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The second and third paper are the most pertinent to my project, as they both deal with NPC2 directly. As such, there is a great deal of overlap, and it is more efficient to deal with them at once. Also, rather than have parts on different pages, it is better to have the summary on one page. In addition, I will expand my bioinformatics main page to include selected parts of this page. To view the second paper or third paper directly, click on the provided links.

The third paper, written by Dr. HG and her colleagues, provides a list of the most important phrases and ideas: Niemann-Pick Type C, NPC2, Phylogenetic analysis, Homology Modeling, and Conservation Mapping. I will attempt to phrase my summary in these terms, defining them as definitively as possible when I do so.

Niemann-Pick Type C
As I mentioned in my summary of the first paper, this is a neurodegenerative disease in which lipids (specifically cholesterol) cannot be properly moved out of the central nervous system (CNS), as well as other major organs, such as the liver and the spleen. This progressively causes mass cell death and usually results in the death of the patient by early adulthood. Type C has been identified with two primary proteins, NPC1 and NPC2. 95% of cases are identified with NPC1, but the remaining 5% resulting from errors in NPC2 are indistinguishable. This strongly suggests that the two proteins directly interact, and that neither functions without the other. How they do this, however, remains undetermined.

NPC1 and 2
NPC1: A relatively large transmembrane protein that is usually located in the late endosomes (see previous entries for greater detail). NPC2: a smaller, soluble glycoprotein, it facilitates primarily cholesterol (but also other lipids) egress from the endosomal/lysosomal compartment, and plays a role in regulating homeostasis. It has five regions of interest, including a hydrophobic "knob" most likely involved in membrane interaction, the cholesterol binding region itself, and three faces that are likely involved in mediating separate interactions.