Engineering
Background
Parkinson’s disease affects more than 4 million people worldwide. In the United
States, Parkinson’s disease occurs in approximately 13 per 100,000 people, and about 60,000 new cases are
identified each year. With more people living longer than before, the number of people who can get this
disease is expected to increase in the coming decades. Parkinson's disease is highly senile, and this
disease has seriously threatened the health of elderly people. This disease leads to a gradual loss of
physical motor function, lethargy, inconvenience, and slowness of movement. At the same time, patients will
also have different degrees of depression and anxiety symptoms. There is an urgent need for medical
treatments that are both effective and affordable for the majority of the aged population. However, the
current medication cannot satisfy the demand for most aged population, since it only relieves the symptom
and maintains the life quality of the patients to some extent.
Design
During our process of reading massive public literature on the matter, we came
across a relatively new target, angiogenin (ANG) protein, a secreted ribonuclease. According to the
literatures, angiogenin has been recognized to play important roles in various physiological and
pathological processes, especially in neurodegenerative diseases. The loss-of-function mutation of the ANG
gene is likely to be an important cause of certain nervous system diseases such as Parkinson’s disease.
Therefore, we realized that the delivery of active angiogenin protein could reduce neurodegeneration and
could possibly be used as a clinical treatment once we correctly inject the protein.
In our project, we aim to create a recombinant bacteria that can secret functional
ANG protein, which could possibly serve as an in vitro method to massive produce ANG for clinical use.
Build
pET-28a-rANG which produces ANG protein is shown in Figure 1.
Figure 1. Schematic map of pET-28a-rANG plasmid and its construction.
Test
We have obtained Freeze-dried powder of the ANG protein produced by our engineered
Escherichia coli (Figure 2).
Figure 2. Freeze-dried powder of the ANG protein.
The activity of recombinant ANG protein was determined by the RNA degradation
assay. The result indicated that ANG protein possesses ribonuclease activity as we expected.
Figure 3. RNA degradation by ANG.