DNA Microarray technologies & PNA

This project includes the use of DNA microarray technologies which has allowed them to interface DNA arrays with combinatorial libraries. PNA-encoded libraries were developed and successful used to study kinases and proteases for the very first time by Juanjo and Laurent Bialy, an important mention goes to Lise Keinicke. Currently 10,000 member libraries are being tested in order to profile different enzymes while other PNA-encoded strategies are being developed. One of the ongoing projects is the use of cell-based microarrays. Following the successful application of reverse transfection microarrays to study transfection agent libraries and the experience achieved by the Bradley group in the development of polymer arrays , collaborations with Tim Elliot and Salim Khakoo are underway to exploit the huge potential of this technology.

Figure 1. PNA-encoded libraries. From solution assays to 2D microarrays.

Figure 2. Hybridization of a 10,000 member PNA-encoded library using a custom OGT DNA microarray.

Figure 3. Cells adhered onto a microarray spot. Different detection systems can be used such as fluorescently labelled antibodies.

Peptide Nucleic Acid (PNA): Novel Applications in HTS

PNA are well-known DNA mimetics which hybridise complementary DNA sequences with higher affinity than their DNA counter-parts. While DNA has a sugar-phosphonate backbone, PNA has a 2-aminoethylglycinate one.

The synthesis of new protected PNA monomers has been developed, thus allowing the solid-phase synthesis of various PNA conjugates. The aim of the project involves the use of these conjugates in a wide range of applications, for example antisense and antigene bio-assays and High Throughput Screening (HTS) by utilising DNA microarray technology. The Group has acquired the complete equipment to make and analyse its own DNA or PNA chips. This equipment includes a Genetix QArrayMini Microarray and a LaVision BioTech Bioanalyzer 4F/4S Scanner (white-light source coupled to a CCD camera).

High density OGT custom DNA microarray hybridised with a synthetic PNA encoded peptide library (10,000 members)