cDNA clones are protein-coding DNA sequences reverse transcribed from mature mRNA and inserted into plasmid vectors for propagation and expression. Gene-specific cDNA are often used in the heterologous expression of a desired gene in another organism (i.e., in a cell line or in bacterial culture) for investigations in gene expression or protein structure and function. Conveniently, several commercial sources now provide detailed catalogues of specific cDNA and open reading frames (ORFs) already cloned in vectors. Some clones feature CMV and SV40 promoters for ready expression in mammalian cells, as well as different epitope and purification tags. Some clones are also provided in either glycerol stock or purified DNA. To find your desired cDNA clone, simply enter in the gene name or symbol within the search bar.