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991.
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993.
Wei Liu Li Liang Lifeng Zhao Huan Tan Jie Wu Qihui Qin Xiaojun Gou Xiaohua Sun 《Bioorganic & medicinal chemistry letters》2019,29(3):487-490
To explore the application of photoremovable protecting groups (PPGs) in the field of combination chemotherapy, we designed and synthesized a photoresponsive hybrid prodrug 4 that bearing both doxorubicin (DOX) and combretastatin A4 (CA4). Light triggered drug release investigation found that DOX release was mainly accomplished by 405?nm light while CA4 release was mainly triggered by 365?nm light, i.e., prodrug 4 exhibited a quasi-sequential release behavior when a sequential light irradiation strategy was applied. Cell viability evaluation confirmed the increased cytotoxicity of prodrug 4 compared with individual drugs towards MDA-MB-231cells, indicating that a synergistic effect was achieved. 相似文献
994.
Liu Rongpeng Zeng Wenhui Tan Tingting Chen Tao Luo Qin Qu Dawei Tang Yiyun Long Dingpei Xu Hanfu 《Transgenic research》2019,28(5-6):627-636
Transgenic Research - The silkworm Bombyx mori is a valuable insect that synthesizes bulk amounts of fibroin protein in its posterior silk gland (PSG) and weaves these proteins into silk cocoons.... 相似文献
995.
Yangmei Li Xiaoxiao Liu Kaihao Tang Pengxia Wang Zhenshun Zeng Yunxue Guo Xiaoxue Wang 《Molecular microbiology》2019,111(2):495-513
Pf filamentous prophages are prevalent among clinical and environmental Pseudomonas aeruginosa isolates. Pf4 and Pf5 prophages are integrated into the host genomes of PAO1 and PA14, respectively, and play an important role in biofilm development. However, the genetic factors that directly control the lysis‐lysogeny switch in Pf prophages remain unclear. Here, we identified and characterized the excisionase genes in Pf4 and Pf5 (named xisF4 and xisF5, respectively). XisF4 and XisF5 represent two major subfamilies of functional excisionases and are commonly found in Pf prophages. While both of them can significantly promote prophage excision, only XisF5 is essential for Pf5 excision. XisF4 activates Pf4 phage replication by upregulating the phage initiator gene (PA0727). In addition, xisF4 and the neighboring phage repressor c gene pf4r are transcribed divergently and their 5′‐untranslated regions overlap. XisF4 and Pf4r not only auto‐activate their own expression but also repress each other. Furthermore, two H‐NS family proteins, MvaT and MvaU, coordinately repress Pf4 production by directly repressing xisF4. Collectively, we reveal that Pf prophage excisionases cooperate in controlling lysogeny and phage production. 相似文献
996.
997.
Hui Li Adam Thrash Juliet D. Tang Linlin He Jianbing Yan Marilyn L. Warburton 《The Plant journal : for cell and molecular biology》2019,98(5):853-863
Maize (Zea mays mays) oil is a rich source of polyunsaturated fatty acids (FAs) and energy, making it a valuable resource for human food, animal feed, and bio‐energy. Although this trait has been studied via conventional genome‐wide association study (GWAS), the single nucleotide polymorphism (SNP)‐trait associations generated by GWAS may miss the underlying associations when traits are based on many genes, each with small effects that can be overshadowed by genetic background and environmental variation. Detecting these SNPs statistically is also limited by the levels set for false discovery rate. A complementary pathways analysis that emphasizes the cumulative aspects of SNP‐trait associations, rather than just the significance of single SNPs, was performed to understand the balance of lipid metabolism, conversion, and catabolism in this study. This pathway analysis indicated that acyl‐lipid pathways, including biosynthesis of wax esters, sphingolipids, phospholipids and flavonoids, along with FA and triacylglycerol (TAG) biosynthesis, were important for increasing oil and FA content. The allelic variation found among the genes involved in many degradation pathways, and many biosynthesis pathways leading from FAs and carbon partitioning pathways, was critical for determining final FA content, changing FA ratios and, ultimately, to final oil content. The pathways and pathway networks identified in this study, and especially the acyl‐lipid associated pathways identified beyond what had been found with GWAS alone, provide a real opportunity to precisely and efficiently manipulate high‐oil maize genetic improvement. 相似文献
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Roger T. Chetelat Xiaoqiong Qin Meilian Tan Diana Burkart‐Waco Yosuke Moritama Xiuwen Huo Tim Wills Ricardo Pertuz 《The Plant journal : for cell and molecular biology》2019,100(4):836-850
The wild tomato relative Solanum sitiens is a xerophyte endemic to the Atacama Desert of Chile and a potential source of genes for tolerance to drought, salinity and low‐temperature stresses. However, until recently, strong breeding barriers prevented its hybridization and introgression with cultivated tomato, Solanum lycopersicum L. We overcame these barriers using embryo rescue, bridging lines and allopolyploid hybrids, and synthesized a library of introgression lines (ILs) that captures the genome of S. sitiens in the background of cultivated tomato. The IL library consists of 56 overlapping introgressions that together represent about 93% of the S. sitiens genome: 65% in homozygous and 28% in heterozygous (segregating) ILs. The breakpoints of each segment and the gaps in genome coverage were mapped by single nucleotide polymorphism (SNP) genotyping using the SolCAP SNP array. Marker‐assisted selection was used to backcross selected introgressions into tomato, to recover a uniform genetic background, to isolate recombinant sub‐lines with shorter introgressions and to select homozygous genotypes. Each IL contains a single S. sitiens chromosome segment, defined by markers, in the genetic background of cv. NC 84173, a fresh market inbred line. Large differences were observed between the lines for both qualitative and quantitative morphological traits, suggesting that the ILs contain highly divergent allelic variation. Several loci contributing to unilateral incompatibility or hybrid necrosis were mapped with the lines. This IL population will facilitate studies of the S. sitiens genome and expands the range of genetic variation available for tomato breeding and research. 相似文献
1000.
Chunlei Zhang Zhiguo Xiao Tongtong Qin Zhengpeng Yang 《Journal of molecular recognition : JMR》2019,32(6)
Combining the surface modification and molecular imprinting technique, a novel piezoelectric sensing platform with excellent molecular recognition capability was established for the detection of uric acid (UA) based on the immobilization of TiO2 nanoparticles onto quartz crystal microbalance (QCM) electrode and modification of molecularly imprinted TiO2 (MIT) layer on TiO2 nanoparticles. The performance of the fabricated biosensor was evaluated, and the results indicated that the biosensor exhibited high sensitivity in UA detection, with a linear range from 0.04 to 45 μM and a limit of detection of 0.01 μM. Moreover, the biosensor presented high selectivity towards UA in comparison with other interferents. The analytical application of the UA biosensor confirmed the feasibility of UA detection in urine sample. 相似文献