A fast, efficient and high-throughput procedure involving laser microdissection and RT droplet digital PCR for tissue-specific expression profiling of rice roots.

BACKGROUND: In rice, the cortex and outer tissues play a key role in submergence tolerance. The cortex differentiates into aerenchyma, which are air-containing cavities that allow the flow of oxygen from shoots to roots, whereas exodermis suberification and sclerenchyma lignification limit oxygen loss from the mature parts of roots by forming a barrier to root oxygen loss (ROL). The genes and their networks involved in the cellular identity and differentiation of these tissues remain poorly understood. Identification and characterization of key regulators of aerenchyma and ROL barrier formation require determination of the specific expression profiles of these tissues. RESULTS: We optimized an approach combining laser microdissection (LM) and droplet digital RT-PCR (ddRT-PCR) for high-throughput identification of tissue-specific expression profiles. The developed protocol enables rapid (within 3 days) extraction of high-quality RNA from root tissues with a low contamination rate. We also demonstrated the possibility of extracting RNAs from paraffin blocks stored at 4 °C without any loss of quality. We included a detailed troubleshooting guide that should allow future users to adapt the proposed protocol to other tissues and/or species. We demonstrated that our protocol, which combines LM with ddRT-PCR, can be used as a complementary tool to in situ hybridization for tissue-specific characterization of gene expression even with a low RNA concentration input. We illustrated the efficiency of the proposed approach by validating three of four potential tissue-specific candidate genes detailed in the RiceXpro database. CONCLUSION: The detailed protocol and the critical steps required to optimize its use for other species will democratize tissue-specific transcriptome approaches combining LM with ddRT-PCR for analyses of plants.

BDNF Val66Met Polymorphism, the Allele-Specific Analysis by qRT-PCR - a Novel Protocol.

Background: Alteration in brain-derived neurotrophic factor (BDNF) production is a marker of neuropathological conditions, which has led to the investigation of Val66Met polymorphism occurring in the human BDNF gene (BDNF). Presently, there are no reported methods available for the analysis of Val66Met impact on human BDNF functioning. Purpose: To develop a qRT-PCR protocol for the allele-specific expression evaluation of the Val66Met polymorphism in BDNF. Methods: Using RNA extracted from muscle samples of 9 healthy volunteers (32.9 ± 10.3 y) at rest and following a maximal effort aerobic capacity exercise test, a protocol was developed for the detection of Val66/Met66 allele-specific BDNF expression in Real-Time Quantitative Reverse Transcription PCR (qRT-PCR) - relative to housekeeping genes - and validated by absolute quantification in Droplet Digital Polymerase Chain Reaction (ddPCR). Results: Differences in the relative values of BDNF mRNA were confirmed by ddPCR analysis. HPRT1 and B2M were the most stable genes expressed in muscle tissue among different metabolic conditions, while GAPDH revealed to be metabolic responsive. Conclusion: Our qRT-PCR protocol successfully determines the allele-specific detection and changes in BDNF expression regarding the Val66Met polymorphism.

Identification of Differentially Expressed Genes of Rice Under Cadmium Stress Using DDRT-PCR Approach.

Cadmium (Cd) is one of the hazardous environmental pollutants, and it can be harmful to human health through consumption of food-plants capable of bioaccumulating Cd. Therefore, lowering cadmium accumulation in plants is highly desirable. Here, a rice cultivar 'Qisanzhan' was studied using differential display reverse transcription-polymerase chain reaction (DDRT-PCR). Fifty-six differentially expressed genes were found in the root tips of 4-leaf stage rice seedlings exposed to 4 and 12 h of 50 µmol/L Cd(NO3)2 in a nutrient solution using DDRT-PCR. Further validation using semi-quantitative RT-PCR showed that the expression patterns of 16 genes were consistent with those found in DDRT-PCR. These genes encode receptor-like protein kinase, pleiotropic drug resistance protein, aquaporin protein, plasma membrane ATPase, etc. The differentially genes identified here can be used to obtain a better understanding of the molecular mechanisms of Cd absorption and accumulation in plants.

Differentially expressed genes in response to cyadox in swine liver analyzed by DDRT-PCR.

