• Title/Summary/Keyword: DNA structure

Search Result 1,000, Processing Time 0.029 seconds

Plant breeding in the 21st century: Molecular breeding and high throughput phenotyping

  • Sorrells, Mark E.
    • Proceedings of the Korean Society of Crop Science Conference
    • /
    • 2017.06a
    • /
    • pp.14-14
    • /
    • 2017
  • The discipline of plant breeding is experiencing a renaissance impacting crop improvement as a result of new technologies, however fundamental questions remain for predicting the phenotype and how the environment and genetics shape it. Inexpensive DNA sequencing, genotyping, new statistical methods, high throughput phenotyping and gene-editing are revolutionizing breeding methods and strategies for improving both quantitative and qualitative traits. Genomic selection (GS) models use genome-wide markers to predict performance for both phenotyped and non-phenotyped individuals. Aerial and ground imaging systems generate data on correlated traits such as canopy temperature and normalized difference vegetative index that can be combined with genotypes in multivariate models to further increase prediction accuracy and reduce the cost of advanced trials with limited replication in time and space. Design of a GS training population is crucial to the accuracy of prediction models and can be affected by many factors including population structure and composition. Prediction models can incorporate performance over multiple environments and assess GxE effects to identify a highly predictive subset of environments. We have developed a methodology for analyzing unbalanced datasets using genome-wide marker effects to group environments and identify outlier environments. Environmental covariates can be identified using a crop model and used in a GS model to predict GxE in unobserved environments and to predict performance in climate change scenarios. These new tools and knowledge challenge the plant breeder to ask the right questions and choose the tools that are appropriate for their crop and target traits. Contemporary plant breeding requires teams of people with expertise in genetics, phenotyping and statistics to improve efficiency and increase prediction accuracy in terms of genotypes, experimental design and environment sampling.

  • PDF

Preparation of Trifluoroacetyl Chitosan Derivatives with Antiviral Activity (항바이러스 활성을 갖는 Trifluoroacetyl Chitosan 유도체의 제조)

  • Kim, Chun-Ho;Shin, Cha-Gyun;Shin, Kye-Sook;Son, Tae-il
    • Applied Chemistry for Engineering
    • /
    • v.10 no.4
    • /
    • pp.599-602
    • /
    • 1999
  • Chitosan was depolymerized by using nitrous acid. In order to synthesize new fluorinated chitosan oligomer(FCO) derivative, free amine groups of resulting low molucular weight chitosan oligomers were reacted with trifluoroacetic anhydride. The structure changes in the samples were conformed by using FT-IR, $^{1}H\;NMR$, $^{13}C\;NMR$ and $^{19}F\{^{1}H\}NMR$. Antiviral activity of FCO was studied by measuring DAN amounts of the replication viruses at 36 hr after the cells were infected with the viral solution containing FCO of various concentrations. The viral replications in the cells infected with the viral solution containing FCO were proportionally decreased with the FCO does, compared to those of the control groups, indicating that FCO efficiently inhibits viral infection. In particular, viral replication was decreased to 40% in the 1% FCO-treated cells.

  • PDF

Genetic Diversity and Variation of Chinese Shrimp Fenneropenaeus chinensis Populations as Inferred by AFLP Fingerprinting (대하 Fenneropenaeus chinensis 집단의 AFLP 지문에 의한 유전 다양성 및 변이)

  • Sung, Yong-Gil;Nam, Yoon-Kwon;Han, Hyeon-Seob;Bang, In-Chul
    • Journal of Aquaculture
    • /
    • v.20 no.4
    • /
    • pp.255-259
    • /
    • 2007
  • Genetic diversity among four populations of Chinese shrimp Fenneropenaeus chinensis from Narodo, Yeonggwang, Taean and Chinese Bohai Bay was assessed by amplified fragment length polymorphism (AFLP) DNA fingerprinting. Total numbers of AFLP bands generated (ranging from 251 to 254) and average percent of polymorphic bands (27.1 to 28.1 %) were similar in the four populations. Heterozygosity and genetic diversity within or among the populations were very low for the populations with average values ranging from 0.1177 to 0.1288 and from 0.1099 to 0.1194, respectively. Analyses of pairwise distance, Fst index and genetic similarity among the populations also revealed the similar results with very low genetic differentiation each other. These results suggest that all the wild populations tested in the present analysis may be belonging to the same genetic origin, and also that they may have a close relationship in genetic structure without any significant differentiation.

