The selected aptamer shows specific binding to the target protein (red) with clear distinction of the counter target (blue) which only differs by two PTMs (citrullination = PTM by deimination of arginine). No binding is seen towards the negative control protein (grey).
The development of high-quality affinity reagents with strict discrimination between the desired target protein and closely related peptides represents a major challenge in basic and applied biomedicine. Many large-scale biological assays rely on the use of antibodies to interrogate the nature and function of the human proteome. Unfortunately, only a small portion of human proteins have antibodies that are available for use in routine molecular and cellular biology assays. Even less common are antibodies with high affinity and specificity to specific post-translational modifications (PTMs) and caution is often urged when using antibodies to detect modified proteins in biological samples.
At Aptamer Group, we addressed this challenge and tailored our selection processto include customer requirements and enable the selection of very specific aptamers that also can detect PTMs and distinguish their occurrence in a protein.