Prokaryotic expression, subcellular localization and enzymatic activity analysis of DXS gene from Platycodon grandiflorum / 药学学报

1-Deoxy-D-xylulose-5-phosphate synthase (DXS), the first key enzyme in 2-methyl-D-erythritol-4-phosphate (MEP) pathway, catalyzes the condensation of glyceraldehyde-3-phosphate with pyruvate to 1-deoxy-xylose-5-phosphate (DXP). In this study, PgDXS1, PgDXS2, and PgDXS3 genes were cloned from the root of Platycodon grandiflorum (P. grandiflorum). The open reading frame (ORF) of PgDXS1, PgDXS2, and PgDXS3 were 2 160, 2 208, and 2 151 bp in full length, encoding 719, 735, and 716 amino acids, respectively. Homologous alignment results showed a high identity of PgDXSs with DXS in Hevea brasiliensis, Datura stramonium and Stevia rebaudiana. The recombinant expression plasmids of pET-28a-PgDXSs were constructed and transformed into Escherichia coli (E. coli) BL21 (DE3) cells, and the induced proteins were successfully expressed. Subcellular localization results showed that PgDXS1 and PgDXS2 were mainly located in chloroplasts, and PgDXS3 was located in chloroplasts, nucleus and cytoplasm. The expression of three DXS genes in different tissues of two producing areas of P. grandiflorum were assayed via real-time fluorescence quantitative PCR, and the results showed that all of them were highly expressed in leaves of P. grandiflorum from Taihe. Under methyl jasmonate (MeJA) treatment, the expression levels of three PgDXS genes showed a trend of first decreasing and then increasing at different time points (3 - 48 h), and the activity of DXS showed a trend of first increasing and then decreasing in three tissues of P. grandiflorum. This study provides a reference for further elucidating the biological function of PgDXS in terpenoid synthesis pathway in P. grandiflorum.

Cloning and prokaryotic expression of 3-ketoacyl-CoA thiolase gene AIKAT from Atractylodes lancea / 中国中药杂志

In this study, the gene encoding the key enzyme 3-ketoacyl-CoA thiolase(KAT) in the fatty acid β-oxidation pathway of Atractylodes lancea was cloned. Meanwhile, bioinformatics analysis, prokaryotic expression and gene expression analysis were carried out, which laid a foundation for the study of fatty acid β-oxidation mechanism of A. lancea. The full-length sequence of the gene was cloned by RT-PCR with the specific primers designed according to the sequence information of KAT gene in the transcriptomic data of A. lancea and designated as AIKAT(GenBank accession number MW665111). The results showed that the open reading frame(ORF) of AIKAT was 1 323 bp, encoding 440 amino acid. The deduced protein had a theoretical molecular weight of 46 344.36 and an isoelectric point of 8.92. AIKAT was predicted to be a stable alkaline protein without transmembrane segment. The secondary structure of AIKAT was predicted to be mainly composed of α-helix. The tertiary structure of AIKAT protein was predicted by homology modeling method. Homologous alignment revealed that AIKAT shared high sequence identity with the KAT proteins(AaKAT2, CcKAT2, RgKAT and AtKAT, respectively) of Artemisia annua, Cynara cardunculus var. scolymus, Rehmannia glutinosa and Arabidopsis thaliana. The phylogenetic analysis showed that AIKAT clustered with CcKAT2, confirming the homology of 3-ketoacyl-CoA thiolase genes in Compositae. The prokaryotic expression vector pET-32 a-AIKAT was constructed and transformed into Escherichia coli BL21(DE3) for protein expression. The target protein was successfully expressed as a soluble protein of about 64 kDa. A real-time quantitative PCR analysis was performed to profile the AIKAT expression in different tissues of A. lancea. The results demonstrated that the expression level of AIKAT was the highest in rhizome, followed by that in leaves and stems. In this study, the full-length cDNA of AIKAT was cloned and expressed in E. coli BL21(DE3), and qRT-PCR showed the differential expression of this gene in different tissues, which laid a foundation for further research on the molecular mechanism of fatty acid β-oxidation in A. lancea.