A Comparative Genome-Wide Analysis of GATA Transcription Factors in Fungi

  • Park, Jong-Sun;Kim, Hyo-Jeong;Kim, Soon-Ok;Kong, Sung-Hyung;Park, Jae-Jin;Kim, Se-Ryun;Han, Hyea-Young;Park, Bong-Soo;Jung, Kyong-Yong;Lee, Yong-Hwan
    • Genomics & Informatics
    • /
    • v.4 no.4
    • /
    • pp.147-160
    • /
    • 2006
  • GATA transcription factors are widespread eukaryotic regulators whose DNA-binding domain is a class IV zinc finger motif in the form $CX_{2}CX_{17-20}CX_{2}C$followed by a basic region. In fungi, they act as transcriptional activators or repressors in several different processes, ranging from nitrogen source utilization to mating-type switching. Using an in-house bioinformatics portal system, we surveyed 50 fungal and 9 out-group genomes and identified 396 putative fungal GATA transcription factors. The proportion of GATA transcription factors within a genome varied among taxonomic lineages. Subsequent analyses of phylogenetic relationships among the fungal GATA transcription factors, as well as a study of their domain architecture and gene structure, demonstrated high degrees of conservation in type IVa and type IVb zinc finger motifs and the existence of distinctive clusters at least at the level of subphylum. The SFH1 subgroup with a 20-residue loop was newly identified, in addition to six well-defined subgroups in the subphylum Pezizomycotina. Furthermore, a novel GATA motif with a 2f-residue loop ($CX_{2}CX_{21}CX_{2}C$, designated 'zinc finger type IVc') was discovered within the phylum Basidiomycota. Our results suggest that fungal GATA factors might have undergone multiple distinct modes of evolution resulting in diversified cellular modulation in fungi.

Characterization of Heterologously Expressed Acetyl Xylan Esterase1 Isolated from the Anaerobic Rumen Fungus Neocallimastix frontalis PMA02

  • Kwon, Mi;Song, Jaeyong;Park, Hong-Seog;Park, Hyunjin;Chang, Jongsoo
    • Asian-Australasian Journal of Animal Sciences
    • /
    • v.29 no.11
    • /
    • pp.1576-1584
    • /
    • 2016
  • Acetyl xylan esterase (AXE), which hydrolyzes the ester linkages of the naturally acetylated xylan and thus known to have an important role for hemicellulose degradation, was isolated from the anaerobic rumen fungus Neocallimastix frontatlis PMA02, heterologously expressed in Escherichi coli (E.coli) and characterized. The full-length cDNA encoding NfAXE1 was 1,494 bp, of which 978 bp constituted an open reading frame. The estimated molecular weight of NfAXE1 was 36.5 kDa with 326 amino acid residues, and the calculated isoelectric point was 4.54. The secondary protein structure was predicted to consist of nine ${\alpha}$-helixes and 12 ${\beta}$-strands. The enzyme expressed in E.coli had the highest activity at $40^{\circ}C$ and pH 8. The purified recombinant NfAXE1 had a specific activity of 100.1 U/mg when p-nitrophenyl acetate (p-NA) was used as a substrate at $40^{\circ}C$, optimum temperature. The amount of liberated acetic acids were the highest and the lowest when p-NA and acetylated birchwood xylan were used as substrates, respectively. The amount of xylose released from acetylated birchwod xylan was increased by 1.4 fold when NfAXE1 was mixed with xylanase in a reaction cocktail, implying a synergistic effect of NfAXE1 with xylanase on hemicellulose degradation.

