Eukaryotic translation initiation factor 3 subunit J (EIF3J)
The protein contains 258 amino acids for an estimated molecular weight of 29062 Da.
Component of the eukaryotic translation initiation factor 3 (eIF-3) complex, which is required for several steps in the initiation of protein synthesis (PubMed:25849773, PubMed:27462815). The eIF-3 complex associates with the 40S ribosome and facilitates the recruitment of eIF-1, eIF-1A, eIF-2:GTP:methionyl-tRNAi and eIF-5 to form the 43S pre-initiation complex (43S PIC). The eIF-3 complex stimulates mRNA recruitment to the 43S PIC and scanning of the mRNA for AUG recognition. The eIF-3 complex is also required for disassembly and recycling of post-termination ribosomal complexes and subsequently prevents premature joining of the 40S and 60S ribosomal subunits prior to initiation. The eIF-3 complex specifically targets and initiates translation of a subset of mRNAs involved in cell proliferation, including cell cycling, differentiation and apoptosis, and uses different modes of RNA stem-loop binding to exert either translational activation or repression (PubMed:25849773). (updated: Nov. 22, 2017)
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.
- 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.
- 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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| Variant | Description |
|---|---|
| dbSNP:rs2303578 |
Biological Process
Cellular protein metabolic process
Cytoplasmic translation
Formation of cytoplasmic translation initiation complex
Formation of translation preinitiation complex
Gene expression
Regulation of translational initiation
Translation
Translational initiation
The reference OMIM entry for this protein is 603910
Eukaryotic translation initiation factor 3, subunit j; eif3j
Eif3-p35
Eif3-alpha
Eukaryotic translation initiation factor 3, subunit 1, formerly; eif3s1, formerly
DESCRIPTION
Eukaryotic initiation factor-3 (EIF3) has a molecular mass of about 600 kD and contains 13 nonidentical protein subunits, including EIF3J. EIF3 plays a central role in binding of initiator methionyl-tRNA and mRNA to the 40S ribosomal subunit to form the 40S initiation complex (Fraser et al., 2004; Fraser et al., 2007).CLONING
By searching an EST database with partial protein sequences of the human eIF3-p35 and eIF3-p44 (EIF3G; 603913) subunits, Block et al. (1998) isolated cDNAs encoding p35 and p44. The predicted p35 protein contains 258 amino acids. Both p44 and p35 coimmunoprecipitated with p170, indicating that they are components of the eIF3 complex. Northern blot analysis revealed that p35 is expressed as an approximately 2.4-kb mRNA in HeLa cells.GENE FUNCTION
Using insect cells to express EIF3 subunits and an in vitro binding assay, Fraser et al. (2004) identified EIF3J as the EIF3 component required for stable 40S binding. EIF3J promoted binding of a core subcomplex made up of EIF3B (603917), EIF3G, and EIF3I (603911). Purified EIF3 lacking EIF3J bound 40S ribosomal subunits weakly, but it bound tightly when EIF3J was added. Cleavage of a 16-residue C-terminal peptide from EIF3J by caspase-3 (CASP3; 600636) reduced its affinity for the 40S ribosomal subunit, and the cleaved form provided substantially less stabilization of purified EIF3-40S complexes. Fraser et al. (2007) found that EIF3J bound directly to the mRNA entry channel and aminoacyl site of the 40S subunit, placing EIF3J directly in the ribosomal decoding center. EIF3J also interacted with EIF3A (602039) and reduced 40S subunit affinity for mRNA. High affinity for mRNA was restored upon recruitment of initiator tRNA, even though EIF3J remained in the mRNA-binding cleft in the presence of tRNA. Fraser et al. (2007) concluded that EIF3J governs the binding of initiation factors and mRNA to form the initiation complex.BIOCHEMICAL FEATURES
- Crystal Structure Hashem et al. (2013) presented a cryoelectron microscopy reconstruction of a 40S ribosomal complex containing EIF3 and the classical swine fever virus (CSFV) internal ribosome entry sites (IRES). Although the position and interactions of the CSFV IRES with the 40S subunit in this complex are similar to those of the hepatitis C virus (HCV) IRES in the 40S-IRES binary complex, EIF3 is completely displaced from its ribosomal position in the 43S complex, and instead interacts through its ribosome-binding surface exclusively with the apical region of domain III of the IRES. Hashem et al. (2013) concluded that their results suggested a role for the specific interaction of HCV-like IRESs with EIF3 in preventing ribosomal association of EIF3, which could serve 2 purposes: relieving the competition between the IRES and EIF3 for a common binding site on the 40S subunit, and reducing formation of 43S complexes, thereby favoring translation of viral mRNAs. ... More on the omim web site
May 12, 2019: Protein entry updated
Automatic update: model status changed
Nov. 17, 2018: Protein entry updated
Automatic update: model status changed
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
Oct. 27, 2017: Protein entry updated
Automatic update: model status changed
March 16, 2016: Protein entry updated
Automatic update: OMIM entry 603910 was added.
Jan. 24, 2016: Protein entry updated
Automatic update: model status changed