XBP1 Blocking Peptide | XBP1 (HGNC:12801) blocking peptide

XBP1 Antibody (C-term) Blocking peptide

• Gene Names: XBP1; XBP2; TREB5; XBP-1; TREB-5
• Synonyms: XBP1; XBP1 Antibody (C-term) Blocking peptide; X-box-binding protein 1; XBP-1; Tax-responsive element-binding protein 5; TREB5; XBP2; XBP1 (HGNC:12801) blocking peptide

• Form/Format: Synthetic peptide was lyophilized with 100% acetonitrile and is supplied as a powder. Reconstitute with 0.1 ml DI water for a final concentration of 1 mg/ml.
• Sequence Length: 261

• Cellular Location: Endoplasmic reticulum. Note: Colocalizes with ERN1 and KDR in the endoplasmic reticulum in endothelial cells in a vascular endothelial growth factor (VEGF)-dependent manner. Isoform 2: Nucleus. Cytoplasm. Note: Localizes predominantly in the nucleus. Colocalizes in the nucleus with SIRT1. Translocates into the nucleus in a PIK3R-, ER stress- induced- and/or insulin-dependent manner (By similarity)
• Tissue Location: Expressed in plasma cells in rheumatoid synovium (PubMed:11460154). Over-expressed in primary breast cancer and metastatic breast cancer cells (PubMed:25280941) Isoform 1 and isoform 2 are expressed at higher level in proliferating as compared to confluent quiescent endothelial cells (PubMed:19416856).
• Preparation and Storage: Maintain refrigerated at 2-8 degree C for up to 6 months. For long term storage store at -20 degree C.

Related Product Information for XBP1 (HGNC:12801) blocking peptide

Functions as a transcription factor during endoplasmic reticulum (ER) stress by regulating the unfolded protein response (UPR). Required for cardiac myogenesis and hepatogenesis during embryonic development, and the development of secretory tissues such as exocrine pancreas and salivary gland (By similarity). Involved in terminal differentiation of B lymphocytes to plasma cells and production of immunoglobulins (PubMed:11460154). Modulates the cellular response to ER stress in a PIK3R-dependent manner (PubMed:20348923). Binds to the cis-acting X box present in the promoter regions of major histocompatibility complex class II genes (PubMed:8349596). Involved in VEGF-induced endothelial cell (EC) proliferation and retinal blood vessel formation during embryonic development but also for angiogenesis in adult tissues under ischemic conditions. Functions also as a major regulator of the UPR in obesity-induced insulin resistance and type 2 diabetes for the management of obesity and diabetes prevention (By similarity).

NCBI and Uniprot Product Information

• NCBI GI #: 60416406
• NCBI GeneID: 7494
• UniProt Accession #: P17861; Q8WYK6; Q969P1; Q96BD7
• Molecular Weight: 40,148 Da
• NCBI Official Full Name: X-box-binding protein 1
• NCBI Official Synonym Full Names: X-box binding protein 1
• NCBI Official Symbol: XBP1
• NCBI Official Synonym Symbols: XBP2; TREB5; XBP-1; TREB-5
• NCBI Protein Information: X-box-binding protein 1
• UniProt Protein Name: X-box-binding protein 1
• UniProt Gene Name: XBP1
• UniProt Synonym Gene Names: TREB-5
• UniProt Entry Name: XBP1_HUMAN

NCBI Description

This gene encodes a transcription factor that regulates MHC class II genes by binding to a promoter element referred to as an X box. This gene product is a bZIP protein, which was also identified as a cellular transcription factor that binds to an enhancer in the promoter of the T cell leukemia virus type 1 promoter. It may increase expression of viral proteins by acting as the DNA binding partner of a viral transactivator. It has been found that upon accumulation of unfolded proteins in the endoplasmic reticulum (ER), the mRNA of this gene is processed to an active form by an unconventional splicing mechanism that is mediated by the endonuclease inositol-requiring enzyme 1 (IRE1). The resulting loss of 26 nt from the spliced mRNA causes a frame-shift and an isoform XBP1(S), which is the functionally active transcription factor. The isoform encoded by the unspliced mRNA, XBP1(U), is constitutively expressed, and thought to function as a negative feedback regulator of XBP1(S), which shuts off transcription of target genes during the recovery phase of ER stress. A pseudogene of XBP1 has been identified and localized to chromosome 5. [provided by RefSeq, Jul 2008]

Uniprot Description

XBP1: a transcription factor essential for hepatocyte growth, the differentiation of plasma cells, immunoglobulin secretion, and the unfolded protein response (UPR). XBP1 mRNA is spliced by IRE1 during the UPR to generate a new C-terminus, converting it into a potent unfolded-protein response transcriptional activator and triggering growth arrest and apoptosis. Only the spliced form of XBP1 can activate the UPR efficiently. Activates UPR target genes via direct binding to the UPR element (UPRE). Binds DNA preferably to the CRE-like element 5'-GATGACGTG[TG]N(3)[AT]T-3', and also to some TPA response elements (TRE). Binds to the HLA DR-alpha promoter. Binds to the Tax-responsive element (TRE) of HTLV-I. Up-regulated by ATF6 via direct binding to the ERSE in response to endoplasmic reticulum stress. Genetic variations in XBP1 could be associated with susceptibility to major affective disorder type 7 (MAFD7). Major affective disorders represent a class of mental disorders characterized by a disturbance in mood as their predominant feature. Two human isoforms are produced by alternative splicing. Isoform 1 is also known as XBP-1U. Isoform 2, also known as XBP-1S, is produced by IRE1 in response to endoplasmic reticulum stress. IRE1 cleaves a 26-bp fragment causing a frameshift of the mRNA transcript.

Protein type: Transcription factor; DNA-binding

Chromosomal Location of Human Ortholog: 22q12.1|22q12

Cellular Component: cytoplasm; endoplasmic reticulum; nucleoplasm; nucleus

Molecular Function: DNA binding; protein binding; protein heterodimerization activity; transcription factor activity

Biological Process: angiogenesis; cellular response to glucose starvation; cellular response to insulin stimulus; cellular response to nutrient; cholesterol homeostasis; fatty acid biosynthetic process; fatty acid homeostasis; immune response; liver development; negative regulation of apoptosis; neuron development; positive regulation of B cell differentiation; positive regulation of fat cell differentiation; positive regulation of immunoglobulin production; positive regulation of immunoglobulin secretion; positive regulation of MHC class II biosynthetic process; positive regulation of T cell differentiation; positive regulation of transcription from RNA polymerase II promoter; positive regulation of transcription of target genes involved in unfolded protein response; sterol homeostasis; transcription from RNA polymerase II promoter; ubiquitin-dependent protein catabolic process; unfolded protein response

Disease: Major Affective Disorder 7