Antibody News

The role of TLR4 in breast cancer

Wednesday, June 15, 2016 - 11:40

Toll like receptors (TLRs) are highly conserved proteins that are first known for their role in pathogen recognition and immune response activation.  In order to elicit the necessary immune response in reaction to a foreign pathogen, TLRs trigger cytokine production depending on the behavior patterns of the pathogen itself.  Specifically, TLR4 acts through bacterial lipopolysaccharide (LPS), which composes the outer wall of Gram-negative bacteria.  Bacterial LPS is also a potent activator of the immune system.  Essentially, LPS is a ligand to TLR4, which in turn interacts with myeloid differentiation protein 2 (MD-2), CD14 and LPS-binding protein (LBP), which exist in the extracellular space.  This interaction turns on a signaling cascade that leads to the production of the required cytokines to trigger an effective immune response. 

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Using SCP3/SYCP3 Antibodies as Meiosis Markers in Gametogenesis and DNA Repair Studies

Monday, June 13, 2016 - 11:08

The synaptonemal complex (SC) is a protein structure that forms during the synapsis of homologous chromosomes during meiosis. This structure is involved in the processes of chromosome synapsis, genetic recombination and subsequent chromosome segregation, and is essential for gametogenesis.

The SC is comprised of three component proteins SYCP1, SYCP2, and SYCP3. SYCP1 functions in SC assembly, meiotic recombination, and XY body formation (de Vries et al., 2005). SYCP2 is required for synaptonemal complex assembly and chromosomal synapsis (Yang et al., 2006). Synaptonemal complex protein 3 (SCP3/SYCP3) is an essential structural component of the SC lateral complex (Alsheimer et al., 2010). Mutations in the SYCP3 gene have been linked to azoospermia in males and recurrent pregnancy loss in females (Sazegari et al., 2014), suggesting it plays a critical role in proper gametogenesis.

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Synapsin I, a pre-synaptic marker

Wednesday, June 8, 2016 - 14:40

Synapsin-I, also called Synapsin 1/Syn1, is an ~80 kDa protein (predicted mol. wt. 74.1 kDa) which belongs to the Synapsin family (Synapsin I, Synapsin II, Synapsin III). Synapsins are the evolutionarily conserved phospho-proteins which are associated with the cytosolic side of the synaptic vesicles. They tether the vesicles to the actin cytoskeleton, thus forming a reserve pool. Synapsins I and II are generally found in mature synapses, whereas, Synapsin III is typically expressed in developing synapses with a relatively lower expression. Synapsins represents the most abundant of neuron-specific phospho-proteins, consisting of 9% of the total amount of all vesicle proteins in neurons wherein they play a critical role in the regulation of neurotransmitter release (Greengard et al. 1993)....

The diverse functions of RANKL/TRANCE/TNFSF11

Monday, June 6, 2016 - 11:39

RANKL (also known as TNF-related activation-induced cytokine), or receptor activator of nuclear factor-κB ligand, was first discovered as a key player in the RANKL/RANK/OPG osteoclast formation pathway. Osteoclasts are large multinucleate cells that absorb bone tissue throughout growth and healing cycles.  Osteoclasts express RANKL, which in turn binds to the RANK receptor to regulate osteoclast differentiation.  In healthy bone formation, dynamics shift between new bone formation and existing bone reabsorption, resulting in an important equilibrium that results in osteoporosis or other bone pathologies if disrupted.  Specifically, overstimulation of RANKL activity has been linked to osteoporosis, osteopetrosis, arthritis and additional bone malignancies. 

trance antibody

In the presence of Recombinant Mouse M-CSF (20 ng/mL, Catalog...

KLF4 as a transcription factor in stem cell differentiation

Friday, June 3, 2016 - 12:58

Krüppel-like factors (KLFs) are evolutionarily conserved zinc finger transcription factors that play a role in cell differentiation, proliferation, and pluripotency. KLF4 has specifically been tied to many diverse cellular processes, including self-renewal, apoptosis, and the correct development of the barrier function of skin.  KLF4 can act as both an activator and a repressor, with these functions often being initiated during embryonic development.  Not surprisingly, KLF4 is highly expressed in the skin and gut, and aids in kidney and skeletal development.  Mutations in KLF4 have led to metabolic disorders, cardiovascular disease and many various cancers.  In fact, KLF4 has been as shown through research to have the ability to reprogram adult fibroblasts into induced pluripotent stem cells, and the reprogramming of cancer cells with pluripotency factors has been recently proposed as a potential cancer therapy.

