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In This Issue
|Get More Physiologically Relevant Results — Gibco® Primary Human Corneal Epithelial Cells (HCECs)|
|Study c-Met Activation With New Recombinant Antibodies — ABfinity™ Rabbit Monoclonal Antibodies|
|Measure Phosphorylation of Tau Proteins — Tau [pT231] Human ELISA Kit|
|Discovering O-GlcNAc Sites on Proteins — Click-iT® Glycoprotein Profiling Reagents|
|Molecular Probes® Photostream!
Easily browse and share amazing cell images on our Flickr® site!
|BioProbes 64 — Now Available Online
FEATURED NEW PRODUCTS
what they are
Human Corneal Epithelial Cells (HCECs) from Gibco® are normal human cells isolated from the progenitor-rich limbal region of the eye, and are cryopreserved at the end of the secondary culture. HCECs are ideal for research on corneal biology, including inflammation and wound healing, investigating the effects of chemicals and components in consumer products, and other studies of ocular function.
what they offer
- Guaranteed to be ≥70% viable upon thawing and to contain ≥500,000 viable cells/vial
- Guaranteed to reach at least 12 population doublings after thawing when using Keratinoctye-SFM
- Stain positive for corneal epithelial markers cytokeratin 15 and p63 alpha
how they work
Cryopreserved HCECs are optimal for investigating the cellular, molecular, and biochemical processes that occur in the cornea and have been optimized for use with Gibco® Keratinocyte Serum-Free Medium. HCECs closely mimic the in vivo state and enable generation of physiologically relevant data. Limbal tissue is known to be enriched for corneal epithelial progenitor cells. Our robust isolation and expansion process yields large single-donor lots, to help ensure availability of consistent product.
- Learn More About Human Corneal Epithelial Cells
- Learn More About Gibco® Cell Culture
Gibco® Primary Human Corneal Epithelial Cells (HCECs).
Left: HCECs imaged using Hoechst 33342, Alexa Fluor® 488 phalloidin, and anti-PMP70 antibody (a component of the SelectFX® Peroxisomal Labeling Kit) labeled with a goat anti-rabbit Alexa Fluor® 647 secondary antibody. Right: HCECs imaged using the Click-iT® EdU Alexa Fluor® 488 Imaging Kit, an anti–α-tubulin antibody labeled with a goat anti-mouse Alexa Fluor® 555 secondary antibody, and Hoechst 33342.
|Human Corneal Epithelial Cells (HCEC)||1 vial||C0185C|
|Keratinocyte-SFM (1X), liquid||500 mL kit||17005042|
what it is
The c-Met receptor is a potential therapeutic target in some cancer models. c-Met is activated by phosphorylation at tyrosine residues, and can be activated by epidermal growth factor receptor (EGFR) without production of hepatocyte growth factor (HGF), inducing signaling cascades through a ligand-independent event.
what it offers
- ABfinity™ antibodies—recombinant antibodies enable consistent results, time after time
- New antibodies released every month
how it works
ABfinity™ recombinant rabbit monoclonal antibodies help ensure consistent antibody performance lot after lot, so you don’t have to revalidate dilutions for your experiments when you order more. c-Met ABfinity™ Recombinant Rabbit Monoclonal Antibodies are available for total c-Met and c-Met phosphorylated at tyrosine 1230, and are validated in applications ranging from western blotting to immunofluorescence. ABfinity™ Recombinant Rabbit Monoclonal Antibodies are also available for EGFR.
- Learn More About ABfinity™ Recombinant Rabbit Monoclonal Antibodies
- Search for Primary and Secondary Antibodies
Immunocytochemistry of A549 cells labeled with rabbit anti–c-Met antibody.
what it is
The Invitrogen™ Tau [pT231] Human ELISA Kit is designed to detect and quantify the level of threonine-231 phosphorylation in tau proteins from human cell lysates and cerebrospinal fluid (CSF). This validated and complete phosphoELISA™ kit contains all the buffers and reagents you need to quickly and easily perform the assay and obtain reliable results.
what it offers
- Validated on SH-SY5Y cell lysates and CSF
- Rapid 4-hour protocol
- Precoated removable 8-well strips
how it works
The Invitrogen™ Tau [pT231] Human ELISA Kit is a solid-phase sandwich enzyme-linked immunosorbent assay (ELISA).
A monoclonal antibody specific for tau (regardless of phosphorylation state) has been coated onto the wells of the microtiter strips provided. Samples are pipetted into these wells. During the first incubation, the tau antigen binds to the immobilized (capture) antibody. After washing, a rabbit antibody specific for tau [pT231] phosphorylation is added to the wells. During the second incubation, this antibody serves as a detection antibody by binding to the immobilized tau protein captured during the first incubation. After removal of excess detection antibody, a horseradish peroxidase–labeled anti-rabbit IgG (anti-rabbit IgG HRP) is added. This binds to the detection antibody to complete the four-member sandwich. After washing, a substrate solution is added, which is acted upon by the bound enzyme to produce color. The intensity of this colored product is directly proportional to the concentration of tau [pT231] present.
- Learn More About the Invitrogen™ ELISA Kits
In this study, the researchers isolated and digested the histones, yielding peptides. These peptides were then treated with phosphatase, leaving O-GlcNAc modifications intact. Then they used a product similar to the Click-iT® O-GlcNAc Enzymatic Labeling System, wherein β-1,4-galactosyltransferase (Gal-T1) transfers azido-modified galactose (GalNAz) from UDP-GalNAz to O-GlcNAc residues on target proteins in a highly specific reaction. For detection, the researchers used a product similar to the Click-iT® Biotin Protein Analysis Detection Kit followed by mass spectrometry to detect the peptides and thus the exact O-GlcNAc modification sites.
