Isolation of the 5′-End of Plant Genes from Genomic DNA by TATA-Box-Based Degenerate Primers

We report a rapid and simple method for isolating the 5′-end of plant genes from genomic DNA by polymerase chain reaction (PCR) with TATA-box-based degenerate primers (TDPs). The TDPs were specially designed according to the TATA box, which is conserved in the promoter region of most plant genes. The unknown 5′-ends of several genes in different plants were isolated by PCR with gene-specific primers of the known core fragment and the TDPs. Our method does not require the arduous RNA manipulations and expensive enzyme treatments of the popular rapid amplification of cDNA ends (RACE) and its variants, and so could be a cheap practical alternative.