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How Adenovirus and Adeno-Associated Virus Work as Gene Therapy Vectors

Wednesday, June 1, 2016 - 14:38

Adenoviruses comprise a family of medium sized, non-enveloped viruses that were originally isolated from human adenoids (Rowe et al., 1953). These viruses contain a double stranded DNA genome within an icosahedral nucleocapsid capable of penetrating an endosome without the need for envelope fusion. Researchers using adenovirus antibodies have since identified more than fifty human adenovirus serotypes, which are known to cause a variety of diseases; including upper respiratory tract infections, gastroenteritis, conjunctivitis, and cystitis. Several types have even demonstrated oncogenic potential.

Recombinant adenoviruses have long been seen as useful gene therapy vectors (Heubner et al, 1964), due to their ability to encode proteins without integrating into the host cell genome (Roy-Chowdhury et al., 2002). As adenoviruses infect a host cell, their DNA is not incorporated into the cell's...

ABC Membrane transporters and the role of MRP1 in drug resistance

Thursday, May 26, 2016 - 10:39

ATP-binding cassette (ABC) transporters, alongside ion channels and aquaporins, are ubiquitous membrane-bound proteins that move substrates across extra and intra cellular membranes.  Multidrug resistance-associated protein 1 (MRP1) is a member of the superfamily of ATP-binding cassette (ABC) transporters, and in humans is encoded by the ABCC1 geneIn addition to endogenous substrate exchange, ABC transporters also participate in the movement of drugs and chemicals across cell surface and cellular organelle membranes, suggesting that defects in these genes are of great importance in cancer therapy and pharmacokinetics.  In fact, MRP1 was initially identified due to its ability to yield multidrug resistance in lung cancer cells.  MRP1 is one of many genes that may alter a tumor cell to expel cancer drugs and deem them ineffective. Specifically, MRP1 acts as a pump, disposing of cytotoxic chemicals from tumor cells. Drug resistance in chemotherapy is a constant...

Why LC3B Antibodies Make Ideal Autophagosomes Membrane Markers

Tuesday, May 24, 2016 - 15:07

The human form of microtubule-associated protein light chain 3 (LC3) is expressed as 3 splice variants LC3A, LC3B, and LC3C.1 LC3B is a subunit of the MAP1A and MAP1B microtubule-binding proteins and plays a central role in autophagosome membrane structure. This ubiquitin-like modifier is known to be involved in early stages of autophagosome formation and specifically with phagophore membrane elongation. LC3B also interacts with autophagy receptors such as p62/SQSTM1 and NBR1 during substrate selection for autophagic degradation.2

 

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Controls for HIF-1 Alpha's WB, ICC-IF, IHC, IP & FLOW Analysis

Friday, May 20, 2016 - 13:57

Tips on positive and negative controls for HIF-1 alpha antibodies is one of the most Frequently Asked Questions on Hypoxia and HIFs. Here are top 5 suggestions from Novus Biologicals:

  1. The degradation of HIF1 alpha is the most common issue which often results in either a weaker specific signal and/or the appearance of multiple degraded protein bands in Western blot (WB). Degradation may be avoided by preparing the lysates quickly (on ice/at 4˚C) after the collection of cells or tissues, preferably in a hypoxic chamber. For differentiating the target band from degradation (40-80kDa) or dimer (200+ kDa) bands, we suggest including a control based on true hypoxia or hypoxia mimetic samples (e.g. cells treated with CoCl2). Novus offers the following ready to use lysates for HIF-1 analysis.

NFkB and p62 Both Activate and Regulate Inflammation

Thursday, May 19, 2016 - 14:54

Nuclear factor kappa-light-chain-enhancer of activated B cells (NFkB) is a protein complex that regulates DNA transcription and is a critical regulator of cell survival. NFkB has long been known as a primer of inflammation, however researchers are now finding that NFkB may also regulate over-inflammation via a novel mitophagy pathway (Minton, 2016).

NFkB proteins are structurally homologous with retroviral oncoproteins originally known as v-Rel, and are now classified together as NF-κB/Rel family proteins. These include NFkB1 p50/p105, NFkB2 p52/p100, RelA/NFkB p65, RelB and c-Rel, which can function together as dimeric transcription factors to regulate gene expression via the NFkB signaling pathway (Gilmore 2008).

