Sandbox Reserved 815: Difference between revisions
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=3HAF DOMAIN | =3HAF DOMAIN OF HUMAN PRION: Overview= | ||
[[Image:3haf bio r 500.jpg|left|220px|thumb|'''3HAF Domain-Dimer''']] | [[Image:3haf bio r 500.jpg|left|220px|thumb|'''3HAF Domain-Dimer''']] | ||
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Human prion is a membrane protein of 16284.86 Da. The infectious agent penetrates the neuron and due to reasons and mechanisms still misunderstood, it multiplies, by opening/folding normal proteins in pathogenic prions. This new form cannot be degraded by proteolysis and the aggregation of misfolded proteins induces the death of cells and the accumulation of [http://en.wikipedia.org/wiki/Amyloid amyloid plaques] in the brain. | Human prion is a membrane protein of 16284.86 Da. The infectious agent penetrates the neuron and due to reasons and mechanisms still misunderstood, it multiplies, by opening/folding normal proteins in pathogenic prions. This new form cannot be degraded by proteolysis and the aggregation of misfolded proteins induces the death of cells and the accumulation of [http://en.wikipedia.org/wiki/Amyloid amyloid plaques] in the brain. | ||
3HAF is a | 3HAF is a variant domain of the [http://www.proteopedia.org/wiki/index.php/Human_Prion_Protein_Dimer major protein prion] going from residue 90 to 231. Compare to the sequence of the major prion protein, a Valine substitutes a Methionine at the 129 residue, which influence the susceptibility of the formation of the prion. | ||
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The protein exists in majority in its dimer form. | The protein exists in majority in its dimer form. | ||
Between each <scene name='User:Erin_May/Sandbox_1/Nonpolar_at_dimer_interface/2'> helix 144-156</scene> of the two proteins, it exists many interactions whose stabilize the dimer interface. It can be retain acidic and mostly negative residues, or basic and positive residues. | Between each <scene name='User:Erin_May/Sandbox_1/Nonpolar_at_dimer_interface/2'> helix 144-156</scene> of the two proteins, it exists many interactions whose stabilize the dimer interface. It can be retain acidic and mostly negative residues, or basic and positive residues. | ||
Each | Each monomere is linked to the C-terminal <scene name='User:Erin_May/Sandbox_1/Helix_2_with_helix_3/1'> helix 200-225</scene> of the other one. [http://en.wikipedia.org/wiki/Van_der_Waals_forces Van der Waals] forces are here between such nonpolar residues as Valine, Isoleucine, and nonpolar sections as Histadine, Methionine, and Glutamic acid. | ||
It occurs hydrogen | It occurs hydrogen bonds between the dimers at <scene name='User:Erin_May/Sandbox_1/Interface_hydrogen_bonding/1'> Thr188 O Gly195 N</scene>, Thr190 O−Lys194 N and Thr192 O−Thr192 N. | ||
On each monomer, a hydrogen bond between <scene name='User:Erin_May/Sandbox_1/Hydrogen_bond_asp_202/1'> Asp 202 and Thr 199</scene> stabilizes the dimeric structure. | On each monomer, a hydrogen bond between <scene name='User:Erin_May/Sandbox_1/Hydrogen_bond_asp_202/1'> Asp 202 and Thr 199</scene> stabilizes the dimeric structure. | ||
<scene name='User:Erin_May/Sandbox_1/Hydrogen_bonding/1'> Arg 220 and Ser 132</scene> form a hydrogen bond located at the end of helix 3 which permit inter-chain interactions to be specific. | <scene name='User:Erin_May/Sandbox_1/Hydrogen_bonding/1'> Arg 220 and Ser 132</scene> form a hydrogen bond located at the end of helix 3 which permit inter-chain interactions to be specific. | ||