1.Sequencing VP4, VP7, NSP1, NSP4 genes of human rotavirus strain G1P8
Huong Thu Ngo ; Luan Thi Le ; Hien Dang Nguyen
Journal of Preventive Medicine 2007;17(2):27-32
Background: Rotavirus is the main cause of acute viral gastroenteritis in children under 5 years old. The virus leads to over 600000 children deaths a year in the world, 80% of which occur in the developing countries. In Viet Nam, 50%-70% the children\u2019s hospitalizations for acute diarrhea were resulted from rotavirus infection. Objective: To sequence nucleotides and amino acids of VP4, VP7, NSP1, and NSP4 genes of 5 passages of human rotavirus strain G1P8. Materials and method: A study was conducted in rotavirus sample of 5 passages of human rotavirus strain G1P8: B17A3; B17.3; B17.3 pp32vero15; B17.3 pp36TKP2; B17.3 pp43.7vero in Centre for Disease Control and Prevention, Atlanta, United State. Methods: using NucliSen Kit for detection of ARN; RT-PCR; sequencing genes by ABI 3100 machine. Results and Conclusion: Sequencing nucleotides and amino acids of VP4, VP7, NSP1, and NSP4 genes of 5 passages of human rotavirus strain G1P8 showed that: the number of nucleotide mutations ofVP4, VP7, NSP4 genes occurring among the passages were 3 (at nucleotit 175, 419, 790), 1 (at nucleotit 644), 3 (at nucleotit 134, 254, 482), respectively. All these mutations resulted in changes in amino acid composition. No mutation was found in NSP1 gene.
Rotavirus
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Genes
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Nucleotides/ genetics
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2.Reappraisal of double-hit lymphoma.
Chinese Journal of Pathology 2014;43(8):505-507
Genes, myc
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Humans
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Lymphoma
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genetics
3.Recent advances of pancreatic cancer.
Wen-ze WANG ; Zhi-yong LIANG ; Tong-hua LIU
Chinese Journal of Pathology 2007;36(1):53-55
4.Pyramiding of 3-resistant-gene to improve rice blast resistance of a restorer line, Fuhui 673.
Zhiwei CHEN ; Huazhong GUAN ; Xiaofang WANG ; Ruixia DONG ; Chenghai ZHUO ; Damei MAO ; Runsen PAN ; Yuanchang ZHOU ; Weiren WU
Chinese Journal of Biotechnology 2019;35(5):837-846
To improve the blast resistance of elite rice restorer line Fuhui 673, 3 blast resistance genes Pi-1, Pi-9 and Pi-kh were introduced into Fuhui 673 from a good-quality restorer line Jinhui 1059 through 3 successive backcrosses followed by one selfing using the technique of marker-assisted selection. Ten near-isogenic lines (NILs) of Fuhui 673 carrying the 3 introduced resistance genes were created. Genotype analysis using 68 SSR markers evenly distributed in the genome indicated that 92.96%-98.59% of the NILs' genetic background had been recovered to Fuhui 673. Both indoor and field resistance tests indicated that the NILs and their hybrids with sterile line Yixiang A were all resistant to rice blast, with resistance levels significantly higher than those of controls Fuhui 673 and hybrid Yiyou 673 (Yixiang A Fuhui 673). In addition, among the 10 hybrids between the NILs and Yixiang A, 2 showed significantly higher yield than and 4 displayed similar yield to that of control Yiyou 673, suggesting that most of the NILs retained the elite characteristics of Fuhui 673. Two new hybrid rice cultivars Liangyou 7283 and Jintaiyou 683 from NIL Line 9 showed high yield, good resistance to blast and moderate growth period in regional trial, suggesting that the NIL Line 9 has a good prospect for application.
Breeding
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Disease Resistance
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genetics
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Genes, Plant
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genetics
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Oryza
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genetics
5.Differential transcription of mating-type genes during sexual reproduction of natural Cordyceps sinensis.
