Control of the expression of anchored genes using micron scale heater

We control in vitro gene expression, using DNA (gene) sequences immobilized on miniaturized heaters. For this, electronically addressable indium-tin-o xide heating pads, 100 mu m(2) in size, are fabricated on a glass substrate to locally define temperatures and thus control transcription and translat ion of DNA gene sequences attached to the pad. Wheat germ cell extract is t he reaction medium. We use luciferase gene and monitor its temperature-cont rolled expression by luminescence. Various constructs are tested yielding e ither luciferase free or bound to the coding DNA. Control of protein produc tion at precise sites and rates, using temperature, opens the possibility t o engineer various protein networks with different time scales. Working wit h constructs where the protein stays bound, gene product micro-arrays can b e realized. (C) 2000 American Institute of Physics. [S0003-6951(00)04424-7] .