Dataset Information

Large-scale temporal gene expression profiling during gonadal differentiation and early gametogenesis in rainbow-trout

ABSTRACT: Animals and samplings: Research involving animal experimentation has been approved by the author's institution (authorization number 35-14) and conforms to NIH guidelines. All-male and all-female rainbow trout populations were obtained from the INRA experimental fish farm (Drennec, France) using breeders from the Mirwart strain. At 55 days post-fertilization (55 dpf, i.e., the onset of the free swimming), a male and female batch of 1500 fry each were transferred in 0.3 m3 tanks with recirculating water conditions. They were held at 12°C under constant photoperiod (12h light : 12h dark) and fed ad libitum with a commercial diet (dry pellet food, BiomarTM, Brande, Denmark). In each group, from 20 to 100 gonads, depending on the age of the fish, were sampled and pooled in duplicates at various stages of development : the onset of the free swimming period after complete yolk resumption (Day 0 = D0), D7, D12 (around the first occurrence of oocyte meiosis), D27 (first ovarian lamellar structures), D60 (first previtellogenic oocytes), D90 and D110. There were immediately frozen in liquid nitrogen and stored at -80°C until RNA extraction. Additional gonads were sampled at the same dates for histological analysis performed as previously described. Total RNA extraction and Reverse Transcription: Total RNA was extracted using TRIzol reagent (Invitrogen, Cergy Pontoise, France). Total RNA concentration was determined with an Agilent 2100 Bioanalyzer and the RNA 6000 LabChip kit (Agilent Technologies, Stockport, UK) according to the manufacturer's instructions. For cDNA synthesis, 1µg of RNA was denaturated in the presence of random hexamers (0.5µg) for 5 min at 70°C, and then chilled on ice. Reverse transcription (RT) was performed at 37°C for 1 h using M-MLV reverse transcriptase (Promega, Madison, WI) as described by the manufacturer. Primers design: Trout candidate gene homologues were searched in international public databanks using a reciprocal blast hit strategy. Candidate genes were chosen according to a bibliographic analysis showing their direct or indirect involvement in the sex differentiation cascade in vertebrates. All the primers were purchased from Eurogentec (Eurogentec, Seraing, Belgium). These primers were manually designed respecting whenever possible the following restriction parameters : 21-23 bp length, no more than 4 identical successive nucleotides, 30-70% GC content, a maximum of 2 G or C among the five 3'-end bases, no primer dimers and a short amplicon size (70-150 bp). Secondary structures were searched with DNA mfold (http://bioinfo.math.rpi.edu/~mfold/DNA/form1.cgi). Whenever possible, each pair was chosen with at least one primer flanking an intron-exon boundary, in order to prevent genomic amplification. Real-time RT-PCR Real-time RT-PCR was carried out on an iCycler iQTM (BioRad, Hercules, CA). Reactions were performed in 20µl with 300nM of each primer, 5µl of a 1/50 dilution of the RT reaction and the SYBER-Green PCR master Mix (Eurogentec) according to the manufacturer's instructions. After two incubation steps (50°C 10 min, 95°C 2 min), the thermal cycling protocol was 95°C for 10 min followed by 40 cycles of PCR (95°C 30 s, 60°C or 65°C 1 min). For each primer set the efficiency of the PCR reaction (linear equation : y = slope + intercept) was measured in triplicate on serial dilutions of the same cDNA sample (pool of reverse transcribed RNA samples). Real-time PCR efficiencies for each reaction were then calculated using the formula : Efficiency (E)=[10(1/slope)]-1. Melting curve analysis was also performed for each gene to check the specificity and identity of the RT-PCR products. The relative amount of the target RNA called the Starting Quantity (SQ) was then determined using the I-Cycler IQ software by comparison with the corresponding standard curve for each sample run in duplicate. SQ were calculated as follow : SQ = [10((Ct -intercept)/slope))]-1 where Ct is the Cycle threshold of the unknown sample. Each transcript level was then normalized by division with the expression values of the constitutive elongation factor 1 alpha (EF1a) used as an internal standard. Keywords: ordered

ORGANISM(S): Oncorhynchus mykiss

PROVIDER: GSE2151 | GEO | 2005/06/01

SECONDARY ACCESSION(S): PRJNA91411

REPOSITORIES: GEO

ACCESS DATA

Dataset's files

Source:

			Action	DRS
		Other

Items per page:

