Human Gene P4HB (ENST00000331483.9) Description and Page Index
Description: Homo sapiens prolyl 4-hydroxylase subunit beta (P4HB), mRNA. (from RefSeq NM_000918) RefSeq Summary (NM_000918): This gene encodes the beta subunit of prolyl 4-hydroxylase, a highly abundant multifunctional enzyme that belongs to the protein disulfide isomerase family. When present as a tetramer consisting of two alpha and two beta subunits, this enzyme is involved in hydroxylation of prolyl residues in preprocollagen. This enzyme is also a disulfide isomerase containing two thioredoxin domains that catalyze the formation, breakage and rearrangement of disulfide bonds. Other known functions include its ability to act as a chaperone that inhibits aggregation of misfolded proteins in a concentration-dependent manner, its ability to bind thyroid hormone, its role in both the influx and efflux of S-nitrosothiol-bound nitric oxide, and its function as a subunit of the microsomal triglyceride transfer protein complex. [provided by RefSeq, Jul 2008]. Publication Note: This RefSeq record includes a subset of the publications that are available for this gene. Please see the Gene record to access additional publications. ##Evidence-Data-START## Transcript exon combination :: SRR1803611.5600.1, HM005572.1 [ECO:0000332] RNAseq introns :: single sample supports all introns SAMEA1968540, SAMEA1968832 [ECO:0000348] ##Evidence-Data-END## ##RefSeq-Attributes-START## MANE Ensembl match :: ENST00000331483.9/ ENSP00000327801.4 RefSeq Select criteria :: based on conservation, expression ##RefSeq-Attributes-END## Gencode Transcript: ENST00000331483.9 Gencode Gene: ENSG00000185624.15 Transcript (Including UTRs) Position: hg38 chr17:81,843,166-81,860,535 Size: 17,370 Total Exon Count: 11 Strand: - Coding Region Position: hg38 chr17:81,844,012-81,860,471 Size: 16,460 Coding Exon Count: 11
ID:PDIA1_HUMAN DESCRIPTION: RecName: Full=Protein disulfide-isomerase; Short=PDI; EC=22.214.171.124; AltName: Full=Cellular thyroid hormone-binding protein; AltName: Full=Prolyl 4-hydroxylase subunit beta; AltName: Full=p55; Flags: Precursor; FUNCTION: This multifunctional protein catalyzes the formation, breakage and rearrangement of disulfide bonds. At the cell surface, seems to act as a reductase that cleaves disulfide bonds of proteins attached to the cell. May therefore cause structural modifications of exofacial proteins. Inside the cell, seems to form/rearrange disulfide bonds of nascent proteins. At high concentrations, functions as a chaperone that inhibits aggregation of misfolded proteins. At low concentrations, facilitates aggregation (anti-chaperone activity). May be involved with other chaperones in the structural modification of the TG precursor in hormone biogenesis. Also acts a structural subunit of various enzymes such as prolyl 4-hydroxylase and microsomal triacylglycerol transfer protein MTTP. CATALYTIC ACTIVITY: Catalyzes the rearrangement of -S-S- bonds in proteins. SUBUNIT: Homodimer. Monomers and homotetramers may also occur. Also constitutes the structural subunit of prolyl 4-hydroxylase and of the microsomal triacylglycerol transfer protein MTTP in mammalian cells. Stabilizes both enzymes and retain them in the ER without contributing to the catalytic activity (By similarity). Binds UBQLN1. Binds to CD4, and upon HIV-1 binding to the cell membrane, is part of a P4HB/PDI-CD4-CXCR4-gp120 complex. INTERACTION: Q03518:TAP1; NbExp=4; IntAct=EBI-395883, EBI-747259; SUBCELLULAR LOCATION: Endoplasmic reticulum lumen. Melanosome. Cell membrane; Peripheral membrane protein (Potential). Note=Highly abundant. In some cell types, seems to be also secreted or associated with the plasma membrane, where it undergoes constant shedding and replacement from intracellular sources (Probable). Localizes near CD4-enriched regions on lymphoid cell surfaces. Identified by mass spectrometry in melanosome fractions from stage I to stage IV. MISCELLANEOUS: Reduces and may activate fusogenic properties of HIV-1 gp120 surface protein, thereby enabling HIV-1 entry into the cell. SIMILARITY: Belongs to the protein disulfide isomerase family. SIMILARITY: Contains 2 thioredoxin domains.
The RNAfold program from the Vienna RNA Package is used to perform the secondary structure predictions and folding calculations. The estimated folding energy is in kcal/mol. The more negative the energy, the more secondary structure the RNA is likely to have.
ModBase Predicted Comparative 3D Structure on P07237
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Orthologous Genes in Other Species
Orthologies between human, mouse, and rat are computed by taking the best BLASTP hit, and filtering out non-syntenic hits. For more distant species reciprocal-best BLASTP hits are used. Note that the absence of an ortholog in the table below may reflect incomplete annotations in the other species rather than a true absence of the orthologous gene.