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The TGR5 Receptor and metabolic disease

Tuesday, May 17, 2016 - 12:43

The bile acid-responsive G-protein-coupled receptor TGR5 is widely distributed across the human body - including the endocrine glands, adipocyte cells, muscles, immune organs, spinal cord, and the enteric nervous system. G protein coupled receptors (GPCRs) are incredibly versatile signaling molecules that are activated by a number of ligands, which in turn regulate various signaling pathways. Select G proteins stimulate activity, whereas others have inhibitory effects.  The effect of TGR5 activation depends on the tissue where it is expressed and the signaling cascade that it induces.  Specifically, bile acids initiate the activation of the TGR5 receptor.  BA’s primary role are to facilitate the uptake and absorption of lipids, making their receptors important for bile acid synthesis and metabolism, as well as integration of multiple homeostatic functions in the liver and gastrointestinal tract.  Since its discovery, TGR5 has been...

Wnt-5a Antibodies Help Understand Wnt Mediated Signaling in Embryogenesis and Various Diseases

Friday, May 13, 2016 - 14:00

Wingless-Type 5A (Wnt-5a) is a member of the WNT family of secreted signaling proteins that regulate many important developmental processes including cell proliferation, migration, differentiation, fate determination and embryonic patterning. WNT signal proteins affect the cell via three known WNT signal transduction pathways. The canonical WNT signaling pathway regulates gene transcription, the non-canonical planar cell polarity pathway regulates cytoskeletal formation, and the non-canonical Wnt/calcium pathway regulates cellular calcium levels.

Wnt5a signals through both the canonical and non-canonical WNT pathways and plays an essential role in regulating developmental pathways during embryogenesis. Mutations in the Wnt5a gene are associated with Robinow syndrome (Roifman et al., 2015) and may also play a role in oncogenesis.

Recently, Wnt5a has been shown to regulate embryonic cell proliferation and differentiation in...

Understanding the relationship between HIF-1 alpha, Hypoxia and Epithelial-Mesenchymal Transition

Thursday, May 12, 2016 - 11:02

Epithelial-mesenchymal transition (EMT) is a natural process by which epithelial cells lose their polarity and intercellular adhesion, and gain the migratory invasive properties of mesenchymal stem cells that can differentiate into a variety of cell types. EMT is critical to many developmental processes including embryo development and wound healing. However, EMT is also a fundamental step in the initiation of metastasis during cancer progression.

Hypoxia is known to induce EMT via HIF-1 alpha induction. Researchers have used HIF-1 alpha antibodies (NB100-105), (NB100-449) and (NB100-479) to help identify the molecular mechanisms...

How DOPA Decarboxylase Affects Neurotransmitter Synthesis

Thursday, May 12, 2016 - 11:01

DOPA decarboxylase (DDC) is responsible for catalyzing the conversion of aromatic amino acids into their corresponding amines during the synthesis of several important neurotransmitters. Specifically, DDC catalyzes the decarboxylation of L-DOPA to dopamine, L5-HTP to serotonin, L-histidine to histamine, phenylalanine to phenethylamine, L-tyrosine to tyramine, and tryptophan to tryptamine.

A number of mutations in the DDC gene can cause aromatic L-amino-acid decarboxylase deficiency (AADCD) (Gücüyener et al., 2014). AADCD is an inborn error in neurotransmitter metabolism that leads to combined serotonin and catecholamine deficiency. DDC's critical role in neurotransmitter synthesis makes it an important target in the study of Parkinson's disease, depression and other neuroscience related diseases.

Parkinson's patients experience motor system symptoms due to reduced levels of dopamine in the substantia nigra portion of the brain. The conversion of L-DOPA...

STING in Innate Immunity and Cancer: What’s the Buzz About?

Tuesday, May 3, 2016 - 15:29
STING (STimulator of INterferon Genes protein) acts as a sensor of cytosolic DNA. Bacteria/Virus or self-derived DNA in the cytosol activates the STING pathway and promotes the production of type I interferons (IFN-alpha and IFN-beta). STING also participates in cell death signaling through its association with MHC-II and the ERK pathway. STING has been suggested to interact with DDX58/RIG-I, MAVS, SSR2, RNF5, TRIM56, TBK1, IFIT1 and IFIT2. It generally localizes to the cytoplasm and membranes of the cell, ER, and mitochondria; however, in response to DNA stimulation, it translocates to the perinuclear region and interacts with TBK1 kinase. STING’s phosphorylation by TBK1 at Ser-358 results in STING activation. STING executes its role by sensing and binding cyclic di-GMP/c-di-GMP and cyclic GMP-AMP/cGAMP. This binding results in the activation of NF-kappa B and IRF3 transcriptional...