1 - 1 of 1

Similar Datasets

Project description:Animals and samplings: Research involving animal experimentation has been approved by the author's institution (authorization number 35-14) and conforms to NIH guidelines. All-male and all-female rainbow trout populations were obtained from the INRA experimental fish farm (Drennec, France) using breeders from the Mirwart strain. At 55 days post-fertilization (55 dpf, i.e., the onset of the free swimming), a male and female batch of 1500 fry each were transferred in 0.3 m3 tanks with recirculating water conditions. They were held at 12°C under constant photoperiod (12h light : 12h dark) and fed ad libitum with a commercial diet (dry pellet food, BiomarTM, Brande, Denmark). In each group, from 20 to 100 gonads, depending on the age of the fish, were sampled and pooled in duplicates at various stages of development : the onset of the free swimming period after complete yolk resumption (Day 0 = D0), D7, D12 (around the first occurrence of oocyte meiosis), D27 (first ovarian lamellar structures), D60 (first previtellogenic oocytes), D90 and D110. There were immediately frozen in liquid nitrogen and stored at -80°C until RNA extraction. Additional gonads were sampled at the same dates for histological analysis performed as previously described. Total RNA extraction and Reverse Transcription: Total RNA was extracted using TRIzol reagent (Invitrogen, Cergy Pontoise, France). Total RNA concentration was determined with an Agilent 2100 Bioanalyzer and the RNA 6000 LabChip kit (Agilent Technologies, Stockport, UK) according to the manufacturer's instructions. For cDNA synthesis, 1µg of RNA was denaturated in the presence of random hexamers (0.5µg) for 5 min at 70°C, and then chilled on ice. Reverse transcription (RT) was performed at 37°C for 1 h using M-MLV reverse transcriptase (Promega, Madison, WI) as described by the manufacturer. Primers design: Trout candidate gene homologues were searched in international public databanks using a reciprocal blast hit strategy. Candidate genes were chosen according to a bibliographic analysis showing their direct or indirect involvement in the sex differentiation cascade in vertebrates. All the primers were purchased from Eurogentec (Eurogentec, Seraing, Belgium). These primers were manually designed respecting whenever possible the following restriction parameters : 21-23 bp length, no more than 4 identical successive nucleotides, 30-70% GC content, a maximum of 2 G or C among the five 3'-end bases, no primer dimers and a short amplicon size (70-150 bp). Secondary structures were searched with DNA mfold (http://bioinfo.math.rpi.edu/~mfold/DNA/form1.cgi). Whenever possible, each pair was chosen with at least one primer flanking an intron-exon boundary, in order to prevent genomic amplification. Real-time RT-PCR Real-time RT-PCR was carried out on an iCycler iQTM (BioRad, Hercules, CA). Reactions were performed in 20µl with 300nM of each primer, 5µl of a 1/50 dilution of the RT reaction and the SYBER-Green PCR master Mix (Eurogentec) according to the manufacturer's instructions. After two incubation steps (50°C 10 min, 95°C 2 min), the thermal cycling protocol was 95°C for 10 min followed by 40 cycles of PCR (95°C 30 s, 60°C or 65°C 1 min). For each primer set the efficiency of the PCR reaction (linear equation : y = slope + intercept) was measured in triplicate on serial dilutions of the same cDNA sample (pool of reverse transcribed RNA samples). Real-time PCR efficiencies for each reaction were then calculated using the formula : Efficiency (E)=[10(1/slope)]-1. Melting curve analysis was also performed for each gene to check the specificity and identity of the RT-PCR products. The relative amount of the target RNA called the Starting Quantity (SQ) was then determined using the I-Cycler IQ software by comparison with the corresponding standard curve for each sample run in duplicate. SQ were calculated as follow : SQ = [10((Ct -intercept)/slope))]-1 where Ct is the Cycle threshold of the unknown sample. Each transcript level was then normalized by division with the expression values of the constitutive elongation factor 1 alpha (EF1a) used as an internal standard.

Project description:To investigate the regulatory mechanisms governing the malignant signature of different gliomas we analyzed microRNA expression profiles in human tumor samples of world health organization (WHO) grade I (benign tumors), II (low grade tumors) and IV (high grade tumors) and from primary cultures obtained from tumor samples of grade II and IV. Patients This study included tumor samples histologically verified as astrocytic gliomas obtained from patients who had undergone craniotomy for microsurgical tumor removal. According to the revised WHO classification, tumors were diagnosed as: grade I or pilocytic astrocytomas; grade II or diffuse fibrillary astrocytomas; grade IV or glioblastoma multiforme. Primary cell cultures from grade II and grade IV gliomas were also obtained and miRNA expression in these cultures were analyzed RNA extraction Total RNA, including small RNA, was isolated from tissue samples using the mirVanaTM miRNA Isolation Kit (Ambion) following the standard protocol. The quantity and quality of the purified RNA was evaluated by spectrophotometric analysis and electrophoresis on denaturing gel of acrylamide. Multiplex Real-Time Quantitative Reverse-Transcriptase Polymerase Chain Reaction (RT-PCR) The miRNAs were first converted to cDNA using Multiplex RT for TaqMan Array Human MicroRNA Panel. The RT Master mix included 100 mM each of dNTPs , 50 U/ml MultiScrabe reverse transcriptase (Applied Biosystems), 20 U/µl RNase inhibitor (Applied Biosystems) and 10X RT Buffer. The 10 µl reactions, including 7 µl of RT master mix, 2 µl of purified microRNA and 1 µl of Multiplex RT Human primer pool (Applied Biosystem), were incubated in ice for 5 min and then in a thermal cycler for 30 min at 16°C, 30 min at 42°C, 5 min at 85°C, and then hold at 4°C. miRNA levels were normalized to the expression of small nucleolar RNAs, RNU44, RNU48 and RNU6B. All reverse transcriptase reactions, including no-template controls and RT controls, were run in duplicate. Real-time PCR was performed using a standard TaqMan PCR kit procedure on an “Real Time Fast 7900 HT” PCR System (Applied Biosystems). The 100 µl PCR included 50 µl RT product (before diluited 1:60) and 50 µl TaqMan Universal PCR Master Mix (2X) (Applied Biosystems). The total volume were loaded into Card TaqMan Low Density Array Human MicroRNA Panel (Applied Biosystem) including a total of 384 human microRNAs publicated on databases www.sanger.ac.uk. The reaction cards was runned at 50°C for 2 min and 95°C for 10 min, followed by 40 cycles of 97°C for 30s and 59,7°C for 1 min. All reactions were run in triplicate. Analysis of data was performed using the SDS 2.3 software using the 2-∆∆Ct (relative quantitative) method . The ∆Ct of every miRNA was determined in relation to the endogenous control RNA U6 that was invariably expressed in all samples. The ∆∆Ct value was determined in relation to the calibrator, namely the normal brain tissue. Resulting data were grouped according to the tumor grading e selectioned using a cut-off value of 3. Results were expressed as “fold change” over normal brain tissue.