Effects of Acute Lymphoblastic Leukemia on Ceruloplasmin Oxidase, Copper and Several Markers of Oxidative Damage, in Children

  • Mehdi, Wesen Adel;Yusof, Faridah;Mehde, Atheer Awad;Zainulabdeen, Jwan Abdulmohsin;Raus, Raha Ahmed;Abdulbari, Alaa Shawqi
    • Asian Pacific Journal of Cancer Prevention
    • /
    • v.16 no.13
    • /
    • pp.5205-5210
    • /
    • 2015
  • Background: Acute leukaemia is characterized by fast growth of abnormal clones of haemopoietic precursor cells inside bone marrow leading to undue accumulation in the bone marrow. Acute lymphoblastic leukemia (ALL) is the most common form of childhood cancer. Materials and Methods: The study concerned 50 children diagnosed with ALL (mean age, $8.55{\pm}2.54$) compared to 40 healthy controls (mean age, $8.00{\pm}1.85$). The Hb, serum copper, ceruloplasmin oxidase, advanced oxidation protein products (AOPPs), total antioxidant activity (TAA) and protein were measured in all groups.One proteinous component was isolated by gel filtration chromatography from the precipitate produced by polyethylene glycol. Results: Significantly higher levels of AOPP, copper and decrease in total antioxidant activity were noted in the cases. Statistical analysis also showed a significant increase (p<0.01) in the activity of serum ceruloplasmin oxidase in patients with ALL compared to normal subjects .The maximum velocity (Vmax) and Michaelis constant had values of 104.2 U/L and 11.7 mM, respectively. The ${\Delta}H^*$ values for ceruloplasmin oxidase in ALL patients were positive, confirming the reaction to be endothermic. Conclusions: The results from this study showed a significant increase in AOPP, ceruloplasmine oxidase and decrease in total antioxidant activity .These parameters may play a role in development of DNA damage in childhood patients with acute lymphoblastic leukemia (ALL).The ${\Delta}S^*$ and ${\Delta}G^*$ values were negative, these refer that the reaction of ES formation is spontaneous, but needs energy in a so-called endergonic reaction. Also the negative ${\Delta}S^*$ value of ceruloplasmin oxidase indicates that the complex [$ES^*$] is further modulated through increasing structure arrangement.

Expression Vectors for Human-mouse Chimeric Antibodies

  • Xiong, Hua;Ran, Yuliang;Xing, Jinliang;Yang, Xiangmin;Li, Yu;Chen, Zhinan
    • BMB Reports
    • /
    • v.38 no.4
    • /
    • pp.414-419
    • /
    • 2005
  • The production of recombinant antibodies has been generally recognized as time-consuming and labor-intensive. The aim of our study is to construct mammalian expression vectors containing the cDNA encoding the human constant regions and murine variable regions to massively and cost-effectively produce full-length chimeric antibodies. Unique restriction sites flanking the Ig variable region were designed to allow for the replacement of variable regions generated by PCR. Western blot analysis of the chimeric antibodies revealed that the expressed products were of the predicted size, structure and specificity. The usefulness of the vectors was confirmed by construction of human-mouse chimeric antibody-HCAb which secretes murine antibody against the human colorectal cancer. Selected in medium containing gradually increasing methotrexate (MTX), clones with increased expression of the product gene can be efficiently generated. The secretion of recombinant chimeric antibody-HCAb yielded $30\;pg\;cell^{-1}\;day^{-1}$ at $10^{-6}\;M$ MTX. With this high-level expression from pools, the convenient and rapid production of over 100 milligram amounts per liter of recombinant antibodies may be achieved, which indicates the significant roles of pYR-GCEVH and pYR-GCEVL in the production of chimeric antibodies.

Effects of Magnetic Pole on Orientation of Bull Sperm Treated by Dithiothreitol or Heparin