Cyadox is a good antimicrobial growth-promoter of quinoxalines. However, the molecular mechanism of action remains unclear. A growth performance study and mRNA differential display reverse transcription polymerase chain reaction (DDRT-PCR) in combination with Northern dot-blot and reverse Northern dot-blot analysis were conducted to determine the differentially expressed genes in liver tissues of piglets after treatment with cyadox. Transcription levels of the differentially expressed genes were quantificated by realtime RT-PCR in porcine primary hepotocytes. Cyadox could significantly promote body weight of piglets via feed with average daily gain (ADG) improved by 24.7% and 64.8% in 100 and 500mg/kg group, compared with control. A total of eight differentially expressed genes were found, of which the expression levels of five genes had positive correlation with cyadox dose. One gene expression had a negative correlation with cyadox dose and it was a new gene. The other two genes were up-regulated by cyadox, but the expression quantity was invariably when the cyadox doses were increased. Among the up-regulated genes, one was transcriptional regulating factor, two were growth-related factors, one was involved in immune defense and immune-regulation and three might be involved in the maintenance of normal development. In primary cultured pig hepatocytes, cyadox treatment evoked a significant time-dependent effect of eight genes expression. The results suggest, at the transcriptional level in vitro and in vivo, that growth factor and metabolism may be associated with cyadox growth-promoting activity, whereas immune defense and immune-regulation could play major roles in prophylaxis of cyadox in piglets.

Differential Gene Expression of Longan Under Simulated Acid Rain Stress.

Differential gene expression profile was studied in Dimocarpus longan Lour. in response to treatments of simulated acid rain with pH 2.5, 3.5, and a control (pH 5.6) using differential display reverse transcription polymerase chain reaction (DDRT-PCR). Results showed that mRNA differential display conditions were optimized to find an expressed sequence tag (EST) related with acid rain stress. The potential encoding products had 80% similarity with a transcription initiation factor IIF of Gossypium raimondii and 81% similarity with a protein product of Theobroma cacao. This fragment is the transcription factor activated by second messenger substances in longan leaves after signal perception of acid rain.

Cloning and transcriptional expression of a novel gene during sex inversion of the rice field eel (Monopterus albus).

We performed annealing control primer (ACP)-based differential-display reverse transcription-polymerase chain reaction (DDRT-PCR) to isolate differentially expressed genes (DEGs) from the stage IV ovary and ovotestis of the rice field eel, Monopterus albus. Using 20 arbitrary ACP primers, 14 DEG expressed-sequence tags were identified and sequenced. The transcriptional expression of one DEG, G2, was significantly greater in the ovotestis than the stage IV ovary. To understand the role of G2 in sex inversion, G2 cDNA was cloned and semi-RT-PCR, real time PCR were performed during gonad development. The full-length G2 cDNA was 650 base pairs (bp) and it comprised a 5'-untranslated region (UTR) of 82 bp, a 3'-UTR of 121 bp and an open reading frame of 444 bp that encoded a 148-amino acid protein. The expression of G2 was weak during early ovarian development until the stage IV ovary, but expression increased significantly with gonad development. We speculate that G2 may play an important function during sex inversion and testis development in the rice field eel, but the full details of the function of this gene requires further research.

Evaluation of Parkia pendula lectin mRNA differentially expressed in seedlings / Avaliação de mRNA da lectina de Parkia pendula diferencialmente expressa em plântulas

Parkia pendula (Willd.) Walp. (Fabaceae) is a neotropical species of the genus Parkia more abundantly distributed in Central to South America. From the seeds of P. pendula a glucose/mannose specific lectin (PpeL) was isolated that has been characterised and used as a biotechnological tool but until now this is the first manuscript to analyse P. pendula mRNA expression in seedlings. For this porpoise a Differential display reverse transcription polimerase chain reaction (DDRT-PCR) was used to evaluate the expression of P. pendula lectin mRNAs in non-rooted seedlings. No bands were observed in the agarose gel, indicating the absence of mRNA of PpeL seedlings. our findings confirm that lectins mRNAs are differently regulated among species even if they are grouped in the same class.

Parkia pendula (Willd.) Walp. (Fabaceae) é a espécie neotropical do gênero Parkia mais abundantemente distribuída na América Central a do Sul. Das sementes de P. pendula foi isolada uma lectina glicose/manose específica (Ppel) que foi caracterizada e usada como ferramenta biotecnológica, porém até o momento esse é o primeiro artigo a analisar a expressão do mRNA nas plântulas de P. pendula. Para esse propósito uma reação de PCR diferencial de transcriptase reversa (DDRT-PCR) foi utilizada para avaliar a expressão do mRNA da lectina de P. pendula em plântulas não enraizadas. Nenhuma banda foi observada no gel de agarose, indicando a ausência de mRNA das plântulas de PpeL. Nossos achados confirmam que os mRNAs de lectinas são regulados de forma diferentes entre as espécies, mesmo que sejam agrupadas na mesma classe.

