• Analyze tissue-specific gene expression
  • Isolate the true 5’ and 3’ ends of messages
  • Identify tissue specific splice variants
  • cDNAs from various mouse and human tissues available

FirstChoice® cDNAs significantly reduce the amount of time and effort required for tissue-specific cloning and gene expression analyses. FirstChoice cDNAs are available in RACE-Ready and PCR-Ready formats that were developed specifically to simplify RACE and PCR applications.

Better Results With Longer cDNA

FirstChoice RACE- and PCR-ready cDNA products begin with the same high quality FirstChoice Poly(A) RNA and are a mixture of cDNA populations separately primed with random decamers and oligo(dT). The RNA is converted into first strand cDNA by an engineered M-MLV reverse transcriptase, ArrayScript (patent pending), that produces high yields of full-length cDNA (Figure 1). The increased length of a mixed cDNA population should be especially beneficial to researchers needing to identify the 5’ or 3’ ends of messages, characterize genetic isoforms and splice variants, or construct cDNA libraries. Both cDNAs are purified identically, but the RACE-Ready cDNAs undergo additional pre-cDNA synthesis processing to maximize representation of end sequences.

Figure 1. Longer Average cDNA Length After Reverse Transcription Using ArrayScript™. cDNAs were prepared from 2–7 µg (after adapter ligation; for RACE-Ready) or 5 µg (for PCR-Ready) of FirstChoice® Poly(A) RNA. RNA was reverse transcribed using either wild type M-MLV RT (200 U/µl) or ArrayScript RT (200 U/µl), and oligo(dT) primers (A) or random decamers (B). After column purification to remove primers and small reaction products, cDNA length was assessed using an Agilent® 2100 bioanalyzer. The data represent the average cDNA length for 8 samples. All samples showed an increase in length when reverse transcribed with ArrayScript RT. Average length varied with species, tissue, and RT primer used. Average cDNA lengths were 31–93% longer when primed with oligo(dT) (A) and 7–15% longer when primed with random decamers (B). As expected, the increase in average cDNA length is smaller for random primed products, because primers that anneal close to the termini can only produce finite-sized cDNAs.

Application Ready cDNAs

FirstChoice PCR-Ready cDNAs contain sufficient cDNA for 50 PCR reactions and are supplied with control primers. Both PCR-Ready cDNA and RACE-Ready cDNA can be used for routine PCR, but PCR-Ready cDNA is a more economical choice, with no compromise in performance. FirstChoice RACE-Ready cDNAs contain cDNA for 30 RLM-RACE reactions and include adapter primers for both 5’ and 3’ end-specific amplification and controls. Both FirstChoice RACE-Ready and PCR-Ready cDNAs are available from a variety of human and mouse tissues.