[Synthesis of the mature human interleukin-1(alpha) gene by amplification of an mRNA-cDNA duplex in vitro].

Mixture of polyadenylated mRNAs from human monocytes has been subjected to the reverse transcription specifically initiated from the mRNA encoding interleukin 1 alpha by a synthetic polynucleotide complementary to the mRNA's coding 3'-end to yield the corresponding mRNA-cDNA duplex. Under conditions of the polymerase chain reaction, with the above polynucleotide as a downstream primer and an upstream primer corresponding to the beginning of the mature interleukin 1 alpha (AA 113-271) gene, the mRNA-cDNA duplex yielded the desired gene, whose structure was proved by the restriction and sequence analyses. The gene, containing translation initiation and termination triplets, can be used for producing interleukin 1 alpha in various expression systems and as a probe in studies of the lymphokine's biosynthesis. This method of the gene synthesis does not need construction and analysis of cDNA libraries nor synthesis of double-stranded DNA, and can, in principle, make use of the total (non-fractionated) cellular RNA.