Candidate Genes Expressed in Tolerant Common Wheat With Resistant to English Grain Aphid.

The English grain aphid, Sitobion avenae (F.) (Hemiptera: Aphididae), is a common worldwide pest of wheat (Triticum aestivum L.). The use of improved resistant cultivars by the farmers is the most effective and environmentally friendly method to control this aphid in the field. The winter wheat genotypes 98-10-35 and Amigo are resistant to S. avenae. To identify genes responsible for resistance to S. avenae in these genotypes, differential-display reverse transcription-polymerase chain reaction was used to identify the corresponding differentially expressed sequences in current study. Two backcross progenies were obtained by crossing the two resistant genotypes with the susceptible genotype 1376. Six potential expected-differential bands were sequenced. Lengths of the expressed sequence tags ranged from 128 to 532 bp. Although these expressed sequences were likely associated with S. avenae resistance, there was one expressed sequence tag located on 7DL chromosome, and its potential function may associate with the ability to maintain photosynthesis in wheat. That serves as an active way for tolerant common wheat with resistant to S. avenae. Cloning the full length of these sequences would help us thoroughly understand the mechanism of wheat resistance to S. avenae and be valuable for breeding cultivars with S. avenae resistance.

Primarily screening and analyzing ESTs differentially expressed in rats' primary liver cancer.

OBJECTIVE: To screen and analyze key express sequence tags (ESTs) which were differentially displayed in every period of SD rats' primary hepatic carcinoma and reveal the molecular mechanism of carcinogenesis. METHODS: Using diethylnitrosamine (DENA) as a cancerigenic agent, animal models with different phases of primary hepatic cancer were constructed in SD rats. Rats were respectively sacrificed at d 14, d 28, d 56, d 77, d 105 and d 112 after the rats received DENA by gavage, then the livers were harvested. One part of the livers was classified according to their pathological changes, while the other was reserved for molecular mechanism studies on hepatocarcinogenesis. The differentially expressed genes were isolated from both normal and morbid tissues by mRNA differential display technique (DDRT-PCR). After the fragments were sequenced, bioinformatics were used to analyze the results. RESULTS: Twelve differentially expressed cDNA fragments were obtained. Nine fragments had the homology with known cDNA clones, especially EST-7 was similar to BN/SsNHsdMCW mitochondrion gene and the identity was 100% which suggested EST-7 may be the part of BN/SsNHsdMCW mitochondrion gene. In contrast, other three fragments (EST-1, EST-3 and EST-5) had extremely low identity to any genes registered in GENBANK databases. CONCLUSIONS: BN/SsNHsdMCW mitochondrion gene was expressed in different periods of hepatocarcinogenesis. Moreover, EST-1, EST-3 and EST-5 were suggested to contribute to the development of rat hepatocarcinogenesis, and thus may be candidates of new targets of oncogenes or cancer suppressor genes.

Exequibility of differential gene expression analysis by DDRT-PCR in murine bone marrow cells / Exequibilidade do DDRT-PCR para análise da expressão gênica diferencial em células de medula óssea murina

Model of study: Experimental study. Introduction: Recently, stem cell research has generated great interest due to its applicability in regenerative medicine. Bone marrow is considered the most important source of adult stem cells and the establishment of new methods towards gene expression analysis regarding stem cells has become necessary. Thus Differential Display Reverse Transcription Polymerase Chain Reaction (DDRT-PCR) may be an accessible tool to investigate small differences in the gene expression of different stem cells in distinct situations. Aim: In the present study, we investigated the exequibility of DDRT-PCR to identify differences in global gene expression of mice bone marrow cells under two conditions. Methods: First, bone marrow cells were isolated fresh and a part was cultivated during one week without medium replacement. Afterwards, both bone marrow cells (fresh and cultivated) were submitted to gene expression analyses by DDRT-PCR...

