Phosphoribosyl pyrophosphate synthase-associated protein 1 (PRPSAP1)
The protein contains 356 amino acids for an estimated molecular weight of 39394 Da.
Seems to play a negative regulatory role in 5-phosphoribose 1-diphosphate synthesis. (updated: Sept. 12, 2018)
Protein identification was indicated in the following studies:
- 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.
- 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.
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The reference OMIM entry for this protein is 601249
Phosphoribosylpyrophosphate synthetase-associated protein 1; prpsap1
Pap39
DESCRIPTION
Phosphoribosylpyrophosphate (PRPP) synthetase (PRPS) catalyzes the formation of PRPP from ATP and ribose 5-phosphate. Ishizuka et al. (1996) noted that the rat liver enzyme exists as complex aggregates of 34-, 39- (603762), and 41-kD components, with the 34-kD species being the catalytic subunit. The 34-kD subunit from rat liver is a mixture of 2 highly homologous isoforms that are encoded by 2 distinct genes, designated PRPS1 (311850) and PRPS2 (311860). The 39- and 41-kD components of these enzymes are termed PRPP synthetase-associated proteins (PAPs).CLONING
Kita et al. (1994) cloned the cDNA for the 39-kD component (PAP39) from rat liver. The deduced amino acid sequence was remarkably similar to those of the 34-kD subunits. Using a PCR strategy with primers based on the sequence of the rat PAP39 protein, Ishizuka et al. (1996) cloned cDNAs encoding human PAP39 (PRPSAP1). The deduced 356-amino acid human protein shares 98% identity with rat PAP39 and 44% identity with the proteins encoded by human PRPS1 and PRPS2. Northern blot analysis revealed that PAP39 was expressed as a 2.2-kb mRNA in all human tissues tested.GENE FUNCTION
Kita et al. (1994) showed that removal of PAPs from the rat liver enzyme complex led to an increase in enzyme activity of the remaining catalytic subunits. The authors proposed that PAPs have a negative regulatory role in PRPP synthesis.MAPPING
Ishizuka et al. (1996) mapped the PRPSAP1 gene to chromosome 17q24-q25 by PCR analysis of somatic cell hybrids and by fluorescence in situ hybridization. ... More on the omim web site
Oct. 20, 2018: Protein entry updated
Automatic update: OMIM entry 601249 was added.
Oct. 19, 2018: Additional information
Initial protein addition to the database. This entry was referenced in Bryk and co-workers. (2017).