Antibody News

Atg12 is a ubiquitin-like protein that plays an essential role in cellular homeostasis by regulating the degradation and recycling of cytoplasmic organelles and macromolecules. Atg12 is one of two ubiquitin-like protein systems that is required during the early steps of autophagosome formation. Upon the initiation of phagopore assembly Atg12 is activated by binding to the E1-like enzyme Atg7 and is then transferred to the E2 enzyme Atg10. Finally, Atg12 is conjugated to a lysine residue in Atg5 allowing the formation of a large multimeric complex with Atg16. This Atg12-Atg5-Atg16 complex localizes to the surface of the expanding phagopore where it functions as an E3 ligase for the lipidation of Atg8, the other autophagy-specific ubiquitin-like protein. Atg8, or LC3 in mammals, is conjugated to the lipid phosphatidylethanolamine and is...

Mucin 1 (Muc1) is a heavily glycosylated protein that coats mucosal epithelial cells of the lungs, intestines, and other organs. Muc1 is thought to protect cells by binding to pathogens and responding to infections. During trafficking to the plasma membrane Muc1 is proteolytically cleaved in the endoplasmic reticulum to form a stable heterodimeric complex of two fragments. The smaller C-terminal region contains the cytoplasmic tail and transmembrane domain and is non-covalently bound to the larger glycosylated extracellular domain. Further cleavage or processing of the extracellular domain can cause release or shedding into the extracellular space and is thought to be involved in protein turnover and degradation or could potentially trigger a signaling response in the cytoplasmic domain. Muc1 is highly overexpressed in breast, ovarian, and prostate cancers and is correlated with metastasis and poor survival. Overexpressed Muc1 localizes throughout the cell in these...

Heterogeneous nuclear ribonucleoprotein A1 (hnRNP A1) is an abundant ubiquitously expressed protein with important roles in the regulation of gene expression. hnRNP A1 is involved in transcription as well as the splicing, trafficking, and translation of RNA transcripts. hnRNP A1 binds RNA targets in a sequence specific manner through two N-terminal RNA recognition motifs (RRM) and a C-terminal RGG box RNA binding domain. During transcription hnRNPA1 binds to the promoter of target genes and has been shown to function as both a transcriptional activator and repressor. During the removal of introns hnRNP A1 is present in various splicing complexes and interacts with the essential splicing factor U2AF. hnRNP A1 also contributes to alternative splicing by modulating splice site selection. Once in the cytoplasm hnRNPA1 associates with internal ribosomal entry sites (IRES) of mature mRNA and can both inhibitor enhance translation depending on the...

B-cell lymphoma 2 (Bcl-2) protein is an oncogene that normally acts as an apoptotic inhibitor and localizes to the mitochondrial membrane where it prevents the release of cytochrome c. The Bcl-2 protein family consists of over 20 proteins each containing at least one Bcl-2 homology (BH) domains and have either proapoptic or antiapoptotic activities. During induction of apoptosis the oligomerization of the Bcl-2 family proteins Bax and Bak forms a pore in the mitochondrial membrane triggering the release of cytochrome c. While it is still unclear, Bcl-2 is thought to directly bind and sequester BH-3 domain proapoptotic proteins such as BIM or BID. Upon release, BIM or BID are free to bind and activate Bax/Bak to induce cell death. Bcl-2 is often overexpressed in tumor cells where it can enhance cell survival despite the presence of apoptotic...

Atg9 is the only essential transmembrane protein involved in cellular autophagy. Autophagy regulates cellular homeostasis by allowing the turnover and recycling of misfolded proteins and damaged organelles. Formation of the double-membrane isolation membrane that forms the pre-autophagosome requires the contribution of highly mobile cytoplasmic vesicles containing Atg9. These vesicles are derived from recycling endosomes and are responsible for recruiting and delivering lipid components to the assembling autophagosome. Given this essential role in autophagosome assembly Atg9 is an excellent marker for the induction of autophagy and tracking membrane sources for formation of the autophagosome. In vertebrates Atg9 exists in two different isoforms: Atg9a and Atg9b. Atg9a is ubiquitously expressed while Atg9b is enriched in the placenta and the pituitary (1) and is induced by hypoxic conditions (2). Both proteins show similar localization in...