Modelo do estudo: Estudo Experimental. Introdução: Atualmente a pesquisa com células-tronco tem gerado grande interesse devido a sua aplicabilidade no campo na medicina regenerativa. A medula óssea é considerada a maior fonte de células-tronco adultas e o estabelecimento de novos métodos para a análise da expressão gênica torna-se estritamente necessário. Desse modo, o "Differential Display Reverse Transcription Polymerase Chain Reaction (DDRT-PCR)", pode ser uma ferramenta acessível para investigação de pequenas diferenças no nível de expressão gênica em diferentes tipos celulares, sob distintas condições. Objetivo: Neste presente trabalho nós investigamos a exequibilidade do DDRT-PCR na identificação de diferenças no nível de expressão gênica global em células da medula óssea de camundongos sob duas condições. Métodos: Primeiramente, a medula óssea foi isolada frescamente e uma secunda parte foi cultivada por uma semana sem troca de meio. Posteriormente, as células da medula (fresca e cultivada) foram submetidas a análise da expressão gênica, seguindo a metodologia de DDRT-PCR...

Isolation and characterization of ripening related pectin methylesterase inhibitor gene from banana fruit.

Identification of ethylene-regulated and ripening-related genes from banana (Musa acuminata Var. Harichaal) fruits using DDRT-PCR led to the isolation of differentially expressed partial cDNA of pectin methylesterase inhibitor (MaPMEI) gene. Its full-length cDNA sequence consisted of a 567 bp ORF, encoding a protein of 189 aa with deduced molecular mass 19.6 kDa. Expression pattern of MaPMEI gene revealed that upon ethylene treatment, this gene is up-regulated initially giving maximum expression in post-climacteric stage then decreases slightly in later stages of ripening. 1-MCP, a known ethylene perception inhibitor, inhibits both fruit ripening as well as the transcript level of this gene. Also, the transcripts of MaPMEI gene were not detected during the short time ethylene treatment suggesting this gene appears to be not directly induced by ethylene. Interestingly, MaPMEI gene showed fruit specific expression that indicates its possible role in the regulations of PMEs in fruits. In silico analysis revealed a predicted signal peptide sequence necessary for localization of MaPMEI in the cell wall. Furthermore, the four Cys residues involved in disulfide bridges are conserved in MaPMEI similar to other PMEIs and invertase inhibitors. Phylogenetic analysis further suggests that the MaPMEI identified in this study is more closely related to PMEIs than to invertase inhibitors.

Analysis of Gene Expression in Primary Hepatocellular Carcinoma Using Differentially Displayed Reverse Transcriptase Polymerase Chain Reaction / 대한소화기학회지

BACKGROUND/AIMS: The investigation of a specific tumor marker for hepatocellular carcinoma (HCC) is needed to examine the carcinogenesis and to select the patients for treatment options. The aim of this study was to find the genes related to HCC. We also examined the expression level of these genes in cancer cell lines and tissue specimens. METHODS: Three pairs of HCC tissue and non-neoplastic hepatic tissue around the HCC were collected from three patients who underwent resection for HCC. Differential display reverse transcriptase-PCR (DD RT-PCR) using GeneFishing (TM) PCR was used to detect the differences in the gene expression between in HCC tissue and non-neoplatic tissue. Up- or down-regulated genes in HCC tissue were identified through BLAST searches after cloning and sequencing assays. Real-time RT-PCR assay was employed to detect the expression rate in 11 HCC tissues and human cancer cell lines. RESULTS: Differentially expressed 21 genes were identified, and they were classified as genes involved in protein metabolism, ubiquitin-dependent protein catabolism, carbohydrate metabolism, lipid metabolism, DNA repair, and inflammatory response. CONCLUSIONS: We identified differentially expressed genes in HCC, and these genes may play an important role in the study of hepatocarcinogenesis, development of biomarker, and target therapy for HCC.

Identification of differentially expressed cDNAs in Acanthamoeba culbertsoni after mouse brain passage

Free-living amoebae of the genus Acanthamoeba are causative agents of granulomatous amebic encephalitis and amebic keratitis. Because the virulence of Acanthamoeba culbertsoni cultured in the laboratory is restored by consecutive brain passages, we examined the genes induced in mouse brain-passaged A. culbertsoni by differential display reverse transcriptase polymerase chain reaction (DDRT-PCR). Enhanced A. culbertsoni virulence was observed during the second mouse brain passage, i.e., infected mouse mortality increased from 5% to 70%. Ten cDNAs induced during mouse brain passage were identified by DDRT-PCR and this was confirmed by northern blot analysis. BlastX searches of these cDNAs indicated the upregulations of genes encoding predictive NADH-dehydrogenase, proteasomal ATPase, and GDP-mannose pyrophosphorylase B, which have previously been reported to be associated with A. culbertsoni virulence factors.

