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Inverse PCR - Can I use cDNA to do ipcr? (Jan/04/2008 )

Hi everyone,
Does anybody know if I can use cDNA for inverse pcr? I have a know sequence from my ORF but need the surrounding sequence. I don't want to sequence the entire gene so I thought I might be able to use just cDNA as a template. Could I just circularize the cDNA using T4 ligase and the amplify with inverse primers? Any suggestions are appreciated. Thanks

-jennifer6271-

Is this single stranded cDNA or already amplified?

-vairus-

QUOTE (vairus @ Jan 4 2008, 01:23 PM)
Is this single stranded cDNA or already amplified?


This would be mRNA from cell culture converted to cDNA

-jennifer6271-

Why not try the regular inverse PCR-technique? since you know the sequence of your ORF, just cut your genomic DNA with an enzyme (or 2 different enzymes with compatible ends) that cuts halfway in your ORF and "often enough" in the genomic DNA (an enzyme that has a recognition sequence of 6 bp cuts once every 4096bp in theory). Ligate this mixture in a large volume (you want to have as much self-ligation as possible) and then amplify with primers facing outwards from the recognition site. This should amplify your ORF + the surrounding part (untill the site where the restrictions took place) that you can then sequence.

-vairus-

QUOTE (vairus @ Jan 5 2008, 05:02 AM)
Why not try the regular inverse PCR-technique? since you know the sequence of your ORF, just cut your genomic DNA with an enzyme (or 2 different enzymes with compatible ends) that cuts halfway in your ORF and "often enough" in the genomic DNA (an enzyme that has a recognition sequence of 6 bp cuts once every 4096bp in theory). Ligate this mixture in a large volume (you want to have as much self-ligation as possible) and then amplify with primers facing outwards from the recognition site. This should amplify your ORF + the surrounding part (untill the site where the restrictions took place) that you can then sequence.



I was just trying to avoid sequencing large pieces of DNA and then dealing with mapping intron/exon boundaries. Thought someone might know of a way to use cDNA instead. I am only interested in getting the coding region of my gene. Thanks for your input

-jennifer6271-