic conducting interface in solid‐state Li batteries. 相似文献
907.
908.
909.
Yuanjiang Cui Youlin Peng Qiang Zhang Saisai Xia Banpu Ruan Qiankun Xu Xiaoqi Yu Tingting Zhou He Liu Dali Zeng Guangheng Zhang Zhenyu Gao Jiang Hu Li Zhu Lan Shen Longbiao Guo Qian Qian Deyong Ren 《The Plant journal : for cell and molecular biology》2021,105(4):942-956
Lesion-mimic mutants (LMMs) provide a valuable tool to reveal the molecular mechanisms determining programmed cell death (PCD) in plants. Despite intensive research, the mechanisms behind PCD and the formation of lesions in various LMMs still remain to be elucidated. Here, we identified a rice (Oryza sativa) LMM, early lesion leaf 1 (ell1), cloned the causal gene by map-based cloning, and verified this by complementation. ELL1 encodes a cytochrome P450 monooxygenase, and the ELL1 protein was located in the endoplasmic reticulum. The ell1 mutant exhibited decreased chlorophyll contents, serious chloroplast degradation, upregulated expression of chloroplast degradation-related genes, and attenuated photosynthetic protein activity, indicating that ELL1 is involved in chloroplast development. RNA sequencing analysis showed that genes related to oxygen binding were differentially expressed in ell1 and wild-type plants; histochemistry and paraffin sectioning results indicated that hydrogen peroxide (H2O2) and callose accumulated in the ell1 leaves, and the cell structure around the lesions was severely damaged, which indicated that reactive oxygen species (ROS) accumulated and cell death occurred in the mutant. TUNEL staining and comet experiments revealed that severe DNA degradation and abnormal PCD occurred in the ell1 mutants, which implied that excessive ROS accumulation may induce DNA damage and ROS-mediated cell death in the mutant. Additionally, lesion initiation in the ell1 mutant was light dependent and temperature sensitive. Our findings revealed that ELL1 affects chloroplast development or function, and that loss of ELL1 function induces ROS accumulation and lesion formation in rice. 相似文献
910.
Jianwen He Riliang Liu Weijiang Zheng Huiduo Guo Yunnan Yang Ruqian Zhao Wen Yao 《Microbial biotechnology》2021,14(5):2116-2129
As global warming intensifies, emerging evidence has demonstrated high ambient temperature during pregnancy negatively affects maternal physiology with compromised pregnant outcomes; however, little is known about the roles of gut microbiota and its underlying mechanisms in this process. Here, for the first time, we explored the potential mechanisms of gut microbiota involved in the disrupted glycolipid metabolism via hepatic mitochondrial function. Our results indicate heat stress (HS) reduces fat and protein contents and serum levels of insulin and triglyceride (TG), while increases that of non-esterified fatty acid (NEFA), β-hydroxybutyric acid (B-HBA), creatinine and blood urea nitrogen (BUN) (P < 0.05). Additionally, HS downregulates both mitochondrial genes (mtDNA) and nuclear encoding mitochondrial functional genes with increasing serum levels of malondialdehyde (MDA) and 8-hydroxydeoxyguanosine (8-OHdG) (P < 0.05). Regarding microbial response, HS boosts serum levels of lipopolysaccharide (LPS) (P < 0.05) and alters β-diversity (ANOSIM, P < 0.01), increasing the proportions of Escherichia–Shigella, Acinetobacter and Klebsiella (q < 0.05), while reducing that of Ruminiclostridium, Blautia, Lachnospiraceae_NK4A136_group, Clostridium VadinBB60 and Muribaculaceae (q < 0.05). PICRUSt analysis predicts that HS upregulates 11 KEGG pathways, mainly including bile secretion and bacterial invasion of epithelial cells. The collective results suggest that microbial dysbiosis due to late gestational HS has strong associations with damaged hepatic mitochondrial function and disrupted metabolic profiles. 相似文献