Human lymphocyte cDNA ordered library analyzed by 2D gel electrophoresis. 2. Frequency distribution of mRNA populations.

Cell-free transcription and translation products from an ordered library of cDNA clones from the CEM human leukemic cell line were submitted to analysis using two-dimensional gel electrophoresis as a read out system. The matrix array of 24 x 16 x 12 wells contained in each of the positions lambda jacII phages from one plaque. Pools of clones along the three axes (24 x-pools, 16 y-pools and 12 z-pools) were established. Results obtained upon matching of 12 x-pools were scrutinized for estimating the frequency of cDNA molecular species in the library. The results obtained are interpreted in such a way that there are no discrete distributions of mRNA molecular species, but rather there is a continuous distribution of mRNA's covering a wide range of frequencies. The lowest frequency found was about 4.5 x 10(-4) and the highest 1.6 x 10(-2). About half of all clones can be found among these low frequency ones (each occurring 0.45 times among 1,000 clones).