Saposin: Difference between revisions
From Proteopedia
Jump to navigationJump to search
Michal Harel (talk | contribs) No edit summary |
Michal Harel (talk | contribs) No edit summary |
||
| (6 intermediate revisions by 2 users not shown) | |||
| Line 1: | Line 1: | ||
<StructureSection load='2dob' size='350' side='right' scene='' caption='Human saposin A complex with Ca+2 [[2dob]]'> | |||
== Function == | == Function == | ||
'''Saposin''' (Sap) is a small protein which functions as activator of lipid-degrading enzymes. They act by isolating the lipid substrate from the membrane. Sap is synthesized as a precursor – prosaposin – which contain 4 SapB active domains (cleaved to saposin A,B,C and D) and 2 SapA domains which are cleaved off<ref>PMID:2001789</ref>. | '''Saposin''' (Sap) is a small protein which functions as activator of lipid-degrading enzymes. They act by isolating the lipid substrate from the membrane. Sap is synthesized as a precursor – prosaposin – which contain 4 SapB active domains (cleaved to saposin A,B,C and D) and 2 SapA domains which are cleaved off<ref>PMID:2001789</ref>. See also [[Lipid metabolism]]. | ||
*'''Saposin A and C''' stimulate hydrolysis of methylumbelliferyl β-galactoside by β-glucosylceramidase and of galactocerebrocide by β-galactosylceramidase<ref>PMID:2717620</ref>. For more details see [[Molecular Playground/Saposin C]].<br /> | *'''Saposin A and C''' stimulate hydrolysis of methylumbelliferyl β-galactoside by β-glucosylceramidase and of galactocerebrocide by β-galactosylceramidase<ref>PMID:2717620</ref>. For more details see [[Molecular Playground/Saposin C]].<br /> | ||
| Line 9: | Line 9: | ||
== Disease == | == Disease == | ||
Mutations in saposin B are autosomal recessive trait resulting in clinical metachromatic leukodystrophy<ref>PMID:17616409</ref>. Mutations in saposin D cause urinary system defects<ref>PMID:15345707</ref>. | Mutations in saposin B are autosomal recessive trait resulting in clinical metachromatic leukodystrophy<ref>PMID:17616409</ref>. Mutations in saposin D cause urinary system defects<ref>PMID:15345707</ref>. | ||
</StructureSection> | |||
== 3D Structures of Saposin == | == 3D Structures of Saposin == | ||
| Line 15: | Line 15: | ||
{{#tree:id=OrganizedByTopic|openlevels=0| | {{#tree:id=OrganizedByTopic|openlevels=0| | ||
*Saposin A | *Saposin A residues 60-143 | ||
**[[2dob]] – hSapA | **[[2dob]], [[4uex]] – hSapA – human<br /> | ||
**[[4ddj]] – hSapA + LDAO<br /> | **[[4ddj]] – hSapA + LDAO<br /> | ||
**[[7p4d]] – mSapA – mouse<br /> | |||
**[[5nxb]] – mSapA + galactocerebrosidase <br /> | |||
*Saposin A residues 1-81 | |||
**[[6d80]] – hSapA + mitochondrial calcium uniporter<br /> | |||
*Saposin B | *Saposin B | ||
**[[1n69]] – hSapB + lipid | **[[1n69]] – hSapB + lipid<br /> | ||
**[[4v2o]] – hSapB + chloroquine<br /> | |||
*Saposin C | *Saposin C | ||
| Line 32: | Line 39: | ||
**[[3bqp]], [[3bqq]], [[2r1q]], [[2rb3]] - hSapD residues 405-484<br /> | **[[3bqp]], [[3bqq]], [[2r1q]], [[2rb3]] - hSapD residues 405-484<br /> | ||
**[[5u85]] - mSapD residues 438-519<br /> | |||
}} | }} | ||
== References == | == References == | ||
<references/> | <references/> | ||
[[Category:Topic Page]] | [[Category:Topic Page]] | ||