Hypoxia-inducible factor 1 (HIF-1) allows cells to respond to changing levels of oxygen in the environment. HIF-1 is a heterodimeric transcription factor consisting of alpha and beta subunits. Under normal conditions HIF-1 alpha is continuously synthesized and degraded. HIF-1 alpha degradation is mediated through an oxygen-dependent degradation domain that is hydroxylated and leads to ubiquitylation and proteolysis. HIF-1 beta on the other hand is constitutively expressed and localizes to the nucleus. Under hypoxic conditions HIF-1alpha is stabilized and translocates to the nucleus where it dimerizes with HIF-1 beta. There it binds to hypoxia response elements (HRE) in the promoters of target genes involved in angiogenesis and cell proliferation including vascular endothelial growth factor (VEGF) and erythropoietin.  HIF-1 alpha also helps regulate cell metabolism under hypoxic conditions by controlling the...

Survivin is an anti-apoptotic protein which is the smallest protein within a large family of proteins including X-linked IAP, c-IAP1 and 2, IAP-like protein-2, melanoma IAP, NAIP, and Livin. Survivin is responsible for a wide range of basic cellular functions that include the cell cycle regulation, fetal development, cell migration, and tumor progression. Xu et al from the MD Anderson Cancer Center used the survivin antibody to untangle apoptotic pathway components in promyelocytic leukemia by generating a comprehensive DNA microarray profile of target genes (1). Their detailed experiments allowed them to identify a novel PML4-dependent mechanism that ultimately downregulates survivin.

Western Blot: Survivin...

The Beclin 1 protein is a central regulator of autophagy in mammalian cells. Autophagy is an essential process used to maintain cellular homeostasis by degrading and recycling cellular components such as damaged or worn out organelles and macromolecules. Autophagy is also activated in response to cellular stresses such as nutrient starvation or intracellular pathogens and can protect the cell from programmed cell death. Beclin 1 acts during the initiation stage of autophagy by forming the isolation membrane, a double-membrane structure that engulfs cytoplasmic material to form the autophagosome. Beclin 1 contains three structural domains: a BH-3 only domain, a central coiled-coil domain (CCD), and an evolutionarily conserved domain (ECD). These domains interact with a network of proteins involved in the regulation of autophagy. Under normal conditions the anti-apoptotic protein Bcl-2 inhibits autophagy...

The ATF6 endoplasmic reticulum (ER) stress-regulated transcription factor is constitutively expressed and plays a central role in the mammalian unfolded protein response (UPR). This fundamental pathway is responsible for balancing cellular homeostasis under stressful conditions resulting from environmental or physiological perturbations. The ATF6 molecule is anchored in the endoplasmic reticulum (ER) membrane when in its inactive form. Under conditions when a conversion to the ATF6 active form is required, ATF6 translocates to the Golgi and is cleaved by the S1P and S2P proteases. This intramembrane proteolytic event enables the translocation of the activated, N-terminal ATF6 component to the nucleus, where it continues the downstream cascade by binding to ER stress-response elements within ER stress-response genes (ERSRGs).

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ATG9A is the only essential integral membrane protein involved in autophagy. ATG9A contains six transmembrane domains and initiates the assembly of autophagosomes. The autophagosome is a double-membrane structure that engulfs and eventually degrades cytoplasmic materials such as organelles or macromolecules. Assembly of the autophagosome requires the delivery of lipids and membrane components to initiate and expand the double-membrane pre-autophagosome structure called the isolation membrane. ATG9A localizes to highly mobile cytoplasmic vesicles which are thought to play a key role in recruiting and delivering membrane and lipids to the assembling autophagosome. Interestingly ATG9A localizes only to the outer membrane layer of the double-membrane pre-autophagosome structure. This essential role in autophagosome assembly makes ATG9A an excellent marker for autophagy induction and for examining the membrane dynamics of early autophagosome...

Read our list of eight facts people in a lab will understand including: pipetting counts as thumb cardio, a watched frozen trypsin bottle never thaws, dark bags under your eyes are evidence your experiment needs more optimization,  700 post-it notes are just as good as a lab notebook and more. Do you have a fact that wasn’t included in the list? Submit it in the comments section below and we will add it to our next list.

IL-1 was originally identified and cloned as a lymphocyte mitogen and much later, was found to be comprised of two closely related but distinct proteins, interleukin 1 alpha (IL-1 alpha) and interleukin 1 beta (IL-1 beta). Both these proteins bind to the same cell surface receptor. IL-1 is primarily released from stimulated macrophages, but is also released from several other cell types. Along with other IL-1 gene family members, IL-1 beta falls within a cytokine gene cluster on chromosome 2. It plays a key role in inflammatory and immune cell processes.

Western Blot: IL-1 beta/IL-1F2 Antibody [NB600-633] - analysis of IL-1 beta in Rhesus fetal membrane using anti-IL-1 beta antibody. 

In their 2009 Nature Medicine publication, French researchers...