Different development phase of transcriptome analysis from Crataegus pinnatifida Bge. and cloning, structure and function prediction of squalene epoxidase involved in triterpenic acid biosynthesis / 药学学报

italic>Crataegus pinnatifida is a traditional Chinese medicine, which contains organic acids, triterpenoid acids and other active components, has important medicinal and edible value. In order to study the difference of gene expression level in different developmental stages of hawthorn and explore the genes of active ingredient biosynthesis in Crataegus pinnatifida, high-throughput Illumina HiSeq 2000 technology were used to conduct transcriptome sequencing and bioinformatics analysis on Crataegus pinnatifida fruits from the same origin at different developmental stages. 78 496 Unigenes with an average length of 941 nt were obtained by Trinity software. Among them, 58 395 Unigenes can be annotated by NR, NT, Swiss prot, KEGG, COG, GO and other public databases. KEGG pathway analysis showed that 52 Unigenes encoding 15 key enzymes involved in the citric acid cycle. There are 62 Unigenes were involved in the triterpene biosynthesis pathway of Crataegus pinnatifida. Two key enzymes SQE of triterpenoid metabolism pathway in Crataegus pinnatifida were cloned and performed bioinformatic analysis. The results showed that ORF of CpSQE1 and CpSQE2 were 1 594 bp and 1 597 bp, respectively, encoding 530 and 531 amino acids. The molecular weight of proteins was 57.6 kDa and 57.5 kDa. Bioinformatics analysis showed that both CpSQE1 and CpSQE2 proteins have a PLN02985 superfamily conserved domain, belonging to the squalene monooxygenase superfamily. The phylogenetic tree shows that CpSQE1 and CpSQE2 are clustered together with SQE with squalene epoxidase function in other plants. This study provides a research basis for further exploring the key genes in the biosynthesis process of hawthorn active ingredients and analyzing the regulation pathway of its active ingredient biosynthesis.

Identification and analysis of the rare HLA-A/B/DRB1 allele genes of 10165 bone marrow registry donors in Shaanxi region / 中国实验血液学杂志

This study was purposed to analyze the detected status of rare alleles from HLA-A/B/DRB1 typing of 10165 unrelated hematopoietic stem cell donors in Shaanxi region during 2009-2012. The rare allele distributions of HLA-A/B/DRB1 gene typing of 10165 unrelated-donors from Shaanxi sub-registry of Chinese National Marrow Donor Project (CMDP) were detected and analyzed by PCR-SBT. The results showed that there were 40 rare alleles from 48 donors identified by PCR-SBT in 10165 unrelated-donors of Shaanxi sub-registry. Among them, 10 rare alleles of A*02:04, B*07:10, B*27:09, B*35:11, B*44:29, DRB1*03:04, DRB1*08:18, DRB1*13:05, DRB1*13:14 and DRB1*14:11 from 15 donors were not included in the common alleles and well documented alleles (CWD) of China, but were included in the CWD of American Society for Histocompatibility and Immunogenetics (ASHI). The alleles of A*68:24, B*35:11, B*44:29, DRB1*03:04, DRB1*08:18 and DRB1*13:05 were confirmed in more than two samples. There were totally 21 novel HLA alleles identified by our laboratory and officially assigned by the WHO Nomenclature Committee from 2005 to 2012, and some of them were also detected from multiple donors in other HLA typing laboratories of China. Now the novel alleles of HLA-A*02:90, HLA-B*48:14 and HLA-DRB1*01:14 were added into the Chinese CWD list. It is concluded that to ensure the polymorphism integrity and accurate population distribution of HLA genes and its constant accumulations on CMDP, it is necessary to recognize and submit timely the potential novel alleles in our practical work, as well as to record and statistics the identified rare alleles, which can provide the basis for the modification of Chinese CWD. When CWD list is referred, it should be careful for ambiguous results containing the identified rare alleles in order to avoid the occurrence of false or undiscovered detection, and ensure that the patients carrying rare alleles could find a matching donor with the maximum opportunity.

Analysis of gene polymorphism of HPA and HLA-I in Chinese Xi'an voluntary platelet donors / 中国实验血液学杂志

To study the allele frequencies and their polymorphism characteristics of human platelet antigen (HPA) and human leucocyte antigen-I (HLA-I) in Chinese xi'an population, the types of HPA and HLA-I in 375 Chinese xi'an voluntary platelet donors were detected by PCR-SSP and PCR-SSO as well as flow cytometry with magnetic beads, and were analyzed. The results showed that there was no polymorphism in HPA-7-HPA-14, HPA-16 and HPA-17 which only expressed-aa type, the -bb type was only detected in HPA-3 and HPA-15, 9 out of 16 samples for the HPA-5ab phenotype simultaneously expressed HPA-15ab, the other 7 samples expressed HPA-15bb, no HPA-15aa phenotype was observed. Phenotypes detected in this study were HPA-1aa-17aa, HPA-1ab, -2ab, -3ab, -3bb, -4ab, -5ab, -6ab, -15ab and -15bb. Among 375 cases, HLA-A specificity of 16 species was observed, which accounted for 76% (16/21) of detectable phenotype specificity in this locus, moreover, 11 species showed frequency > 1%; HLA-B specificity of 36 species was observed which accounted for 84% (36/43) of detectable phenotype specificity in this locus, moreover 23 species showed frequency > 1%, these species were covered by common specific HLA-I in northern China, 264 species haplotype HLA-A-B were found in 375 cases, the frequency of 30 species was > 1%. It is concluded that the gene frequency distribution of HPA and HLA-I in Chinese Xi'an population is in accordance with population of northern China on the whole, but it has its own characteristics.

Molecular study of two novel RHD alleles and pedigree analysis / 中华医学遗传学杂志

<p><b>OBJECTIVE</b>To study the segregation of two novel RHD alleles in Chinese pedigrees.</p><p><b>METHODS</b>The Rh antigens of the samples were identified by using monoclonal antibodies. The 10 exons of the RHD gene for the 2 probands and their family members were amplified separately and sequenced. The parents of proband 2 were analyzed by sequence specific primer-polymerase chain reaction (SSP-PCR).</p><p><b>RESULTS</b>The two probands were RhD negative and the RHD was D/d type. After alignment with the nucleotide sequence in GenBank, a deletion of nucleotide C at position 78 in exon 1 of proband 1 was detected, and her sister also had the deletion, which was confirmed by sequencing. The sequencing results of proband 2 showed a 10 nucleotide deletion in exon 8 as well as a RHD 520 G to A mutation in exon 4. The results of SSP-PCR and sequencing showed that the proband's mother also carried RHD 520 G to A and RHD 1080 del 10 mutation, which was transmitted to proband 2. The sequences of the novel alleles have been submitted to GenBank (accession No. GQ477180 and GU362076).</p><p><b>CONCLUSION</b>The two novel RHD alleles, RHD 78delC and RHD 520 G to A+1080 del 10, were both pseudo genes and stably transmitted.</p>

Cumulation and effect of chemokines and CD40L during blood storage--review / 中国实验血液学杂志

Chemokine is a class of soluble active peptides that attract white blood cells to the inflammatory site. CD40 ligand (CD40L) involves in synthesis of proinflammatory mediators. Accumulation of chemokine and CD40L can induce non-hemolytic reaction after transfusion, transfusion-related acute lung injury (TRALI) and autoimmune disease during blood component storage. Pre-storage leucocyte deletion can prevent the release of leucocyte-derived chemokines, but not prevent the accumulation of platelet-derived chemokines. γ-irradiation or ultraviolet β irradiation is effective in preventing the increase of chemokines in the storage of platelet, thus prevents non-hemolytic febrile reaction after platelet transfusion. In this review, the recent advance in research of accumulation of chemokines and CD40L during blood component storage, and its effect on blood transfusion, as well as preventive measures are summarized.

Transfusion-associated microchimerism -- review / 中国实验血液学杂志

Blood transfusion is a newly recognized cause of microchimerism, it seems to be common in severe traumatic injuries. In this review, the frequency, cause and prevention of transfusion-associated microchimerism (TA-MC), its current progress of knowledge and unanswered questions were summarized. In addition, the pregnancy-associated microchimerism and transplantation-associated microchimerism were discussed in this review.

HLA-B*15 gene polymorphism of registered bone marrow from donors in north Chinese Han population typed by PCR-SBT / 中国实验血液学杂志

