Apolipoproteinum E

Apolipoproteinum E
Alia nomina	ApoE, APOE, APO-E, LDLCQ5, LPG, ApoE4
Locus geni (homo)

Chromosoma	19 (humanum)
Locus	19q13.32 (homo)

Fontes externae	OMIM: 107741

Apolipoproteinum E (ApoE abbreviatum) est proteinorum classis metabolismi lipidorum. Lipoproteinum ApoE e lipidis aminoacidis formatum est.

Nomen geni eius, quod in hominibus in chromosomate 19 invenitur, APOE est. Polymorphismi ApoE noti sunt: adhuc variantia genorum allela tria (et tres isoformae), APOE-ε2 (ApoE2), -ε3 (ApoE3), -ε4 (ApoE4), et alia investigata sunt. Omnibus 299 aminoacidorum sunt^[1].

ApoE transportator imprimis triglyceridorum et minus cholesteroli momentum maximum habet, velut in diversis morbis ut morbo Alzheimeriano, dysbetalipoproteinaemia familiari (typus III hyperlipoproteinaemiarum)^[2], lipoproteinis glomerulopathia (LPG).

Genetica

Genum nomine APOE in hominibus in chromosomate 19 (19q13.32) situm est. Tria allela geni, epsilon 2 (ε2), epsilon 3 (ε3), epsilon 4 (ε4), tria isoforma apolipoproteini E, ApoE2 enim et ApoE3 et ApoE4, formant^[3]. Allelum ε3 frequentissimum (78%) videtur, dehinc putatur forma initialis.

Frequentia allelorum
ε2	ε3	ε4
8%	78%	14%

Structura

ApoE est lipoproteinum, quod est ApoE ex lipidis et proteino constitutum est. Proteino 299 aminoacidorum sunt, cuius funiculus multiplices α-helices amphipathicae (cum residuis aminoacidorum et polaribus et non polaribus) format (vid. imaginem)^[4].

Physiologia

Structura chylomicroni cum apoproteinis ut ApoE. T = triglycerida, C = cholesterolum.

Apolipoproteina E apoproteina chylomicronorum cum receptoriis superficei hepatocytorum se coniungunt.

Chylomicrona et ApoE

Conferatur pagina principalis: chylomicronum.

Chylomicrona sunt particulae sanguinieae cum triglyceridis et cholesterolo ex intestino orientia. In sanguine chylomicrona lipoproteina altae densitatis (HDL, particulae parvissimae lipoproteinorum) accipiunt. Demum superficie hepatocytorum apolipoproteina transgressionem lipidorum ex chylomicrono intra hepatocytos funguntur.

Notae

↑ Rall S. C. Jr., Weisgraber K. H., Mahley R. W. (1982). "Human apolipoprotein E. The complete amino acid sequence". The journal of biological chemistry 257 (8): 4171-8
↑ Smelt A. H., de Beer F. (2004). "Apolipoprotein E and familial dysbetalipoproteinemia: clinical, biochemical, and genetic aspects". Seminars in vascular medicine 4 (3): 249-57
↑ Rall S. C. Jr., Weisgraber K. H., Innerarity T. L., Mahley R. W. (1982). "Structural basis for receptor binding heterogeneity of apolipoprotein E from type III hyperlipoproteinemic subjects". PNAS 79 (15): 4696-700
↑ Phillips M. C. (2014). "Apolipoprotein E isoforms and lipoprotein metabolism". IUBMB Life 66 (9): 616-23

Nexus interni

[1] Rall S. C. Jr., Weisgraber K. H., Mahley R. W. (1982). "Human apolipoprotein E. The complete amino acid sequence". The journal of biological chemistry 257 (8): 4171-8

[2] Smelt A. H., de Beer F. (2004). "Apolipoprotein E and familial dysbetalipoproteinemia: clinical, biochemical, and genetic aspects". Seminars in vascular medicine 4 (3): 249-57

[3] Rall S. C. Jr., Weisgraber K. H., Innerarity T. L., Mahley R. W. (1982). "Structural basis for receptor binding heterogeneity of apolipoprotein E from type III hyperlipoproteinemic subjects". PNAS 79 (15): 4696-700

[4] Phillips M. C. (2014). "Apolipoprotein E isoforms and lipoprotein metabolism". IUBMB Life 66 (9): 616-23

[1]

[2]

[3]

[4]