Identification of Gene Expression and Gene Ontology Classification by Differential Display RT-PCR in Human Cervical Squamous Cell Carcinoma / 대한산부인과학회잡지

OBJECTIVE: The molecular pathology of cervical cancer associated with human papillomavirus infection is presently unclear. In an effort to clarify the multiple interactions of a number of genes involved in cervical carcinogenesis, the gene expression profiles and pathogenic cellular processes between human cervical squamous cell carcinoma and normal cervix were investigated by mRNA differential display and the Gene Ontology analysis. METHODS: Cervical cancer biopsies were obtained from patients at the Department of Obstetrics and Gynecology, The Catholic University of Korea. The disease status was assigned according to the International Federation of Gynecology and Obstetrics. The squamous cell carcinoma tissue samples of 3 patients invasive cancer stage II (1), IV (2) were investigated by mRNA differential display. As a control, we used a common reference that was mixed with equal amount of RNA obtained from 17 normal cervix to obtain variation- independent control. Also, we constructed hierarchical functional structures using gene ontology. Then, the specific function groups were correlated with differential gene expression profiles. In addition, specific gene expression patterns in several tissue samples were investigated by using DDRT-PCR analysis. RESULTS: Differentially expressed 191 genes were identified in tumor samples. Of these genes, 128 were up-regulated and 63 were down-regulated above 1.5-fold. The gene expression profiles were classified into 46 mutually dependent function sets and organized into sub-function sets depending on the cervical cancer pathway, suggesting the potentially significant genes of unknown function affected by carcinogenesis pathway. The genes related to metabolism, signal transduction, and chaperon activity were significantly up-regulated. In contrast, significant down-regulations were shown in nucleic acid binding activity, tumor suppressor and structural activity. Reliable gene expression data shows the validation of profiling method for studying the cervical cancer-specific pathway. CONCLUSION: The specific functions assigned to each expressed gene were correlated with gene ontology for the establishment of a powerful cervical carcinogenesis pathway. The results suggest that the differentially regulated cellular process profiles have an important impact on discovery of pathogenic pathway in human cervical squamous cell carcinoma and provide the potentially significant genes of unknown function. Also, the gene ontology analysis can overcome the complexity of the expression profiles of mRNA differential display via a cellular process level approach. Thereby, a valuable prognostic candidate gene with real relevance to disease-specific pathogenesis can be found at the cellular process levels.

Search for Genes Potentially Related to Germ Tube Formation in Candida albicans by Differential-Display Reverse Transcription Polymerase Chain Reaction

Candida albicans exhibits the ability to grow in either a yeast or a mycelia form in response to different environmental factors. The mycelia form, found in infected tissues, is important as a virulence factor in the adherence of the organism to the host epithelium. In vitro, the morphological transition can be induced by environmental shifts in the growing conditions, or by a variety of exogenous factors, including ambient pH, nutritional status and temperature. The differential-display reverse transcription polymerase chain reaction (DDRT-PCR) is a powerful technique for comparing gene expression between cell types, stages of development or differentiation. Hyphae related genes were identified and characterized using a PCR-based differential display. Candida albicans formed a germ tube when cultured in rabbit serum, RPMI 1640 medium or 39degrees C-YPD medium. We gained 21 cDNA bands showing a different expression pattern from that of the uninduced culture. DNA was extracted from the same location of the isolated bands, and PCR was performed under the same conditions, which reamplified the PCR product, showing the specific expression patterns according to the culture conditions. We cloned 18 germ tube-related cDNA clones (inserts average size is 80 - 700 bp) and sequenced them. The nucleotide sequences of the 18 clones were identified through in the present study from GenBank, and were found to have the accession number (AF405213-AF405230). We could not find any nucleotide sequence having a high homology with these clones. This study could form a part of the projects in the search for genes related to the germ tube formation of C. albicans.

Characterization of the Two Genes Differentially Expressed During Development in Human Fetal Astrocytes

