Oxysterol-binding protein-related protein 8 (OSBPL8)
The protein contains 889 amino acids for an estimated molecular weight of 101196 Da.
Lipid transporter involved in lipid countertransport between the endoplasmic reticulum and the plasma membrane: specifically exchanges phosphatidylserine with phosphatidylinositol 4-phosphate (PI4P), delivering phosphatidylserine to the plasma membrane in exchange for PI4P, which is degraded by the SAC1/SACM1L phosphatase in the endoplasmic reticulum. Binds phosphatidylserine and PI4P in a mutually exclusive manner (PubMed:26206935). Binds oxysterol, 25-hydroxycholesterol and cholesterol (PubMed:17428193, PubMed:17991739, PubMed:21698267). (updated: Jan. 31, 2018)
Protein identification was indicated in the following studies:
- Goodman and co-workers. (2013) The proteomics and interactomics of human erythrocytes. Exp Biol Med (Maywood) 238(5), 509-518.
- Lange and co-workers. (2014) Annotating N termini for the human proteome project: N termini and Nα-acetylation status differentiate stable cleaved protein species from degradation remnants in the human erythrocyte proteome. J Proteome Res. 13(4), 2028-2044.
- Hegedűs and co-workers. (2015) Inconsistencies in the red blood cell membrane proteome analysis: generation of a database for research and diagnostic applications. Database (Oxford) 1-8.
- Bryk and co-workers. (2017) Quantitative Analysis of Human Red Blood Cell Proteome. J Proteome Res. 16(8), 2752-2761.
- D'Alessandro and co-workers. (2017) Red blood cell proteomics update: is there more to discover? Blood Transfus. 15(2), 182-187.
- Chu and co-workers. (2018) Quantitative mass spectrometry of human reticulocytes reveal proteome-wide modifications during maturation. Br J Haematol. 180(1), 118-133.
Methods
The following articles were analysed to gather the proteome content of erythrocytes.
The gene or protein list provided in the studies were processed using the ID mapping API of Uniprot in September 2018. The number of proteins identified and mapped without ambiguity in these studies is indicated below.
Only Swiss-Prot entries (reviewed) were considered for protein evidence assignation.
| Publication | Identification 1 | Uniprot mapping 2 | Not mapped / Obsolete | TrEMBL | Swiss-Prot |
|---|---|---|---|---|---|
| Goodman (2013) | 2289 (gene list) | 2278 | 53 | 20599 | 2269 |
| Lange (2014) | 1234 | 1234 | 7 | 28 | 1224 |
| Hegedus (2015) | 2638 | 2622 | 0 | 235 | 2387 |
| Wilson (2016) | 1658 | 1528 | 170 | 291 | 1068 |
| d'Alessandro (2017) | 1826 | 1817 | 2 | 0 | 1815 |
| Bryk (2017) | 2090 | 2060 | 10 | 108 | 1942 |
| Chu (2018) | 1853 | 1804 | 55 | 362 | 1387 |
1 as available in the article and/or in supplementary material
2 uniprot mapping returns all protein isoforms as one entry
The compilation of older studies can be retrieved from the Red Blood Cell Collection database.
The data and differentiation stages presented below come from the proteomic study and analysis performed by our partners of the GReX consortium, more details are available in their published work.
This protein is predicted to be membranous by TOPCONS.
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No binding partner found
Biological Process
Activation of protein kinase B activity
Fat cell differentiation
Lipid transport
Negative regulation of cell migration
Negative regulation of sequestering of triglyceride
Obsolete positive regulation of glucose import in response to insulin stimulus
Phosphatidylserine acyl-chain remodeling
Phospholipid transport
Positive regulation of glucose import
Positive regulation of insulin receptor signaling pathway
Positive regulation of protein kinase B signaling
Protein localization to nuclear pore
The reference OMIM entry for this protein is 606736
Oxysterol-binding protein-like protein 8; osbpl8
Osbp-related protein 8; orp8
Kiaa1451
DESCRIPTION
OSBPL8 is a member of the OSBP family of intracellular lipid receptors. For background information on OSBPs, see OSBP2 (606729).CLONING
By screening for cDNAs with the potential to encode large proteins expressed in brain, Nagase et al. (2000) identified a cDNA encoding OSBPL8, which they called KIAA1451. The deduced 488-amino acid protein was predicted to be 33% identical to mouse Osbp. RT-PCR analysis detected wide expression that was strongest in testis, ovary, liver, kidney, and brain. Within brain, expression was particularly strong in caudate nucleus. Lehto et al. (2001) used RT-PCR analysis with specific primers and 5-prime RACE to isolate a full-length cDNA encoding OSBPL8, which they called ORP8. Sequence analysis predicted that the 847-amino acid protein contains a C-terminal sterol-binding (SB) domain of approximately 400 residues that includes the OSBP motif (EQVSHHPP). It has a pleckstrin homology (PH) domain in its N terminus. OSBPL8 is 78% and 88% identical to OSBPL5 (606733) in the SB and PH domains, respectively. Jaworski et al. (2001) cloned multiple OSBPs, including 2 variants of OSBPL8 that encode proteins of 847 and 889 amino acids. RT-PCR analysis detected ubiquitous expression that was strongest in brain, testis, and fetal brain.GENE STRUCTURE
By sequence analysis, Lehto et al. (2001) determined that the OSBPL8 gene contains 23 exons. Jaworski et al. (2001) also found that it contains 23 exons.MAPPING
By radiation hybrid analysis, Nagase et al. (2000) mapped the OSBPL8 gene to chromosome 12. By sequence analysis, Lehto et al. (2001) also mapped the gene to chromosome 12. Jaworski et al. (2001) localized the gene to 12p. ... More on the omim web site
Feb. 10, 2018: Protein entry updated
Automatic update: Entry updated from uniprot information.
Feb. 2, 2018: Protein entry updated
Automatic update: Uniprot description updated
Dec. 19, 2017: Protein entry updated
Automatic update: Uniprot description updated
Nov. 23, 2017: Protein entry updated
Automatic update: Uniprot description updated
March 16, 2016: Protein entry updated
Automatic update: OMIM entry 606736 was added.
Feb. 24, 2016: Protein entry updated
Automatic update: model status changed