PubMed Health⌕ Search

Biomedical subjects

Shu-Hong Zhao

Publications and source records attributed to Shu-Hong Zhao.

7 recordsLinked to original sources

Gene expression profiling in Salmonella Choleraesuis-infected porcine lung using a long oligonucleotide microarray.

Understanding the transcriptional response to pathogenic bacterial infection within food animals is of fundamental and applied interest. To determine the transcriptional response to Salmonella enterica serovar Choleraesuis (SC) infection, a 13,297-oligonucleotide swine array was used to analyze RNA from control, 24-h postinoculation (hpi), and 48-hpi porcine lung tissue from pigs infected with SC. In total, 57 genes showed differential expression (p < 0.001; false discovery rate = 12%). Quantitative real-time PCR (qRT-PCR) of 61 genes was used to confirm the microarray results and to identify pathways responding to infection. Of the 33 genes identified by microarray analysis as differentially expressed, 23 were confirmed by qRT-PCR results. A novel finding was that two transglutaminase family genes (TGM1 and TGM3) showed dramatic increases in expression postinoculation; combined with several other apoptotic genes, they indicated the induction of apoptotic pathways during SC infection. A predominant T helper 1-type immune response occurred during infection, with interferon gamma (IFNG) significantly increased at 48 hpi. Genes induced by IFNs (GBP1, GBP2, C1S, C1R, MHC2TA, PSMB8, TAP1, TAP2) showed increased expression during porcine lung infection. These data represent the first thorough investigation of gene regulation pathways that control an important porcine respiratory and foodborne bacterial infection.

Animals↗

Transcriptional profiling using a novel cDNA array identifies differential gene expression during porcine embryo elongation.

A novel porcine cDNA array, containing 1,015 PCR products selected for embryonic expression, was used for transcriptional profiling of conceptuses at four stages of peri-implantation development. Total conceptus RNA from small spherical, large spherical, tubular, and filamentous stages was amplified, converted to cDNA, and hybridized to membranes. Initially, normalized signal intensities obtained using cDNA from total RNA or from amplified RNA were compared. Uniform distribution of P-values associated with t-tests conducted for each gene indicated no evidence that amplification introduced bias. Analysis of data obtained by using amplified targets and the novel array identified genes differentially expressed across stages. Such genes were identified by testing for significant stage effects in gene-specific mixed models. A total of nine genes were declared differentially expressed. Six of the nine genes had P-values less than 0.001, and a false discovery rate of approximately 17% was associated with this significance threshold. Two out of six genes were significant when using the Bonferroni method to control the probability of one or more false positives. The other three genes had P-values between 0.001 and 0.01 and exhibited differences greater than twofold between stages. All four genes selected for confirmation (steroidogenic acute regulatory protein, interleukin 1 beta, transforming growth factor beta 3, and thymosin beta 10) were shown to be differentially expressed by using quantitative real time RT-PCR. Our study shows that RNA amplification is useful for transcriptional profiling with limiting porcine embryonic RNA, and that this novel targeted array can detect differential gene expression during trophoblastic elongation. Finally, our results contribute to an increased understanding of the temporal patterns of expression of known genes controlling conceptus development, as well as identify novel genes also differentially regulated during implantation.

Animals↗

Validation of a first-generation long-oligonucleotide microarray for transcriptional profiling in the pig.

A first-generation porcine oligonucleotide set, representing 13,297 cDNAs and ESTs, has been designed by Qiagen-Operon for transcriptional profiling. To validate this set, microarrays containing each 70-mer oligonucleotide, referred to as the Qiagen-NRSP8 array, were hybridized with targets from porcine adult liver, lung, muscle, or small intestine. Transcriptome analyses showed that 11,328 of the oligonucleotides demonstrated expression in at least one tissue. Statistical analyses revealed that 1810 genes showed differential expression among tissues (Bonferroni adjusted p < 0.05). Biological pathways identified by DAVID/EASE analysis using a list of 423 tissue-selective genes matched archetypal pathways in the corresponding human or mouse tissue. Real-time quantitative PCR confirmed expression patterns for 9 of 11 genes tested. Our results demonstrate that this first-generation porcine oligonucleotide array is informative and the specificity is high. This is essential validation for investigators using the Qiagen-NRSP8 array for porcine functional genomics and for using the pig in modeling important physiological problems.

Animals↗

PLET1 (C11orf34), a highly expressed and processed novel gene in pig and mouse placenta, is transcribed but poorly spliced in human.

