Transcriptional activator protein Pur-beta (PURB)
The protein contains 312 amino acids for an estimated molecular weight of 33241 Da.
Has capacity to bind repeated elements in single-stranded DNA such as the purine-rich single strand of the PUR element located upstream of the MYC gene. Plays a role in the control of vascular smooth muscle (VSM) alpha-actin gene transcription as repressor in myoblasts and fibroblasts. Participates in transcriptional and translational regulation of alpha-MHC expression in cardiac myocytes by binding to the purine-rich negative regulatory (PNR) element. Modulates constitutive liver galectin-3 gene transcription by binding to its promoter. May play a role in the dendritic transport of a subset of mRNAs (By similarity). (updated: April 1, 2015)
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.
- 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.
- Wilson and co-workers. (2016) Comparison of the Proteome of Adult and Cord Erythroid Cells, and Changes in the Proteome Following Reticulocyte Maturation. Mol Cell Proteomics. 15(6), 1938-1946.
- Bryk and co-workers. (2017) Quantitative Analysis of Human Red Blood Cell Proteome. J Proteome Res. 16(8), 2752-2761.
- 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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No binding partner found
Biological Process
Cell differentiation
Cell population proliferation
Negative regulation of transcription by RNA polymerase II
Regulation of myeloid cell differentiation
Regulation of transcription by RNA polymerase II
Transcription, DNA-templated
Molecular Function
DNA-binding transcription factor activity
DNA-binding transcription factor activity, RNA polymerase II-specific
DNA-binding transcription repressor activity, RNA polymerase II-specific
Double-stranded DNA binding
MRNA binding
Poly(A) RNA binding
Purine-rich negative regulatory element binding
RNA binding
RNA polymerase II transcription regulatory region sequence-specific DNA binding
Sequence-specific DNA binding
Single-stranded DNA binding
SMAD binding
Transcription factor binding
The reference OMIM entry for this protein is 608887
Purine-rich element-binding protein b; purb
Pur-beta
CLONING
By probing a HeLa cell cDNA library with a fragment of the PURA (600473) sequence, Bergemann et al. (1992) identified a partial sequence of a homologous cDNA, designated PURB, encoding a protein with a 23-amino acid class I motif and an amphipathic helix similar to those found in PURA. Kelm et al. (1997) cloned mouse Purb (p44) and Pura (p46) and identified them as the 2 components of the previously designated vascular actin single-stranded DNA-binding factor-2, which specifically bound to purine-rich regions within an enhancer and an exon of vascular actin (Kelm et al., 1996). Like Pura, the deduced 324-amino acid Purb protein contains class I and class II repeats and a 23-amino acid PSYC motif that is homologous to the Rb-binding region of SV-40 large T antigen. Purb differs from Pura in that the second class II repeat is interrupted by a glycine-rich region, the N-terminal glycine-rich region is interrupted by a 6-amino acid region, and there is no glutamine-rich C-terminal region. ... More on the omim web site
Feb. 2, 2018: Protein entry updated
Automatic update: Uniprot description updated
Dec. 19, 2017: Protein entry updated
Automatic update: Uniprot description updated
March 25, 2017: Additional information
No protein expression data in P. Mayeux work for PURB
March 16, 2016: Protein entry updated
Automatic update: OMIM entry 608887 was added.