Project description:MicroPoly(A)Pure kits (Ambion) were used to prepare mRNA from P. salmonis-infected and control Atlantic salmon head kidney. Head kidney mRNA samples were prepared from pooled (n = 10) infected or control kidney. Approximately 200 ng of infected or control head kidney mRNA was used as template in aRNA synthesis reactions. Two infected head kidney samples were pooled to yield 8.9 ug of aRNA, and a single control head kidney sample contained 8.4 ug of aRNA. Infected and control head kidney aRNA samples were visualized on agarose gels to check quality and quantity (data not shown). Except for the amounts of aRNA and reverse transcription (RT) primer used, head kidney target labeling reactions and microarray hybridizations were identical. Head kidney target syntheses used 2 ug of aRNA and 2 ug of random primers (Roche). RT primers were mixed with aRNA samples, and nuclease-free H2O (Invitrogen) was added to make 10 ul total volume. Samples were incubated at 70 degrees C for 4 min, then placed on ice. RT reactions included 50 mM Tris HCl pH 8.3, 75 mM KCl, 3 mM MgCl2, 10 mM DTT, 0.5 mM each dATP, dCTP, and dGTP, 0.2 mM dTTP, 0.05 mM Cy3-dUTP or Cy5-dUTP (Amersham), 40U RNAguard ribonuclease inhibitor (Amersham), and 400U Superscript II Rnase H- reverse transcriptase (Invitrogen). RT reactions were incubated at 42 degrees C for 2.5 h, followed by addition of 0.025U RNase A (Sigma) and 1.5U RNase H (New England BioLabs) and incubation at 37 degrees C for 30 min. Labeled targets were cleaned using the Qiaquick PCR purification kit (Qiagen) and precipitated, with 300 mM sodium acetate, 1 ul of 20 ug/ul glycogen (Invitrogen), and 2.5 volumes of 100% ethanol, at -20 degrees C overnight. Each labeled target was recovered by centrifugation (14,000 rpm, 4 degrees C, 1 h), washed in 70% ethanol, air-dried, and resuspended in 60 ul of hybridization buffer: 50% deionized formamide, 5X SSC, 0.1% SDS, 5 ul of 5 ug/ul oligo dT (5’T18[Q-N]3’), 5 ul of 2 ug/ul BSA (Pierce), and 2 ul of 10 ug/ul sonicated human placental DNA (Sigma). Targets were incubated at 96 degrees C for 3 min, and then at 65 degrees C until applied to microarrays. Microarrays were prepared for hybridization by washing 2 X 5 min in 0.1% SDS, washing 5 X 1 min in MilliQ H2O, immersing 3 min in 95 degrees C MilliQ H2O, and drying by centrifugation (2000 rpm, 5 min, in 50 ml conical tube). Microarray hybridizations were run in the dark under HybriSlips hybridization covers (Grace Biolabs) in slide hybridization chambers (Corning) submerged in a 45 degrees C water bath for 16 h. Coverslips were floated off in 45 degrees C (1X SSC, 0.2% SDS), and arrays were washed 1 X 10 min in 45 degrees C (1X SSC, 0.2% SDS), 3 X 4 min in room temperature (0.1X SSC, 0.1% SDS), and 4 X 4 min in room temperature 0.1X SSC. Slides were dried by centrifugation as before. Fluorescent images of hybridized arrays were acquired immediately at 10 um resolution using ScanArray Express (PerkinElmer). The Cy3 and Cy5 cyanine fluors were excited at 543 nm and 633 nm respectively, and the same laser power (90%) and photomultiplier tube (PMT) settings were used for all slides in a study (PMT 75 Cy3, PMT 63 or 64 Cy5 for head kidney study). Fluorescent intensity data were extracted from TIF images using Imagene 5.5 software (Biodiscovery). Keywords: other

Dataset Information

Large-scale temporal gene expression profiling during gonadal differentiation and early gametogenesis in rainbow-trout

Dataset's files

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets