Nucleic Acid Aptamer Selection for Myelin Basic Protein for the Prevention of Malignant Schwann Cells by Manjari Subramanian

Myelin basic protein (MBP) promotes growth of myelin sheath throughout the nervous system by binding to the lipids on the myelin membrane (Boggs, 2006). However when a malignant cell is formed, the abnormal cell inhibits the transmission of electric signals across synapses (Kaur et al., 2008). MBP has the ability to distinguish the difference between a normal and malignant Schwann cell due to deletions within the MBP gene sequence (Kaur et al., 2008).

Figure 1 Myelin Basic Protein: Computer model of the protein. Human myelin basic protein by binding it to a leukocyte antigen (Smith et al., 1998).
Aim 1: Select for the protein  
            A multi-layered process will be involved in the selection for MBP. Aptamers, used as RNA protein markers in this case, will be selected for myelin basic protein. Aptamers bind to proteins with high specificity and affinity to the specific protein target. This is because aptamers are about one-tenth the size of an antibody (Boggs, 2006). This provides a set of tools that aid in area of therapeutic diagnostics in medicine. MBP itself is not a large protein (only 18.5 kDa); thus using an aptamer, which is even smaller, will increase chances of binding to the protein (Saxe et al., 1985). By selecting for MBP, the gene sequence of the protein can be verified before further development of an aptamer to distinguish between a normal and malignant cell. If successful, further tests can be conducted to see if the aptamer can deliver a drug or select against a mutate MBP. The first step is to find an aptamer that binds to this specific protein.

The target can be ordered from US Biologicals at $327.00 per milligram and $2.40 per round (400pmol).
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