UniProt functional annotation for P35844



	UniProt functional annotation for P35844

UniProt code: P35844.

Organism: Saccharomyces cerevisiae (strain ATCC 204508 / S288c) (Baker's yeast).

Taxonomy: Eukaryota; Fungi; Dikarya; Ascomycota; Saccharomycotina; Saccharomycetes; Saccharomycetales; Saccharomycetaceae; Saccharomyces.

Function: Lipid transporter involved in lipid countertransport between the Golgi complex and membranes of the endoplasmic reticulum: specifically exchanges sterol with phosphatidylinositol 4-phosphate (PI4P), delivering sterol to the Golgi in exchange for PI4P, which is degraded by the SAC1 phosphatase in the endoplasmic reticulum (PubMed:16136145, PubMed:22162133). Displays a similar affinity for PI4P and sterols (PubMed:22162133). Binds sterol and PI4P in a mutually exclusive manner (Probable). {ECO:0000269|PubMed:16136145, ECO:0000269|PubMed:22162133, ECO:0000305}.

Subcellular location: Golgi apparatus membrane {ECO:0000269|PubMed:11916983}.

Domain: Consists of a beta-barrel forming a sterol-binding pocket. When empty, the N-terminal lid (29 residues) is unfolded and leaves the pocket open. Upon sterol binding, this segment forms a lid that blocks the sterol molecule in the pocket (PubMed:16136145). Phosphatidylinositol 4-phosphate (PI4P) binding sites are roughly the same as for sterol. First, the sterol-binding pocket accommodates the PI4P acyl chains. Second, a shallow pocket at the entrance of the tunnel, which contains critical residues such as Lys-336, His-143 and His-144, selects the polar head of PI4P with high specificity. This interaction is probably essential for compensating loose binding of the PI4P acyl chains. Third, the N-terminal lid secures the bound PI4P molecule by wrapping its glycerol moiety (PubMed:22162133). {ECO:0000269|PubMed:16136145, ECO:0000269|PubMed:22162133}.

Miscellaneous: Present with 32200 molecules/cell in log phase SD medium. {ECO:0000269|PubMed:14562106}.

Similarity: Belongs to the OSBP family. {ECO:0000305}.

Annotations taken from UniProtKB at the EBI.


Organism:		Saccharomyces cerevisiae (strain ATCC 204508 / S288c) (Baker's yeast).
Taxonomy:		Eukaryota; Fungi; Dikarya; Ascomycota; Saccharomycotina; Saccharomycetes; Saccharomycetales; Saccharomycetaceae; Saccharomyces.



Function:		Lipid transporter involved in lipid countertransport between the Golgi complex and membranes of the endoplasmic reticulum: specifically exchanges sterol with phosphatidylinositol 4-phosphate (PI4P), delivering sterol to the Golgi in exchange for PI4P, which is degraded by the SAC1 phosphatase in the endoplasmic reticulum (PubMed:16136145, PubMed:22162133). Displays a similar affinity for PI4P and sterols (PubMed:22162133). Binds sterol and PI4P in a mutually exclusive manner (Probable). {ECO:0000269\|PubMed:16136145, ECO:0000269\|PubMed:22162133, ECO:0000305}.


Subcellular location:		Golgi apparatus membrane {ECO:0000269\|PubMed:11916983}.
Domain:		Consists of a beta-barrel forming a sterol-binding pocket. When empty, the N-terminal lid (29 residues) is unfolded and leaves the pocket open. Upon sterol binding, this segment forms a lid that blocks the sterol molecule in the pocket (PubMed:16136145). Phosphatidylinositol 4-phosphate (PI4P) binding sites are roughly the same as for sterol. First, the sterol-binding pocket accommodates the PI4P acyl chains. Second, a shallow pocket at the entrance of the tunnel, which contains critical residues such as Lys-336, His-143 and His-144, selects the polar head of PI4P with high specificity. This interaction is probably essential for compensating loose binding of the PI4P acyl chains. Third, the N-terminal lid secures the bound PI4P molecule by wrapping its glycerol moiety (PubMed:22162133). {ECO:0000269\|PubMed:16136145, ECO:0000269\|PubMed:22162133}.
Miscellaneous:		Present with 32200 molecules/cell in log phase SD medium. {ECO:0000269\|PubMed:14562106}.
Similarity:		Belongs to the OSBP family. {ECO:0000305}.