Modified primers

A new technique for preparing fluorescent cDNA probes will allow microarray analysis of smaller RNA samples.

Jonathan Weitzman(
Jun 30, 2002

A limiting aspect of microarray experiments is the efficient production of labelled cDNA probes from small amounts of starting material (typically over 20 μg of total RNA is required) . In the July issue of Nature Biotechnology, Charlie Xiang and colleagues describe a technique for efficient and inexpensive probe production using random hexamer oligonucleotide primers that have been modified with free amino groups at their 5' ends (Nat Biotechnol 2002, 20:738-742).

This method allows for the generation of fluorescent probes for microarray hybridization using as little as 1 μg of total RNA. They used random primers with 5' amino C6dT (thymidine modified at the 5' position with an 8-9 carbon chain ending in a primary amine) and incorporated aminoallyl-dUTP during cDNA synthesis. The fluorescent dyes (Cy3 and Cy5) were then chemically added to the free amino groups.

Xiang et al. used microarray experiments to demonstrate that...

Interested in reading more?

Become a Member of

Receive full access to more than 35 years of archives, as well as TS Digest, digital editions of The Scientist, feature stories, and much more!
Already a member?