Invitrogen launches first proteome array

Moroever, a set of human chips could be available in the autumn, with a humane proteome-wide array scheduled for launch in 2006. The availability of the chips should make it possible to use the yeast proteome to help map human disease gene pathways, as well as to assign functions to uncharacterised proteins.

This will dramatically speed up drug target identification, selection and validation, claims Invitrogen.

The interest surrounding the new chip - presented this week to the biotechnology industry at the BIO 2004 meeting in San Francisco, US - is reminiscent of that surrounding the launch of the first human genome microarrays which reached the market last year.

But while the genome microarrays have made it easier to identify the small disease-causing changes to human genes, Invitrogen believes the debut of proteome arrays will usher in a new age in functional genomics research, in which the functions of genes and their associated proteins can be explored.

"This high-throughput technology permits simultaneous and rapid screening of thousands of proteins in a miniaturised format that is compatible with standard laboratory equipment,"​ said Invitrogen. Proteins are much more difficult to work with than DNA, and this has held back the development of the tools needed to further proteomic research.

While there are about 30,000 human genes, it is estimated that the number of proteins in the proteome is much higher - at perhaps 100,000 or more. But the numbers do not even begin to illustrate the complexity - proteins can exist in diverse three-dimensional structures, change with age and are much tougher to work with.

Proteins are less stable than DNA, and tend to only function normally when they are in the correct 3D structure, so keeping their morphology intact when making the microarray has been one of the key hurdles for Protometrix, which was acquired by Invitrogen earlier this year.

Protometrix has effectively industrialised the process of cloning, expressing and purifying proteins, and binding them onto nickel-coated slides, coated with a silicone elastomer that helps support the proteins and keep them in a functional state.

At present, the only protein arrays on the market rely on the use of antibodies to detect limited numbers (20-30) of protein subsets, such as cytokines.

Invitrogen selected the yeast organism for its first array, as it is a frequently studied model for basic biological processes in humans with 50 per cent of yeast proteins having human counterparts - and 30 per cent of these nearly identical.

"Studying large groups of proteins with this detail and at this speed has not been possible until now,"​ said Gregory Lucier, Invitrogen's CEO.

In time, the company plans to develop more proteome arrays, such as the mouse, rat, dog, monkey, and other animals that are routinely used in drug-discovery labs.