  • Pham, Du Ngoc;Shinjo, Akihisa;Kurnianto, Edy
    • Asian-Australasian Journal of Animal Sciences
    • /
    • v.14 no.2
    • /
    • pp.155-162
    • /
    • 2001
  • Effect of the north (N) or south pole (S) of a magnet and dithiothreitol (DTT) or heparin sodium (H) on the orientation of bull sperm were studied. Sperm were collected from four Japanese Black bulls of Okinawa Prefectural Livestock Experimental Station were treated with various concentrations of DTT or H during the first and sixth days and were then exposed them to N or S with a magnetic field of 3,000 Gauss for 24 hours. Experimental results showed that both N and S significantly increased the perpendicular oriented percentage of bull sperm in most treatments not treated or treated with DTT or H. Anisotropy of magnetic field of bull sperm was the main cause which induced them to orient perpendicular to the magnetic direction. The results of the experiment also showed that, in most cases, the two polarities had the same effect on the orientation of bull sperm. However, in some cases, N exerted a stronger effect on the perpendicular percentage of bull sperm than S, such as with the 20 mM DTT treatment at the first and sixth days and the 100 units H treatment at the sixth day. These cases showed that the perpendicular oriented percentage of bull sperm at N was significantly higher than that of S. It was only the 100 units heparin treatment at S both at the first and sixth days that upward perpendicular orientation was higher than that at N. This might be due to the fact that protamin-DNA structure of a small number of bull sperm nuclei slightly changed because of heparin action.

Nosema sp. isolated from Cabbage White Butterfly(Pieris rapae) Collected in Korea

  • Park, Ji-Young;Kim, Jong-Gill;Park, Young-Cheol;Goo, Tae-Won;Chang, Jin-Hee;Je, Yeon-Ho;Kim, Keun-Young
    • Journal of Microbiology
    • /
    • v.40 no.3
    • /
    • pp.199-204
    • /
    • 2002
  • A microsporidium, from cabbage white bntteflies, Pieris rapae, collected in Korea, was purified and characterized according to its gene structure, spore morphology and pathogenicity. From the observation of the isolate by SEM and TEM, the endospores, exospores and nuclei, about 12 polar filament coils of the polar tube and posterior vacuoles were all identified. The nucleotide sequence was determined for a portion of genomic DNA which spans the V4 variable region of the small subunit rRNA gene. Comparison with the GenBank database for 15 other microsporidia species suggests that this isolate is most closely related to Nosema species. The pathogenicity against cabbage white butterflies was quantified by inoculating variable doses of spores to the second instar larvae. Peroral inoculation at a dosage of 10$\^$8/ spores/ml resulted in the death of all larvae prior to adult eclosion, but at lower spore dosages of 10$\^$4/-10$\^$5/ spores/ml, many adults successfully emerged. The median lethal dose (LD$\_$50/) was deter-mined to be 4.6$\times$10$\^$6/ spores/ml and the isolate also transmitted transovarially to the progeny eggs at a frequency of 92%.

Generation of Protein Lineages with new Sequence Spaces by Functional Salvage Screen

  • Kim, Geun-Joong;Cheon, Young-Hoon;Park, Min-Soon;Park, Hee-Sung;Kim, Hak-Sung
    • Proceedings of the Korean Society for Applied Microbiology Conference
    • /
    • 2001.06a
    • /
    • pp.77-80
    • /
    • 2001
  • A variety of different methods to generate diverse proteins, including random mutagenesis and recombination, are currently available, and most of them accumulate the mutations on the target gene of a protein, whose sequence space remains unchanged. On the other hand, a pool of diverse genes, which is generated by random insertions, deletions, and exchange of the homologous domains with different lengths in the target gene, would present the protein lineages resulting in new fitness landscapes. Here we report a method to generate a pool of protein variants with different sequence spaces by employing green fluorescent protein (GFP) as a model protein. This process, designated functional salvage screen (FSS), comprises the following procedures: a defective GFP template expressing no fluorescence is firstly constructed by genetically disrupting a predetermined region(s) of the protein, and a library of GFP variants is generated from the defective template by incorporating the randomly fragmented genomic DNA from E. coli into the defined region(s) of the target gene, followed by screening of the functionally salvaged, fluorescence-emitting GFPs. Two approaches, sequence-directed and PCR-coupled methods, were attempted to generate the library of GFP variants with new sequences derived from the genomic segments of E. coli. The functionally salvaged GFPs were selected and analyzed in terms of the sequence space and functional property. The results demonstrate that the functional salvage process not only can be a simple and effective method to create protein lineages with new sequence spaces, but also can be useful in elucidating the involvement of a specific region(s) or domain(s) in the structure and function of protein.

  • PDF