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== Clinical Significance ==
== Clinical Significance ==
===Drug Development===
===Drug Development===
[https://en.wikipedia.org/wiki/Pramlintide Pramlintide] is a synthetic analog of amylin that is commonly used in accordance with mealtime [https://en.wikipedia.org/wiki/Insulin insulin] to help treat type 1 and 2 diabetic patients <ref name="Hay"/>. This drug binds to AMYR competitively, increasing the AMYR GPCR signaling. Increased action of the AMYR receptor has been shown to modestly lower HbA1c levels, which is often accompanied by weight loss <ref name="Hoogwerf">PMID: 18561511</ref>. Pramlintide binds with more affinity than amylin due to mutations from hydrophobic residues A29, S28, S29, and S37 to proline. The proline residues increase the rigidity of the ligand by creating unfavorable phi and psi angles, which improves the ability of the ligand to bind AMYR. Pramlintide treatment has also been shown to consistently reduce [https://en.wikipedia.org/wiki/Amyloid_plaques Amyloid β plaque] aggregation in rodent models with [https://en.wikipedia.org/wiki/Alzheimer%27s_disease Alzheimer’s disease] <ref name="Gingell">PMID:24169554</ref>.
[[Image:align.png|300px|left|thumb|Figure 2:Amylin (green) aligned with Pramlintide (red)]] [https://en.wikipedia.org/wiki/Pramlintide Pramlintide] is a synthetic analog of amylin that is commonly used in accordance with mealtime [https://en.wikipedia.org/wiki/Insulin insulin] to help treat type 1 and 2 diabetic patients <ref name="Hay"/>. This drug binds to AMYR competitively, increasing the AMYR GPCR signaling. Increased action of the AMYR receptor has been shown to modestly lower HbA1c levels, which is often accompanied by weight loss <ref name="Hoogwerf">PMID: 18561511</ref>. Pramlintide binds with more affinity than amylin due to mutations from hydrophobic residues A29, S28, S29, and S37 to proline. The proline residues increase the rigidity of the ligand by creating unfavorable phi and psi angles, which improves the ability of the ligand to bind AMYR. Pramlintide treatment has also been shown to consistently reduce [https://en.wikipedia.org/wiki/Amyloid_plaques Amyloid β plaque] aggregation in rodent models with [https://en.wikipedia.org/wiki/Alzheimer%27s_disease Alzheimer’s disease] <ref name="Gingell">PMID:24169554</ref>.


It has been thought that [https://en.wikipedia.org/wiki/Missense_mutation missense mutations] in residues C2 and C7 ​of the amylin peptide could lead to an increased risk of Alzheimer's Disease (CITE) <ref name="Grizzanti">PMID: 30282360</ref>. Because of the rigidity these cysteine resides provide, reductions of their disulfide interaction leads to an increased risk of amyloid plaques due to amylin misfolding and forming aggregates. During drug design, pharmaceutical companies have focused on maintaining amylin residues C2 and C7, as well as K1, which forms a hydrogen bond donor for the <scene name='10/1038828/N_term_disulfidenew/1'>E294 Side Chain</scene> and main chain carbonyl. Additionally, pharmaceuticals companies have also opted to maintain residues <scene name='10/1038819/Amidated_c_term/9'>Y37 and T36</scene>, which are critical residues in stabilizing the C terminus of amylin to the receptor binding site. While there are hardly any differences in the helical portion of amylin and the synthetic analogue pramlintide, there is a difference in the extended random coil at the C terminus.  
It has been thought that [https://en.wikipedia.org/wiki/Missense_mutation missense mutations] in residues C2 and C7 ​of the amylin peptide could lead to an increased risk of Alzheimer's Disease (CITE) <ref name="Grizzanti">PMID: 30282360</ref>. Because of the rigidity these cysteine resides provide, reductions of their disulfide interaction leads to an increased risk of amyloid plaques due to amylin misfolding and forming aggregates. During drug design, pharmaceutical companies have focused on maintaining amylin residues C2 and C7, as well as K1, which forms a hydrogen bond donor for the <scene name='10/1038828/N_term_disulfidenew/1'>E294 Side Chain</scene> and main chain carbonyl. Additionally, pharmaceuticals companies have also opted to maintain residues <scene name='10/1038819/Amidated_c_term/9'>Y37 and T36</scene>, which are critical residues in stabilizing the C terminus of amylin to the receptor binding site. While there are hardly any differences in the helical portion of amylin and the synthetic analogue pramlintide, there is a difference in the extended random coil at the C terminus. [[Image:pram sequence align.png|300px|right|thumb|Figure 3:Pramlintide Sequence alignment with varying forms of amylin. Atoms C2—C7 and K1 of the N-terminal region are conserved​. Y37 and T36 of the C-terminal region are also conserved.]]


In order to restore basal amylin levels in mice, researchers have performed PEGylation, the addition of poly ethylene glycol, to amylin within residues 1-11 of the peptide, most likely at the two amine groups of K1<ref name="Guerreiro">PMID: 23818080</ref>. Administration of the modified amylin in mice showed evidence of reduced glycemia and prolonged action compared to endogenous amylin <ref name="Guerreiro"/>.  
In order to restore basal amylin levels in mice, researchers have performed PEGylation, the addition of poly ethylene glycol, to amylin within residues 1-11 of the peptide, most likely at the two amine groups of K1<ref name="Guerreiro">PMID: 23818080</ref>. Administration of the modified amylin in mice showed evidence of reduced glycemia and prolonged action compared to endogenous amylin <ref name="Guerreiro"/>.  
[[Image:align.png|300px|left|thumb|Figure 2:Amylin (green) aligned with Pramlintide (red)]]
[[Image:pram sequence align.png|300px|right|thumb|Figure 3:Pramlintide Sequence alignment with varying forms of amylin. Atoms C2—C7 and K1 of the N-terminal region are conserved​. Y37 and T36 of the C-terminal region are also conserved.]]




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Ben Whiteside, Andrew Helmerich, Mathias Vander Eide, Wayne Decatur