Microarrays: The high-tech machinery

Robots and biotechnology research: Because the microarray process uses DNA and RNA molecules, which are tiny, sophisticated robots are required. Dr Bart Janssen from HortResearch shows off some of the machines and explains what they do.

Transcript

Dr Bart Janssen ( Plant & Food Research)

At the moment the machine at the end, which occasionally makes a large amount of noise, is printing on a microscope slide seventeen and a half thousand kiwi fruit genes in a very tightly ordered array. What it’s doing is putting a spot of DNA for each gene in exactly the same place on each microscope slide, and it’s going and getting another piece of DNA and spotting it right next to it. The spots are about 100 micrometres in diameter, and they’ve got about 50 micrometres in between each spot. It’s a very precise robot, and it's very patient because it will carry on doing that process for the next day and a half and from that we will get 65 microscope slides, each with seventeen and a half thousand genes printed on them. We will then take those microscope slides and then use the next robot in the system, and that will take each slide and hybridise it with RNA taken from samples that we’ve collected out in the field. It will do a series of washes and incubate the microscope slide over night. After that we will take it from that machine and put it in the final machine which is a laser scanner. That will scan all the seventeen and a half thousand spots on the mircoscope slide, and ask whether RNA has bound to that spot on the slide. And if RNA is bound, which RNA. So if we take two samples, one from a flower and one from a fruit, and we label them with different fluorescent labels, it will actually tell us whether fruit RNA bound here, or flower RNA bound, or both. It will display it on a computer here as a red, a green or a yellow spot.