Overview of the production and use of Macroarrays. Macroarrays were constructed from cDNA held within bacterial libraries. These libraries were developed by inserting total human cDNA into bacteriophage vectors and transfection into bacteria. Pure colonies of bacteria carrying vectors were sequenced and amplified by PCR prior to spotting on to a macroarray. Samples were labeled by reverse-transcribing mRNA with radioactively labeled 33phosphate-deoxyribonucleotide triphosphates (33P-dNTPs) using specific oligo(dT) primers. Labeled cDNA samples were hybridized to duplicate macroarrays where gene expression was quantified by comparing the radio-emissions of each spot.