EZH1 has more to offer than gene repression

Tuesday, May 3, 2016 - 15:28

EZH1 is part of the Polycomb-group family of proteins, which are responsible for remodeling chromatin in genes and modulating epigenetic silencing during development.  Specifically, EZHI is a component of PRC2, or polycomb repressive complex-2.  PRC2 interacts and modifies the histone “H3”, and is critical in maintaining gene repression.  EZH1 has the ability to mono-, di- and tri-methylate 'Lys-27' of histone H3 to form H3K27me1, H3K27me2 and H3K27me3, respectively.  EZH1 is also implicated in the maintenance of embryonic stem cells, including their differentiation and renewal.    

Margueron et al took a closer look at the mammalian homologs of EZH1 and EZH2 in order to learn more about their similarities and differences during development (1). They found that while both Ez proteins form PRC2 complexes, they carry out different repressive roles.  Ultimately, both protein complexes are efficient at...

Choline Acetyltransferase (ChAT) – a useful Immunohistochemical marker for morphological studies of neurons

Tuesday, April 26, 2016 - 07:45

Choline Acetyltransferase (ChAT) is the enzyme that is responsible for biosynthesis of the neurotransmitter acetylcholine. The majority of acetylcholine is synthesized locally at nerve terminals where ChAT catalyzes the transfer of an acetyl group from acetyl coenzyme A to choline, a process that takes place in a single step. ChAT is expressed by cholinergic neurons in the central nervous system (CNS) and peripheral nervous systems (PNS) (4), which are distributed in many different regions of the brain, spinal chord, and retina and participate in learning, memory, movement, and vision (2,4).


ChAT expression in rat spinal cord neurons, IHCImmunohistochemistry Free-Floating: Choline Acetyltransferase/ChAT Antibody [NB110-89724] - IHC...

The role of PARP-1 in the repair of single stranded break (SSB)

Friday, April 22, 2016 - 13:50

PARPs (poly ADP ribose polymerases) are DNA repair enzymes that promote single stranded break (SSB) repair by binding to DNA at the sites of SSBs and recruiting repair machinery. In humans, the PARP superfamily consists of 17 members, of which five play known roles in SSB repair. PARP-1, the most well-studied family member, is required for base excision repair and is thought to be responsible for 90% of PARP activity (5).

PARP inhibitors are a class of pharmacological agents that have been used to treat certain types of cancer, and are designed to induce cell death by preventing cancer cells from repairing damaged DNA. PARP inhibitors have been tested in various combination therapy contexts. For instance, one recent study compared radiation-induced cytotoxicity in cell culture and xenograft models of pancreatic carcinoma and found that PARP inhibition with radiation increased cell death in vitro and reduced tumor...

Using RPE65 as a tool to investigate ocular gene therapies

Tuesday, April 19, 2016 - 13:17

While not life threatening, blindness and retinal disease are profoundly debilitating and greatly affect quality of life.  Understandably, gene therapy has been subject to controversy given it’s potential effects on the rest of our cellular processes.  However, a genetically diseased eye being an isolated organ quickly becomes a promising prospect for such therapies.  Specifically, RPE antibodies are powerful diagnostic tools to test the viability of these clinical treatments. 

The RPE65 protein is organized into a thin layer of cells known as the retinal pigment epithelium (RPE). This RPE provides support to the retina, which sits behind the eye and has sensitivity to light. A mutation in RPE65 leads to retinal degeneration and LCA (Leber congenital amaurosis - an autosomal recessive childhood blindness), which results in a lack of 11-cis retinal productions and an inability to efficiently form the visual pigments rhodopsin and cone opsin....

HIF-2 alpha: HIF1A's Homologue with Similar and Divergent Functions

Thursday, April 14, 2016 - 13:19

HIF-2 alpha is a member of the heterodimeric hypoxia-inducible factors/HIFs family (HIF-1, HIF-2, and HIF-3) which contains a common beta subunit but differ in their alpha subunits. Also called as EPAS1 or Mop2, HIF-2 alpha regulates cellular adaptation to hypoxia which is involved in several biological processes such as angiogenesis, cellular survival/proliferation, energy metabolism, erythropoiesis, extra-cellular matrix functions, invasion/ metastasis, iron metabolism, pH regulation, multidrug resistance, stem cell properties. The expression of HIF-2 alpha is regulated through hypoxia-dependent protein stabilization with the help of proteins

