ABSTRACT
Cinnamomumparthenoxylon is an endemic and endangered species with significant economic and ecological value in Vietnam. A better understanding of the genetic architecture of the species will be useful when planning management and conservation. We aimed to characterize the transcriptome of C.parthenoxylon, develop novel molecular markers, and assess the genetic variability of the species. First, transcriptome sequencing of five trees (C.parthenoxylon) based on root, leaf, and stem tissues was performed for functional annotation analysis and development of novel molecular markers. The transcriptomes of C.parthenoxylon were analyzed via an Illumina HiSeqTM 4000 sequencing system. A total of 27,363,199 bases were generated for C.parthenoxylon. De novo assembly indicated that a total of 160,435 unigenes were generated (average length = 548.954 bp). The 51,691 unigenes were compared against different databases, i.e. COG, GO, KEGG, KOG, Pfam, Swiss-Prot, and NR for functional annotation. Furthermore, a total of 12,849 EST-SSRs were identified. Of the 134 primer pairs, 54 were randomly selected for testing, with 15 successfully amplified across nine populations of C.parthenoxylon. We uncovered medium levels of genetic diversity (PIC = 0.52, Na = 3.29, Ne = 2.18, P = 94.07%, Ho = 0.56 and He = 0.47) within the studied populations. The molecular variance was 10% among populations and low genetic differentiation (Fst = 0.06) indicated low gene flow (Nm = 2.16). A reduction in the population size of C.parthenoxylon was detected using BOTTLENECK (VP population). The structure analysis suggested two optimal genetic clusters related to gene flow among the populations. Analysis of molecular variance (AMOVA) revealed higher genetic variation within populations (90%) than among populations (10%). The UPGMA approach and DAPC divided the nine populations into three main clusters. Our findings revealed a significant fraction of the transcriptome sequences and these newlydeveloped novel EST-SSR markers are a very efficient tool for germplasm evaluation, genetic diversity and molecular marker-assisted selection in C.parthenoxylon. This study provides comprehensive genetic resources for the breeding and conservation of different varieties of C.parthenoxylon.
ABSTRACT
Constant pressure simulations were carried out to construct a new rigid nonpolarizable seven-site water model (TIP7P), which is an effective and efficient version of flexible seven-fluctuating-charge water model. In this model, the positive charges are located on three nuclei and the negative charges disperse on two bond sites at the geometric center of each OH bond and two lone-pair sites along the tetrahedral direction away from the oxygen atom. Our new model performs better than other models in properties, such as radial distribution function, liquid density, thermal expansion coefficient, isothermal compressibility, vaporization enthalpy, isobaric heat capacity, static dielectric constant, self-diffusion coefficient, critical temperature, and density. This model reproduces liquid density and static dielectric constant over the temperatures from 253 to 373 K at 1 atm with the standard deviation of 0.0010 g/cm3 and 1.37 to the experimental data, respectively. The maximum density is 1.0006 g/cm3 at 277 K. The calculated isobaric compressibility presents a minimum at about 310 K close to the experimental value of 319 K. The self-diffusion coefficient agrees the experimental data with the standard deviation of 0.55 × 10-5 cm2/s, although it is not the target property for parameterization. Liquid-vapor phase equilibrium was examined in slab simulations. The evaluated critical temperature and density are 633 K and 0.337 g/cm3 close to the experimental values of 647.096 K and 0.322 g/cm3. This model also presents reasonable vaporization enthalpy and isobaric heat capacity. Based upon good performances mentioned, our new model is a good choice for more accurate investigation to large molecular systems.
ABSTRACT
Objective To construct lentiviral vectors containing peptide P1-GFP fusion genes.Umbilical cord derived mesenchymal stem cells were infected with lentivirus carrying peptide P1 and GFP fusion genes.To inject the targeted umbilical cord derived mesenchymal stem cells into mice and to detect GFP expression in the spleen.Methods Umbilical cord derived mesenchymal stem cells were cultured with adhered tissues of umbilical cord smaller than 1 mm3 . Lentiviral vector containing P1-GFP fusion genes with engineering technology was constructed and infected the umbilical cord derive mesenchymal stem cells.Targeted umbilical cord derived mesenchymal stem cells were intravenously injected in the mouse tail vein and after 18 hours GFP expression was detected with immunohistochamical staining of the spleen tissues.Results Harvested umbilical cord derived mesenchymal stem cells grew well in culture medium. Green fluorescence on umbilical cord derived mesenchymal stem cells were observed under fluorescence microscope at 18 hours after infected with lentivirus.Green fluorescence intensity of umbilical cord derived mesenchymal stem cells was increasing over time and reached a peak at 72 hours.Umbilical cord derived mesenchymal stem cells highly expressed CD105 (90.0%)/CD44 (98%) and CD73 (85.0%)/CD90 (98.5%) molecules.GFP expression was detected in the spleen after intravenous injection of targeted umbilical cord derived mesenchymal stem cells in the mice 18 hours later.GFP expressing cells intimately contacted with lymphocytes.Conclusions Targeted umbilical cord derived mesenchymal stem cells contain P1-GFP fusion genes are constructed.Targeted umbilical cord derived mesenchymal stem cells can be targeted to mouse spleen and intimately contact with lymphocytes after intravenous injection.Our results lay the groundwork for further studies.
