New pUC-derived expression vectors for rapid construction of cDNA libraries

We have constructed a new series of the pUC-derived plasmids with an extended polylinker obtained from M13tg131 [Kieny et al., Gene 26 (1983) 91–99]. These vectors allowed us to design a simplified version of the method of Okayama and Berg [Mol. Cell. Biol. 2 (1982) 161–170] for establishing complete cDNA libraries. Improvements included (i) easy recovery of the inserted cDNA due to the extended Polylinkers; (ii) use of these vectors for gene expression in Escherichia coli, and (iii) amenability to supercoil sequencing with the universal primers of the M13 system [Chen and Seeburg, DNA 4 (1985) 165–170], which speeds up the identification of positive clones. Moreover, there is no need for an additional linker fragment, as was required by the Okayama and Berg [Mol. Cell. Biol. 2 (1982) 161–170] method. We have successfully used this system to obtain cDNA clones coding for the different chains of the large basement membrane proteins type IV collagen and laminin.