This web page was produced as an assignment for Genetics 564, an undergraduate capstone course at UW-Madison.
What is Proteomics?
Proteomics is the study of the proteins. The location, abundance, and modifications of proteins that are present in a sample can reveal information about their function in a system and their role in disease. One way proteins can be studied is through post translational modifications (PTMs). PTMs are changes made to the protein after it is made within the cell. PTMs can affect the protein in a variety of ways, such as its activity rate, its location, and its longevity. Studying PTMs can give insight into the function of the protein, or identify the differences in PTMs between normal and disease-based proteins.
What is Phosphorylation?
Phosphorylation is one type of post translational modification. Phosphorylation consists of adding a phosphate to a protein to activate or deactivate it. Kinases are proteins that add phosphates to proteins, and phosphatases are proteins that remove phosphates from proteins. Kinases and phosphatases are often required to phosphorylate and dephosphorylate proteins to control the time at which they are active or allow/prevent proteins from interacting with each other. Phosphorylation occurs are specific amino acids within the protein, so identifying what domains these sites are located in can reveal more information about the protein's function. In some cases, aberrant phosphorylation can lead to disease, therefore it is important to identify the differences in phosphorylation patterns between the healthy and disease-state proteins. Furthermore, comparing the conserved phosphoryation sites among homologs can infer where phosphorylation is crucial for proper function.
Is SNRPN Phosphorylated?
Figure 1. Phosphorylation sites of human SNRPN. The vertical bars represent locations within the protein that are susceptible to phosphorylation. The height of each bar indicates the magnitude of phosphorylation potential, where taller bars are most likely to undergo phosphorylation.
Analysis
Across all four species above, there is a conserved high potential for phosphorylation within the Sm domain, which is implicated in RNA binding. This may indicate that phosphorylation is critical for proper RNA binding in SNRPN and its homologs, and therefore is required for functional mRNA splicing.
References
[1] NetPhos SNRPN human
[2] NetPhos SNRPN mouse
[3] NetPhos SNRPN zebrafish
[4] NetPohs SNRPN fly
[2] NetPhos SNRPN mouse
[3] NetPhos SNRPN zebrafish
[4] NetPohs SNRPN fly