Xiu-Zhang LI ; Yu-Ling LI ; Jia-Shi ZHU
China Journal of Chinese Materia Medica 2023;48(10):2829-2840
Natural Cordyceps sinensis as an insect-fungal complex, which is developed after Ophiocordyceps sinensis infects a larva of Hepialidae family. Seventeen genotypes of O. sinensis have been identified in natural C. sinensis. This paper summarized the literature reports and GenBank database regarding occurrence and transcription of the mating-type genes of MAT1-1 and MAT1-2 idiomorphs in natural C. sinensis, in Hirsutella sinensis(GC-biased Genotype #1 of O. sinensis), to infer the mating pattern of O. sinensis in the lifecycle of natural C. sinensis. The mating-type genes and transcripts of MAT1-1 and MAT1-2 idiomorphs were identified in the metagenomes and metatranscriptomes of natural C. sinensis. However, their fungal sources are unclear because of co-colonization of several genotypes of O. sinensis and multiple fungal species in natural C. sinensis. The mating-type genes of MAT1-1 and MAT1-2 idiomorphs were differentially present in 237 H. sinensis strains, constituting the genetic control of the O. sinensis reproduction. Transcriptional control of the O. sinensis reproduction includes: differential transcription or silencing of the mating-type genes of MAT1-1 and MAT1-2 idiomorphs, and the MAT1-2-1 transcript with unspliced intron I that contains 3 stop codons. Research on the H. sinensis transcriptome demonstrated differential and complementary transcriptions of the mating-type genes of MAT1-1 and MAT1-2 idiomorphs in Strains L0106 and 1229, which may become mating partners to accomplish physiological heterothallism. The differential occurrence and transcription of the mating-type genes in H. sinensis are inconsistent with the self-fertilization hypothesis under homothallism or pseudohomothallism, but instead indicate the need of mating partners of the same H. sinensis species, either monoecious or dioecious, for physiological heterothallism, or heterospecific species for hybridization. Multiple GC-and AT-biased genotypes of O. sinensis were identified in the stroma, stromal fertile portion(densely covered with numerous ascocarps) and ascospores of natural C. sinensis. It needs to be further explored if the genome-independent O. sinensis genotypes could become mating partners to accomplish sexual reproduction. S. hepiali Strain FENG experienced differential transcription of the mating-type genes with a pattern complementary to that of H. sinensis Strain L0106. Additional evidence is needed to explore a hybridization possibility between S. hepiali and H. sinensis, whether they are able to break the interspecific reproductive isolation. Genotypes #13~14 of O. sinensis feature large DNA segment reciprocal substitutions and genetic material recombination between 2 heterospecific parental fungi, H. sinensis and an AB067719-type fungus, indicating a possibility of hybridization or parasexuality. Our analysis provides important information at the genetic and transcriptional levels regarding the mating-type gene expression and reproduction physiology of O. sinensis in the sexual life of natural C. sinensis and offers crucial reproductive physiology evidence, to assist in the design of the artificial cultivation of C. sinensis to supplement the increasing scarcity of natural resource.
Cordyceps/genetics*
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Genes, Mating Type, Fungal/genetics*
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Reproduction/genetics*
6.Recent advances in gene change of pancreatic cancer.
Acta Academiae Medicinae Sinicae 2004;26(1):79-82
A large number of data derived from molecular analyses support the hypothesis that human cancer is a genetic disease and a distinct subset of genes have been found to be genetically changed in most tumors. Molecular alterations in pancreatic cancer include: (1) oncogenes such as K-ras, c-myc, c-fos, and c-erbB-2; (2) tumor suppressor genes such as p53, p16, DPC4/SMAD4, and DCC; and (3) growth factors such as EGF, FGF, HGF, PDGF, VEGF, TGF-beta. Genetic alterations of K-ras and p53 are common in human pancreatic cancer, but the occurrence of pancreatic cancer is a multi-step phenomenon in which the accumulation of genetic changes is extremely important.
