Here, the DNA-RNA hybrids synthesized in Stage 1 are converted into full-length double-stranded cDNAs. The primers for synthesis of second-strand cDNA are created by RNase H, which introduces nicks into the RNA moiety of the cDNA-mRNA hybrids. E. coli DNA polymerase I extends the newly created 3'-hydroxyl termini, using the first-strand cDNA as a template. - [Read Construction of cDNA Libraries Protocol]
Method uses PCR to amplify and display many cDNAs derived from the mRNAs of a given cell or tissue type. The method relies on two different types of synthetic oligonucleotides: anchored antisense primers and arbitrary sense primers. A typical anchored primer is complementary to approx. 13 nucleotides of the poly(A) tail of mRNA and the adjacent two nucleotides of the transcribed sequence. - [Read Differential Display-PCR Protocol]
The goal of this method is to identify transcriptionally active genes in cloned segments of genomic DNA. The protocol uses hybridization and affinity purification to recover biotin-labeled cDNAs that bind to a 500-kb segment of human DNA cloned in a BAC vector. However, the method can be easily adapted to other clones of genomic DNAs cloned in high-capacity vectors. - [Read Direct Selection of cDNAs with Large Genomic DNA Clones Protocol]
Protocol describes how to identify cloned cDNAs encoding proteins that bind to specific DNA sequences. The methods used are very similar to those used for immunological screening of expression libraries except that the nitrocellulose filters carrying immobilized proteins are screened with 32P-labeled double-stranded DNA rather than with antibodies. - [Read Identifying DNA-binding Proteins in Bacteriophage ambda Expression Libraries Protocol]
Includes: Isolation of Arabidopsis LEU2 cDNAs by complementation of the yeast leu2 mutation; Recovery of plasmid DNA from yeast cells; Analysis of Arabidopsis cDNAs that complement a yeast leu2 mutation; Preparation of library DNA from the Lacroute cDNA library; Preparation of Yeast Media. - [Read Isolation of Arabidopsis cDNAs by Complementation in Yeast]
The preparation of expressional cDNA libraries for use in the yeast two-hybrid system is quick and efficient when using the dedicated Clontech™ product, the MATCHMAKER Library Construction and Screening Kit 3. This kit employs SMART technology for the amplification of full-length cDNAs, in combination with cloning using homologous recombination. - [Read Isolation of Plant Transcription Factors Using a Modified Yeast One-Hybrid System]
Protocol describes the production of double-stranded RNA (dsRNA) from fragments of cDNAs of candidate genes. The cDNA fragments must be cloned in plasmids with a flanking SP6 and T7 promoter (e.g., pSP72 or pCRII). The plasmid is linearized and sense and antisense RNAs are produced separately by in vitro transcription. After purification, the RNA strands are annealed to yield a dsRNA molecule suitable for RNAi in avian embryos. - [Read Production of dsRNA for RNAi in Avian Embryos Protocol]
Protocol describes the production of double-stranded RNA (dsRNA) from fragments of cDNAs of candidate genes. The cDNA fragments must be cloned in plasmids with a flanking SP6 and T7 promoter (e.g., pSP72 or pCRII). The plasmid is linearized and sense and antisense RNAs are produced separately by in vitro transcription. - [Read Production of dsRNA for RNAi in Avian Embryos Protocol]
Protocol details the preparation of fluorescently labeled target samples and hybridization of these samples to a microarray of Agilent inkjet-deposited cDNAs. The procedure requires a minimum of 5 mg of purified total RNA as starting material. Includes: First Strand cDNA Synthesis; Second Strand cDNA Synthesis; cDNA Cleanup and Precipitation; In vitro Transcription; Cleanup and Quantification of in vitro Transcribed RNA; Fluorescent Labeling of the Target Samples. - [Read Transcript Profiling by Microarray Analysis Protocol.]
Protocol details the preparation of fluorescently labeled target samples and hybridization of these samples to a microarray of Agilent inkjet-deposited cDNAs. The procedure requires a minimum of 5 mg of purified total RNA as starting material. - [Read Transcript Profiling by Microarray Analysis—Agilent Protocol]
In this stage of the protocol, a mammalian cDNA library constructed in a plasmid such as pJG4-5 is transformed into yeast strains containing pBAIT and the lexAop-lacZ reporter plasmid. PJG4-5 expresses the cloned cDNAs from a cassette containing a transcriptional activation domain and other moieties under the control of the yeast GAL1 promoter. - [Read Two-hybrid Systems Stage 2: Selecting an Interactor Protocol]