Sequencing of porcine cDNAs identified a novel EST with high frequency in placenta tissue. Full-length PLET1 (placenta-expressed transcript 1, also called C11orf34) matched a mouse cDNA and many bovine and mouse ESTs but no human transcripts or ESTs. However, the porcine cDNA matched several putative exons within a human genomic DNA fragment on chromosome 11. This human locus is in a region of conserved synteny with pig chromosome 9, to which the porcine gene was subsequently mapped. RNA blot hybridization showed that this gene had high expression in porcine and mouse conceptus and throughout placenta development. In situ hybridization using mouse placenta showed PLET1 expression in trophoblast cells of the labyrinth, as well as in spongiotrophoblast and glycogen trophoblast cells. However, no expression of PLET1 was detected by RNA blot analysis of human placenta, although RT-PCR analysis detected very small amounts of partially spliced RNA that were significantly less abundant than the RNA levels in mouse placenta. Donor and acceptor splicing site sequences in the exons of the human gene are poorly conserved and may be the cause of inefficient splicing found specifically in human tissue. Our data correct GenomeScan annotation of this region of the human genome and describe functional gene discovery in mammals not recognized in human EST projects.

Amino Acid Sequence↗

[Isolation, localization and expression of a novel expressed sequence tag from pig skeletal muscular tissue].

A novel expressed sequence tag (ESThp9-1, GenBank accession number: B1596262) was isolated from pig skeletal muscular tissue by using the mRNA differential display technique. BLAST analysis revealed that the 196 bp long EST (ESThp9-1) was not homologous to any of the known porcine genes in the database but similar to rat U3A small nuclear RNA (87% identity over 93 nucleotides) and mouse U3B.4 small nuclear RNA (85% identity over 96 nucleotides). Semi-quantitative reverse transcription polymerase chain reaction indicated that EST9hp-1 was expressed in most of tissue of the pig. ESThp9-1 was physically mapped on sus scrofa chromosome 12q1.1-q1.5 and linked with microsatellite S0090 by using somatic cell hybrid panel and radiation hybrid panel analysis. According to the homologous information and result of physical mapping, ESThp9-1 was presumed to be one member of the porcine U3 gene family.

Animals↗

Genetic relationships among twelve Chinese indigenous goat populations based on microsatellite analysis.

Twelve Chinese indigenous goat populations were genotyped for twenty-six microsatellite markers recommended by the EU Sheep and Goat Biodiversity Project. A total of 452 goats were tested. Seventeen of the 26 microsatellite markers used in this analysis had four or more alleles. The mean expected heterozygosity and the mean observed heterozygosity for the population varied from 0.611 to 0.784 and 0.602 to 0.783 respectively. The mean F ST (0.105) demonstrated that about 89.5% of the total genetic variation was due to the genetic differentiation within each population. A phylogenetic tree based on the Nei (1978) standard genetic distance displayed a remarkable degree of consistency with their different geographical origins and their presumed migration throughout China. The correspondence analysis did not only distinguish population groups, but also confirmed the above results, classifying the important populations contributing to diversity. Additionally, some specific alleles were shown to be important in the construction of the population structure. The study analyzed the recent origins of these populations and contributed to the knowledge and genetic characterization of Chinese indigenous goat populations. In addition, the seventeen microsatellites recommended by the EU Sheep and Goat Biodiversity Project proved to be useful for the biodiversity studies in goat breeds.

Animals↗

Genetic variation and relationships of eighteen Chinese indigenous pig breeds.

Chinese indigenous pig breeds are recognized as an invaluable component of the world's pig genetic resources and are divided traditionally into six types. Twenty-six microsatellite markers recommended by the FAO (Food and Agriculture Organization) and ISAG (International Society of Animal Genetics) were employed to analyze the genetic diversity of 18 Chinese indigenous pig breeds with 1001 individuals representing five types, and three commercial breeds with 184 individuals. The observed heterozygosity, unbiased expected heterozygosity and the observed and effective number of alleles were used to estimate the genetic variation of each indigenous breed. The unbiased expected heterozygosity ranged between 0.700 (Mashen) and 0.876 (Guanling), which implies that there is an abundant genetic variation stored in Chinese indigenous pig breeds. Breed differentiation was shown by fixation indices (FIT, FIS, and FST). The FST per locus varied from 0.019 (S0090) to 0.170 (SW951), and the average FST of all loci was 0.077, which means that most of the genetic variation was kept within breeds and only a little of the genetic variation exists between populations. The Neighbor-Joining tree was constructed based on the Nei DA (1978) distances and one large cluster with all local breeds but the Mashen breed, was obtained. Four smaller sub-clusters were also found, which included two to four breeds each. These results, however, did not completely agree with the traditional type of classification. A Neighbor-Joining dendrogram of individuals was established from the distance of -ln(proportions of shared alleles); 92.14% of the individuals were clustered with their own breeds, which implies that this method is useful for breed demarcation. This extensive research on pig genetic diversity in China indicates that these 18 Chinese indigenous breeds may have one common ancestor, helps us to better understand the relative distinctiveness of pig genetic resources, and will assist in developing a national plan for the conservation and utilization of Chinese indigenous pig breeds.

Alleles↗