IRE1 alpha dependent apoptotic-signaling pathway

Monday, April 11, 2016 - 12:47

Despite in depth characterization of the role of IRE1 alpha (inositol-requiring enzyme 1 alpha) in activating the unfolded protein response (UPR) in the ER - little is known about the molecular mechanisms by which this ER protein has shown to regulate intracellular calcium levels and subsequent apoptosis. Intracellular calcium homeostasis is fundamental to many physiological processes, and an increase in Ca2+ is associated with both the early and late stages of apoptosis. A Nature article fleshed out a pro-apoptotic IRE1alphaTRAF2JNK pathway that has potential to be activated by prolonged ER stress. Specifically, prolonged IRE1-mediated activation may promote apoptosis by degrading the mRNAs that encode essential cell-survival proteins. Additional research studies have proposed similar pathways that bring in other pro apoptotic...

Cleaved Caspase-3: A Marker of Programmed Cell Death

Thursday, April 7, 2016 - 13:44

What are Caspases?

Caspases, or cysteine-dependent aspartate specific proteases, are a family of enzymes crucial for initiating and executing apoptosis within a cell, an important biological event especially during organ development (1). Environmental cues and cellular signals trigger the initiation of the programmed cell death cascade primarily through proteolytic activation of the caspases (1). One specific effector caspase is caspase-3, a protein that is cleaved and thus activated upon the initiation of apoptosis. Cleaved caspase-3 propagates an apoptotic signal through enzymatic activity on downstream targets, including poly ADP ribose polymerase (PARP) and other substrates (2). In cell biology, caspase-3 antibodies that detect both uncleaved and cleaved versions of the enzyme are strong indicators...

The subunit RelA(p65) mediates NF-kB signal transduction in multiple ways

Thursday, March 31, 2016 - 11:00

RelA (also known as p65) is an NF-kB family member and a subunit of the NF-kB transcription factor complex.  The mammalian NF-kB family has five members (NF-kB1, NF-kB2, RelA (p65), RelB, and c-Rel), each of which contains an N-terminal Rel homology domain. Active NF-kB protein complexes are dimeric (hetero- or homo-), and are made up of two family members. NF-kB signaling is activated in response to many different types of stimuli and modulates transcription of numerous downstream targets. NF-kB-mediated signaling plays known roles in inflammatory and immune responses (Hayden and Ghosh, 2008), as well as neuronal development and synaptogenesis (Boersma et al., 2011; Gutierrez et al., 2005).  Aberrant NF-kB activity has also been linked to various human diseases including a number of cancers (Perkins, 2012).

In the central nervous system, NF-kB activity is dependent on translocation to the nucleus, where the complex binds to DNA...

Three things everyone studying autophagy should know

Friday, March 25, 2016 - 09:36

Novus Biologicals' antibodies are the gold standard to monitor autophagy and detect LC3 expression. The recently published Guidelines for the Use and Interpretation of Assays for Monitoring Autophagy (3rd Edition) comprehensively details methods to monitor autophagy in cell or tissue samples. Importantly, these guidelines also provide key considerations for data interpretation and tips to creating better western blot data.  

Use fresh samples and avoid multiple freeze thaws to improve detection of LC3-I when possible.

Why? LC3-I is less stable and more susceptible to freeze thaws and degradation in SDS compared to LC3-II. Moreover, most LC3 antibodies are less sensitive to LC3-I...

Multifaceted Roles of Matrix Metalloproteinase-2 (MMP2) in Normal and Disease State

Monday, March 21, 2016 - 13:25

MMP2 is a 72 kDa enzymatic protein and it belongs to matrix metalloproteinases (MMPs), a heterogenous family of zinc/calcium-dependent TIMPs (tissue inhibitors of matrix metalloproteinases) regulated matrix-degrading endopeptidases which are classified into collagenases (MMP-1, -8, -13, -18), gelatinases (MMP-2, -9), stromelysins (MMP-3, -7, -10, -11), elastase (MMP-12), and membrane-type matrix metalloproteinases (MT-MMP-1 through -5) (1). MMP2 involves in extracellular matrix metabolism and cleaves type IV collagen along with degrading the already denatured collagens. TIMP2 and MT-MMP1 (membrane type MMP, MMP14) regulate the activity of MMP2, and the cleavage of pro-MMP2 to active-MMP2 is dependent upon MMP14. MMP2 is expressed ubiquitously and it implicates in a diverse array of functions such as vasculature remodeling, angiogenesis, tissue repair, tumor invasion, inflammation, and atherosclerotic plaque rupture. Mutations in MMP2 gene has been linked to...

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