To investigate the characteristics of the allele distribution of HLA-B*15 gene family in Chinese Han population and to study its influence on the selection of clinical transplantation donor, population of a 815 Han in north China from Shaanxi sub-registry of Chinese National Marrow Donor Project was randomly selected and out of them 206 HLA-B*15 positive samples according to the previous known low-resolution typing results were acquired. HLA-B*15 gene polymorphisms of above-mentioned samples and other 17 individuals were analyzed for the first time by polymerase chain reaction sequence-based typing (PCR-SBT) at high-resolution level. The structure differentiation of all HLA-B*15 alleles were analyzed by HLA three-dimensional structure modeling and software Swiss-PdbViewer. The results showed that the distribution of HLA-A, -B, -DRB1 gene of randomly selected 815 samples accorded with Hardy-Weinberg equilibrium and the gene frequency of HLA-B*15 was 0.1379. There were a total of 16 kinds of alleles of HLA-B*15 gene family to be obtained, which belonged to 7 kinds of serologic specificities. HLA-B*1501, B*1511, B*1502 and B*1518 were the major alleles with a frequency of 0.0485, 0.0215, 0.0178 and 0.0160 respectively, and the constituent ratio of their accumulated frequencies was 75.11%. The each frequency of the other 12 kinds of B*15 alleles was lower than 0.0100. Among the homozygote of 10 samples at low/medial-resolution level, there were only 4 samples to be pur sang homozygote of HLA-B*15xx, --at high-resolution level, and all the homozygote were constituted by respective dominating alleles. HLA three-dimensional structure modeling demonstrated that within the same specificity, gentle structure differentiation not only existed, such as B*1501, 1505, 1507, 1525, 1527, 1532 (each RMSD<or=0.02 nm), but also presented significant structure differentiation, such as B*1502, 1511, 1521 and B*1503, 1546 (each RMSD=0.29 nm). However, some alleles belonged to different specificities showed similar structure with RMSD<or=0.02 nm. It is concluded that the characteristics of HLA-B*15 gene polymorphism defined by PCR-SBT with the largest sample size up to now is unique in north Chinese Han population. The study will be helpful to find suitable donors for patients and establish the important foundation for further studying transplantation immunity and population genetics in this area. To select the optimal donor, it is necessary for gene family with high polymorphism like HLA-B*15 to type accurately at high-resolution level.

Gene and haplotype frequencies for the loci HLA-A, B and DRB1 in 11755 north Chinese Han bone marrow registry donors / 中国实验血液学杂志

The study was aimed to investigate the human leukocyte antigen (HLA)-A, B, DRB1 alleles and haplotype frequencies and the characteristics of linkage disequilibrium in north Chinese Han bone marrow donors. HLA phenotype data of 11 755 north Chinese Han bone marrow donors were identified by PCR-SSP and PCR-SSO. HLA-A, B, DRB1 allele and haplotype frequencies were calculated by computer software named Arleguin which was based on Expectation-Maximization (EM) algorithms. The results showed that the population of 11755 unrelated-donors was tested by Hardy-Weinberg equilibrium, and 18,42 and 15 specificities of HLA alleles were identified on the HLA-A, B, DRB1 locus respectively, including HLA-A25, B42, B53, B73 and DR3 which were rarely reported in Han population. HLA-A36, A43, A80, B78, B82 and DR18 were not detected in this study. The most frequent alleles with a frequency of over 0.05 were HLA-A*02, A*11, A*24, A*33, A*30, A*01, A*03, A*13, B62, B*51, B*46, B60, B61, B*35, B*44, DRB1*15, DRB1*09, DRB1*04, DRB1*07, DRB1*12, DRB1*11, DRB1*14, DRB1*08, DRB1*13. There were a total of 2 026 kinds of HLA-A-B-DR haplotypes (with a frequency of over 10(-6)) to be obtained. The each frequency of 26 kinds of three-locus haplotypes including HLA-A30-B13-DR7, A2-B46-DR9, A33-B58-DR17 etc was higher than 0.005. A30-B13-DR7 was the most frequent haplotype in north Chinese Han population. There were a total of 538 kinds of haplotypes for HLA-A-B, 227 kinds for A-DR and 522 kinds for B-DR to be obtained, and there were 409, 195, 423 kinds of haplotypes respectively with a frequency higher than 10 - 6. There were 28 kinds of HLA-A-B haplotypes including A30-B13, A2-B46, A33-B58 etc, 26 kinds of HLA-A-DR haplotypes including A2-DR9, A2-DR15, A30-DR7 etc, and 24 kinds of HLA-B-DR haplotypes including B13-DR7, B46-DR9, B13-DR12 etc with a frequency higher than 0.01. 296 (72%) kinds of HLA-A-B, 130 (67%) kinds of A-DR and 308 (73%) kinds of B-DR haplotypes were statistical linkage disequilibrium. HLA-A30-B13, A33-B58, A1-B37, A30-DR7, A33-DR13, A1-DR10, B37-DR10, B8-DR17, B13-DR7, B58-DR17 were significant positive linkage disequilibrium. It is concluded that this HLA-A, B, DRB1 gene and haplotype frequencies and linkage disequilibrium data with the largest sample size up to now is unique in north Chinese Han population. The study will be helpful to find matched donors for patients and establish the important foundation for further studying of transplantation immunity, HLA-related diseases and population genetics of this area.