Astrocytes are ubiquitous in the brain and have multiple functions. It is becoming clear that they play an important role in monitoring the neuromicroenvironment, information processing, and signaling in the central nervous system (CNS) in normal conditions and that they respond to CNS injuries. During the development of the CNS, astrocytes play a key role as a substrate for neuronal migration and axonal growth. To identify genes that could participate in astrocyte maturation, we used the differential display reverse transcription-PCR (DDRT-PCR) method. Human fetal astrocytes were cultured and total RNAs were isolated at intervals of 5 days for 50 days. Using 24 primer combinations, we identified a set of 18 candidate cDNAs deriving from the excised DDRT-PCR bands. DNA sequencing revealed 16 genes that have been described already. We found that RTP, TG, hTM-alpha, SPARC, TRIP7, and RPL7 genes were expressed increasingly, while HMGCR, RPL27a, NACA, NPM, and TARBP2 genes were expressed decreasingly, according to their culture stages. We also found two unidentified genes, A3 and C8, which were expressed differently in culture stages; the former was expressed decreasingly and the latter increasingly. These two genes were found in the same amount in genomic DNA from various human cells such as astrocytes, astrocytoma, trophoblasts and lymphocytes. The A3 gene was found only in human genomic DNA, but not in rat (ATr5), mouse (RAW264.7), or monkey (Vero) cells, whereas the C8 gene was found in human genomic DNA and monkey cells, but not in rat or mouse cells. We analysed these two genes for identification. There was > 92% nucleotide sequence identity between the A3 gene (3, 626 bp) and the Homo sapiens general transcription factor 3 (GTF3), and > 96% nucleotide sequence identity between the C8 gene (2, 401 bp) and the transmembrane receptor Unc5h2. These findings suggest that these two genes may participate in some functional roles within the cells.

From Library Screening to Microarray Technology: Strategies to Determine Gene Expression Profiles and to Identify Differentially Regulated Genes in Plants.

Hybridization to DNA microarrays and high density membrane filters, serial analysis of gene expression (SAGE), the cDNA-AFLP technique, restriction fragment-coupled differential display (RC4D), differential display reverse transcription PCR (DDRT-PCR) and also the differential screening of standard and subtracted cDNA libraries are techniques being used extensively to determine transcription patterns or to identify differentially regulated genes in plants and other organisms. In this review, commonly used display systems are evaluated and compared. The general principles on which the different techniques are based and which determine their potential and their limitations are described. Performance aspects of each method are discussed, and existing applications of each method are briefly surveyed. Some typical examples are considered to illustrate how differential display systems have been applied to plants and to what extent these techniques have contributed to our understanding of plant gene expression.

Several Genes Expressed During Morphogenesis of Lentinus edodes (ImHyup-1)

Differential display of reverse transcription (DDRT)-PCR was conducted to have a profile of the differentially expressed genes during the formation of fruiting body of Lentinus edodes. The lines of L. edodes (ImHyup-1) employed were cultivated in the artificial blocks of sawdust, and the fruiting body was induced from the mycelia or the mass protruded from the brown surface of the sawdust blocks. RNAs were prepared from the four different developmental stages; mycelial, primordial, and stipes and pileus of fruiting body. The fragments of cDNA were synthesized from the combinations of the arbitrary primers and 3' one anchored Oligo-dT primer. Twelve combinations using the primers have been tested, and among them nineteen bands were identified as differentially expressed. Those genes were further analyzed by DNA sequencing and followed by homology search. Characterization of one clone was conducted as a preliminary data and more are under investigation.

The alteration of gene expression in cortex tissue following BALB/c rat aging / 中华老年医学杂志

Objective To identify and clone rat aging-related genes to provide clues for human aging mechanism. Methods Improved different display reverse transcript-PCR method was applied to identify differentially expressed genes in cortex tissues of 4-month and 24-month old BALB/c mouse. Results Forty-two cDNA fragments with differential expression were identified, and 21 with increase and 21 with decrease of expression in old mice. Among them, 17 represented genes with known protein function, 12 represented known gene sequences but their protein function was unknown, and the other 13 probably belonged to new cDNAs. Among the genes with known protein function, 2 genes were associated with oxidative stress, 3 with energy production, and 4 with protein metabolism, respectively. Additionally, gene expression alterations were also found in those related to cell apoptosis, neurodegenerative disorder, and growth and development regulation. Conclusions Rat aging might be related with the alteration of oxidative stress status, energy production and protein metabolism.

Cloning aged-related gene of mouse thymus / 中国免疫学杂志

Objective:Differential expression analysis and cloning aged related genes of mouse thymus Methods:Different expressions of thymus mRNAs from 1 and 10 month old mouse were analyzed by DDRT PCR and different expression sequence tags (ESTs) were obtained One EST that represented high expressed level in one month mouse thymus was probed to screen mouse thymus cDNA library One 827 bp cDNA fragment was obtained and was extended to 1 406 bp by PCR Results:Homology analysis showed that mt22 1406 contained one 438AA coding region and showed high similarity with human elongation factor1?(EF1?) The Genbank accession number is BE241062 Conclusion:Cloning one gene related with mouse thymus aging