Patent ID: 6136569
Filing Date: 2000-10-24
Classification: C12N,C40B

Abstract:
A method of creating a cDNA library enriched in signal sequences which comprises:a) creating a full-length cDNA library comprised of cDNA cloning vectors containing both a first unique restriction site and a DNA promoter located 5' to a full-length cDNA;b) transcribing mRNA transcripts from the cDNA cloning vectors of the cDNA library;c) preparing random DNA oligonucleotide primers and reverse transcribing the mRNA transcripts to create cDNA fragments of the cDNA cloning vectors of the cDNA library;d) preparing the cDNA fragments of step c) for ligation, and ligating the cDNA fragments to an adapter oligonucleotide containing a second unique restriction site;e) digesting the adapter ligated cDNA fragments of step d) with a restriction enzyme which cuts at the first unique restriction site;f) isolating the digested cDNA fragments of step e) which are about 500 to 1000 base pairs in length; andg) ligating the isolated, digested cDNA fragments of step f) into an amylase expression vector previously digested so as to also contain the first and second unique restriction sites.