Deletions on chromosome 16 at the 16p11.2 region result in autism in a small portion of the general population. Major vault protein (MVP) is a gene within this region.
Paul Lombroso and his colleagues at Yale University showed that MVP is associated with messenger RNAs (mRNAs), which transport genetic information during the formation of proteins, and is also found throughout neurons. It is present in nuclei, along dendrites (the signal-receiving ends of neurons), and in synapses (the junctions between neurons) and growth cones (the growing portions of neuronal tips).
Lombroso and his team aimed to determine whether the absence of MVP leads to a decrease in the transportation of mRNAs along dendrites. To test the hypothesis, the group analyzed mRNAs from MVP knock-out mice after isolating the subcellular compartment of neurons that are enriched in synapses and where mRNA have previously been found to localize prior to being translated into proteins.
The researchers’ results indicate that mRNA levels are disrupted within synaptosomal fractions of mice that lack MVP. The findings differ from Lombroso’s original hypothesis in that he and his colleagues found that some mRNAs are elevated while others are decreased.