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122.
Xianhai Zhao Berit Ebert Baocai Zhang Huabin Liu Yutao Zhang Wei Zeng Carsten Rautengarten Huiling Li Xiaoyang Chen Antony Bacic Guodong Wang Shuzhen Men Yihua Zhou Joshua L. Heazlewood Ai‐Min Wu 《The Plant journal : for cell and molecular biology》2020,104(1):252-267
Rhamnogalacturonan‐II (RG‐II) is structurally the most complex glycan in higher plants, containing 13 different sugars and 21 distinct glycosidic linkages. Two monomeric RG‐II molecules can form an RG‐II‐borate diester dimer through the two apiosyl (Api) residues of side chain A to regulate cross‐linking of pectin in the cell wall. But the relationship of Api biosynthesis and RG‐II dimer is still unclear. In this study we investigated the two homologous UDP‐D‐apiose/UDP‐D‐xylose synthases (AXSs) in Arabidopsis thaliana that synthesize UDP‐D‐apiose (UDP‐Api). Both AXSs are ubiquitously expressed, while AXS2 has higher overall expression than AXS1 in the tissues analyzed. The homozygous axs double mutant is lethal, while heterozygous axs1/+ axs2 and axs1 axs2/+ mutants display intermediate phenotypes. The axs1/+ axs2 mutant plants are unable to set seed and die. By contrast, the axs1 axs2/+ mutant plants exhibit loss of shoot and root apical dominance. UDP‐Api content in axs1 axs2/+ mutants is decreased by 83%. The cell wall of axs1 axs2/+ mutant plants is thicker and contains less RG‐II‐borate complex than wild‐type Col‐0 plants. Taken together, these results provide direct evidence of the importance of AXSs for UDP‐Api and RG‐II‐borate complex formation in plant growth and development. 相似文献
123.
繁殖是植物种群更新与维持的重要环节。包括极小种群野生植物在内的受威胁物种, 其濒危原因是在长期演化过程中自身繁育力的衰退、生活力的下降等内在因素和人类的过度采挖和生境的破坏等外在因素共同作用的结果。对极小种群野生植物进行高效的人工繁殖, 能扩大种群数量并应用于迁地保护、自然回归和满足商品市场的需求, 有利于其种质资源的保护和可持续利用。为了保持物种的遗传多样性, 采用种子繁殖育苗是有效的方法, 扦插、嫁接和组织培养技术等无性繁殖方法则可用于对难以用种子繁殖的种类进行快速繁殖。本文对14种中国典型极小种群野生植物的繁殖特性和已有的人工繁殖方法进行了综述, 并简要介绍在其种苗繁殖研究方面取得的进展。其中利用播种繁殖成功的物种有12种, 共繁殖230,000株种苗; 利用扦插繁殖成功的物种有5种, 共繁殖33,100株种苗; 华盖木(Manglietiastrum sinicum)、河北梨(Pyrus hopeiensis)和黄梅秤锤树(Sinojackia huangmeiensis)采用嫁接繁殖出了2,415株种苗; 9个物种的组织培养技术获得成功, 共繁殖了24,850株种苗。这些种苗有些已应用于迁地保护和自然回归。上述研究结果为这14种极小种群野生植物的保护和利用提供了理论和技术基础, 也能为其他极小种群野生植物的保护和利用提供参考。 相似文献
124.
Tan Tingting Liu Rongpeng Luo Qin Ma Jingwen Ou Yao Zeng Wenhui Feng Lichun Xu Hanfu 《Transgenic research》2020,29(2):243-251
Transgenic Research - The cytoplasmic actin gene Actin4 (A4) in silkworm (Bombyx mori) was isolated 20 years ago and has a distal promoter upstream of the first exon and a proximal... 相似文献
125.
Tian Xin-Yue He Dong-Dong Bai Shuang Zeng Wen-Zhi Wang Zheng Wang Mo Wu Liang-Quan Chen Zhi-Chang 《Plant and Soil》2021,460(1-2):1-30
Plant and Soil - Phytoremediation of soil contaminated by trace elements is a technology using plants and microorganisms to sequester, inactivate, or extract contaminants from the soil. The... 相似文献
126.
Zeng Qingqing Wang Peiqi Ren Yongyu Kang Xiangyang 《Plant Cell, Tissue and Organ Culture》2021,147(2):255-270
Plant Cell, Tissue and Organ Culture (PCTOC) - The important role of polyploidy in plant evolution is widely recognized. However, many questions concerning how polyploidy affects the plant... 相似文献
127.
Plant litter quality regulates soil eco-enzymatic stoichiometry and microbial nutrient limitation in a citrus orchard 总被引:1,自引:0,他引:1
Plant and Soil - The impacts associated with litter decomposition in intensive cropping on eco-enzymatic stoichiometry and microbial nutrient limitation are still under debate. To evaluate the... 相似文献
128.
129.
Min Peng Weilin Zhu Chunling Yang Jiuxiang Yao Huifang Chen Weiming Jiang Zhenhan He Qiangyong Li Qingyun Liu Yongzhen Zhao Yong Lin Xiaohan Chen Digang Zeng Xiuli Chen 《Zeitschrift fur angewandte Ichthyologie》2021,37(1):73-82
The genetic diversity of 289 spotted scat (Scatophagus argus) from seven populations along the northern coast of the South China Sea was studied by analyzing the full-length sequences of the mitochondrial control region (D-LOOP). The S. argus D-LOOP sequence was 1,004–1,010 bp long and contained 156 variant sites. The seven studied S. argus populations had a high degree of genetic diversity (haplotype diversity [Hd] = 0.99135; nucleotide diversity (π) = 0.01313). There was no obvious genetic differentiation among the seven geographical populations and gene exchange was frequent (Fst = −0.01867–0.01117, p > .05). Four distinct mitochondrial lineages were identified in the phylogenetic tree and the haplotype network. The between-lineage Fst was 0.71690–0.84940 (p < .001), but these lineages showed no obvious phylogeographic pattern. Based on D-LOOP mutation rates, we estimated that the four lineages diverged approximately 513,800–93,600 years ago, during the Eocene ice age, at which time falling sea levels may have led to population segregation. We estimated that S. argus population expansion occurred approximately 2.29–0.68 million years ago, during the late Pleistocene. During this period, sea levels rose again, allowing previously separated lineages to come into sympatry, which eventually gave rise to a highly genetically diverse population without pyhlogeographic structure. Here, we characterized the genetic structure and differentiation of seven S. argus populations from the northern coast of the South China Sea. Our results suggested that the seven S. argus populations from the northern coast of the South China Sea have a relatively low level of genetic variation and can be considered a single unit for the purposes of fishery development, utilization, and management. 相似文献
130.
Zhang Huan Lu Ping Tang Hui-Ling Yan Hua-Juan Jiang Wei Shi Hang Chen Si-Yu Gao Mei-Mei Zeng Xiang-Da Long Yue-Sheng 《Cellular and molecular neurobiology》2021,41(6):1257-1269
Cellular and Molecular Neurobiology - Valproate (VPA), a widely-used antiepileptic drug, is a selective inhibitor of histone deacetylase (HDAC) that play important roles in epigenetic regulation.... 相似文献