This study illustrates the specificity and precision of click chemistry used to study the elusive sites of O-GlcNAc modifications. The click reaction is highly specific and the reaction product contains an irreversible covalent bond, making the technique ideal for accurate downstream identification with mass spectrometry.
Click-iT® Glycoprotein Detection. (A) Enzymatic labeling of an O-GlcNAc–modified protein with UDP-GalNAz and Gal-T1. (B) Click-iT® azide/alkyne reaction.
- Learn More About Click-iT® Tools for Posttranslational Modification Analysis
|Click-iT® O-GlcNAc Enzymatic Labeling System, for N- or O-linked GlcNAc glycoproteins||10 labelings||C33368|
|Click-iT® Biotin Protein Analysis Detection Kit||10 reactions||C33372|
|Click-iT® Tetramethylrhodamine (TAMRA) Protein Analysis Detection Kit, UV/532 nm excitation||10 reactions||C33370|
|Click-iT® Dapoxyl® Protein Analysis Detection Kit, for UV excitation||10 reactions||C33371|
|Click-iT® O-GlcNAc peptide and phosphopeptide LC/MS standards||1 set (5 nmol each)||C33373|
|Click-iT® O-GlcNAc peptide LC/MS standard||5 nmol||C33374|
All six of our anti-GFP antibodies are suited for detection of native GFP, GFP variants, and most GFP fusion proteins. The affinity-purified anti-RFP antibody is used to detect native TagRFP and most fusion proteins derived from Entacmaea quadricolor. The RFP proteins derived from E. quadricolor have 2.8 times the quantum yield of mCherry, and more importantly, they remain as monomers, making it more likely that the fusion protein will function properly in the cell .
- Learn more about GFP Antibodies and Antibody Conjugates
- Read the BioProbes Article on GFP and RFP Antibodies
|Anti-GFP ABfinity™ Recombinant Rabbit Monoclonal Antibody used for immunocytochemistry. Left: U2OS cells expressing CellLight® ER-GFP were incubated with the anti-GFP ABfinity™ Recombinant Rabbit Monoclonal Antibody. Center: Cells were formaldehyde-fixed, permeabilized, and blocked in 1% BSA, then incubated with primary antibody at 1 μg/mL, followed by Alexa Fluor® 647 goat anti–rabbit IgG conjugate. Right: The merged yellow signal indicates colocalization of GFP fluorescence and the detection antibody. Nuclei were stained with Hoechst 33342.|
|Anti-GFP, rabbit serum (polyclonal)||ICC, IHC, IP, WB||A6455|
|Anti-GFP, chicken IgY fraction||ICC, WB||A10262|
|Anti-GFP, rabbit IgG fraction||ICC, IHC, IP, WB||A11122|
|Anti-GFP, mouse IgG2a||ICC, IHC, IP||A11120|
|Anti-GFP, mouse IgG1||ICC||A11121|
|Anti-GFP, rabbit monoclonal||ICC, IHC, IP||G10362|
|Anti-RFP, rabbit IgG polyclonal||ICC, IHC, IP, WB||R10367|
|Anti-GFP, rabbit IgG fraction, Alexa Fluor® 488 conjugate||ICC, IHC||A21311|
|Anti-GFP, rabbit IgG fraction, Alexa Fluor® 555 conjugate||ICC, IHC||A31851|
|Anti-GFP, rabbit IgG fraction, Alexa Fluor® 594 conjugate||ICC, IHC||A21312|
|Anti-GFP, rabbit IgG fraction, Alexa Fluor® 647 conjugate||ICC, IHC||A31852|
|*ICC = immunocytochemistry; IHC = cryosection immunohistochemistry; IP = immunoprecipitation; WB = western blot.
Imaging the Golgi Complex and Tubulin in a Rat Kidney Epithelial Cell.
|Alexa Fluor® 488 donkey anti–rabbit IgG (H+L), 2 mg/mL||0.5 mL||A21206|
|Texas Red® goat anti–mouse IgG (H+L), 2 mg/mL||0.5 mL||T862|
|Hoechst 33342, trihydrochloride, trihydrate, 10 mg/mL solution in water||10 mL||H3570|
Hemsley AL, Hernandez D, Mason C et al. (2011) Cell Health and Cytoskeleton 3:23–34.
Recent studies have revealed that embryonic stem cell (ESC) proliferation and differentiation can be influenced by exogenous mechanical forces. To further investigate the effect of these forces on mouse ESCs (mESCs), Hemsley et al. combined atomic force microscopy with laser scanning confocal microscopy to characterize morphological and biochemical responses of mESCs to precisely delivered nanomechanical forces. The researchers identified two morphologically distinct subpopulations of mESCs: round and flattened. Using phalloidin conjugated to Alexa Fluor® 546 or Alexa Fluor® 488, immunofluorescence imaging of the cytoskeleton revealed that round cells, but not flattened cells, exhibited blebbing in response to mechanically induced forces. Flattened cells were characterized by a more highly developed cytoskeleton and a stronger mechanical link between the plasma membrane and cytoskeleton. These results suggest that mechanosensitivity of ESCs at the earliest stages of differentiation may play an important role in ESC biology.
- View the Bibliography Reference
- Learn more about Phalloidin and Phalloidin Conjugates for Staining Actin
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