{"product_id":"recombinant-hepatitis-b-virus-genotype-d-subtype-ayw-protein-x-x-bhp10507655","title":"Recombinant Hepatitis B virus genotype D subtype ayw Protein X (X)","description":"\u003ch2\u003eOverview\u003c\/h2\u003e\u003cp\u003eThis Recombinant Protein provides recombinant \u003cstrong\u003eX\u003c\/strong\u003e from Hepatitis B virus genotype D subtype ayw (isolate Japan\/JYW796\/1988) (HBV-D), produced in E.coli (region 1-154aa). It is commonly used as a defined reagent for assay development, binding studies, and mechanistic research (RUO).\u003c\/p\u003e\u003ch2\u003eKey elements and design rationale\u003c\/h2\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eRegion:\u003c\/strong\u003e 1-154aa (domain boundaries can affect binding\/activity readouts).\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eExpression host:\u003c\/strong\u003e E.coli (may differ from native PTMs\/processing).\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eTag(s):\u003c\/strong\u003e His (supports purification\/detection; consider tag effects in controls).\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch2\u003eBiological background\u003c\/h2\u003e\u003cp\u003eAlso reported as HBx (Peptide X) (pX). Multifunctional protein that plays a role in silencing host antiviral defenses and promoting viral transcription. Does not seem to be essential for HBV infection. May be directly involved in development of cirrhosis and liver cancer. Most of cytosolic activities involve modulation of cytosolic calcium. The effect on apoptosis is controversial depending on the cell types in which the studies have been conducted. May induce apoptosis by localizing in mitochondria and causing loss of mitochondrial membrane potential. May also modulate apoptosis by binding host CFLAR, a key regulator of the death-inducing signaling complex. Promotes viral transcription by using the host E3 ubiquitin ligase DDB1 to target the SMC5-SMC6 complex to proteasomal degradation. This host complex would otherwise bind to viral episomal DNA, and prevents its transcription. Moderately stimulates transcription of many different viral and cellular transcription elements. Promoters and enhancers stimulated by HBx contain DNA binding sites for NF-kappa-B, AP-1, AP-2, c-EBP, ATF\/CREB, or the calcium-activated factor NF-AT.\u003c\/p\u003e\u003ch2\u003eResearch relevance and current trends\u003c\/h2\u003e\u003cul\u003e\n\u003cli\u003eActivity assay development for kinetics, substrate scope, and inhibitor\/activator profiling.\u003c\/li\u003e\n\u003cli\u003eUse of recombinant standards to improve assay calibration and cross-study comparability.\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003eMultifunctional protein that plays a role in silencing host antiviral defenses and promoting viral transcription. Does not seem to be essential for HBV infection. May be directly involved in development of cirrhosis and liver cancer. Most of cytosolic activities involve modulation of cytosolic calcium. The effect on apoptosis is controversial depending on the cell types in which the studies have been conducted. May induce apoptosis by localizing in mitochondria and causing loss of mitochondrial membrane potential. May also modulate apoptosis by binding host CFLAR, a key regulator of the death-inducing signaling complex. Promotes viral transcription by using the host E3 ubiquitin ligase DDB1 to target the SMC5-SMC6 complex to proteasomal degradation. This host complex would otherwise bind to viral episomal DNA, and prevents its transcription. Moderately stimulates transcription of many different viral and cellular transcription elements. Promoters and enhancers stimulated by HBx contain DNA binding sites for NF-kappa-B, AP-1, AP-2, c-EBP, ATF\/CREB, or the calcium-activated factor NF-AT.\u003c\/p\u003e\u003ch2\u003eCommon research applications\u003c\/h2\u003e\u003cul\u003e\n\u003cli\u003eStandard curve or spike-in reference for quantitative assays involving X\u003c\/li\u003e\n\u003cli\u003eEnzymatic activity measurements with defined substrates\/cofactors (assay-dependent)\u003c\/li\u003e\n\u003cli\u003eCompound screening using concentration–response concepts (assay-dependent)\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch2\u003eNotes for experimental interpretation\u003c\/h2\u003e\u003cul\u003e\n\u003cli\u003eRecombinant constructs may not capture all native isoforms or PTMs.\u003c\/li\u003e\n\u003cli\u003eConsider tag- or host-related effects when interpreting binding or activity.\u003c\/li\u003e\n\u003cli\u003eUse appropriate blanks and matrix\/control concepts to separate signal from background.\u003c\/li\u003e\n\u003c\/ul\u003e\u003c!-- Sources (internal): - UniProtKB Q9QMI3 — UniProt — https:\/\/www.uniprot.org\/uniprotkb\/Q9QMI3 - NCBI Gene search: X — NCBI — https:\/\/www.ncbi.nlm.nih.gov\/gene\/?term=X - Ensembl search: X — Ensembl — https:\/\/www.ensembl.org\/Multi\/Search\/Results?q=X - Reactome Pathway Browser — Reactome — https:\/\/reactome.org\/ - NCBI Bookshelf — NCBI — https:\/\/www.ncbi.nlm.nih.gov\/books\/ --\u003e","brand":"CUSABIO TECHNOLOGY LLC","offers":[{"title":"1 mg","offer_id":53053420306797,"sku":"CSB-EP865559HEOb0-1MG","price":2466.0,"currency_code":"USD","in_stock":true},{"title":"100 ug","offer_id":53053560684909,"sku":"CSB-EP865559HEOb0-100UG","price":729.0,"currency_code":"USD","in_stock":true},{"title":"20 ug","offer_id":53053560717677,"sku":"CSB-EP865559HEOb0-20UG","price":388.0,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0949\/7424\/7277\/files\/CSB-EP865559HEOb0-SDS.jpg?v=1772177693","url":"https:\/\/www.ebiohippo.com\/products\/recombinant-hepatitis-b-virus-genotype-d-subtype-ayw-protein-x-x-bhp10507655","provider":"BioHippo","version":"1.0","type":"link"}