Epidermal Growth Factor
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genetics
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Fibroblast Growth Factors
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genetics
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Genes, Tumor Suppressor
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Genes, myc
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genetics
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Genes, p16
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Genes, p53
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genetics
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Genes, ras
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genetics
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Growth Substances
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genetics
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metabolism
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Humans
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Oncogenes
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genetics
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Pancreatic Neoplasms
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genetics
8.Preliminary study on gene related to acid tolerance of Streptococcus mutans.
Hua WEI ; Ming-wen FAN ; Zhuan BIAN ; Ping ZHANG ; Ying ZHOU
Chinese Journal of Stomatology 2004;39(5):382-385
OBJECTIVETo construct an acid-sensitive mutant of Streptococcus mutans (S. mutans) by transposon mutagenesis and to find a new gene related to the acid tolerance of S. mutans.
METHODSThe transposon Tn917 was delivered into S. mutans UA159 by the temperature-sensitive plasmid pTV1-OK bearing Tn917 and transposition of Tn917 was induced after incubation at non-permissive temperature (42 degrees C). Transposants harboring Tn917 in the chromosome were screened for the selection of mutant that had diminished growth at low pH. Southern analysis was performed with EcoRI (no cut within Tn917) digests of S. mutans UA159 and the selected aid-sensitive mutant, with DIG-labeled probe of 4.3 kb KpnI fragment of pTV1-OK containing Tn917. Genetic backcross experiment was performed by transforming the genome of the mutant to another S. mutans strain MT8148 to determine the linkage of Tn917 insertion to the change of phenotype (acid-sensitivity). Comparison of the abilities to grow at low pH, the glycolytic pH drop and killing pH values were done between the acid-sensitive mutant and the parent strain. The asymmetric PCR method was used to obtain the fragment flanking Tn917 and the PCR products were cloned to pMD18-T vector for sequencing.
RESULTSOne mutant that showed no growth at pH 5.0 was isolated from 2 316 transposants and was named as b23. Southern analysis and genetic backcross experiment confirmed the linkage between single Tn917 insertion into the chromosome and the phenotypic change (acid sensitive). b23 was less acid tolerant than UA159 in that it showed poorer growth at low pH and higher glycolytic pH minimum and higher killing pH. BLAST results indicated that Tn917 inserted into the genome of S. mutans UA159 at the site of 996 123 bp.
CONCLUSIONAn acid-sensitive mutant of S. mutans was successfully constructed and a new gene that is responsible for the acid tolerance in S. mutans UA159 was revealed.
Genes, Bacterial ; Streptococcus mutans ; genetics ; Sucrose ; metabolism
9.Research progress in biosynthesis of podophyllotoxin and its derivatives.
Zhen MENG ; Tingting YAO ; Wei ZHAO ; Hongmei LI ; Ya-Jie TANG
Chinese Journal of Biotechnology 2021;37(6):2026-2038
Podophyllotoxin (PTOX) is an aryl-tetralin lignan of plant origin found in some species of Podophyllum such as Dysosma versipellis, Diphylleia sinensis, and Sinopodophyllum hexandrum. Etoposide and teniposide are produced semisynthetically from PTOX and used clinically to treat several forms of cancer. As a typical representative of new drug discovery from natural products, the production of PTOX solely depends on extraction from plants, resulting in severe contradiction between supply and demand. With the advantages of unconstrained resources and eco-friendly reaction conditions, biosynthesis method has become a trend in the production of PTOX and its derivatives. In this review, we summarize the research progress of PTOX biosynthesis in plants and expound the functions of the key enzymes as well as their subcellular location. The synthetic biology for production of PTOX intermediates in a tobacco chassis is also introduced. Finally, the heterologous expression and biotransformation of PTOX in microorganisms is summarized, which sets the foundation for the efficient microbial production of PTOX using cell factories.
Genes, Plant
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Podophyllotoxin/biosynthesis*
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Podophyllum/genetics*