antibodies-online.com | News | Research Areas

JNK pathway

news@antikoerper-online.de (David Kitz Krämer) — Fri, 15 Jul 2011 15:27:00 +0200

Receive a 10% discount for recommending us!

news@antikoerper-online.de (David Kitz Kramer) — Wed, 20 Oct 2010 13:30:00 +0200

As a content customer of antibodies-online.com you would like to recommend us?
A great way of recommending us is by linking to us on your company's or institute's website. We reward you sharing our link with a 10% discount on your next order!

You are impressed with the breadth of products we offer and would like to order?
Help us spread the word that antibodies-online.com is a great resource for research reagents, with more than 270.000 antibodies, 31.000 ELISA kits, and many more complementary research products and save 10% on your initial order with us!

All you need to do is to link to us and provide us with the location of the website where you put the link when ordering the next time! Our ordering department will deduce the rebate after checking your information.

Want more info? Please contact us via our »contact page or mail us to info@antibodies-online.com.

Metabolism

news@antikoerper-online.de (David Kitz Kramer) — Tue, 15 Jun 2010 16:21:00 +0200

Metabolism deals with the construction (anabolism) and destruction (catabolism) of organic macromolecules in living organisms
Metabolism is tightly controlled and facilitated by enzymes and signaling-molecules
antibodies-online has a range of tools designed to support your research on metabolism

Type 2 Diabetes mellitus (T2D)

news@antikoerper-online.de (David Kitz Kramer) — Wed, 17 Mar 2010 11:00:00 +0100

Diabetes Type II is caused by a reduction of insulin sensitivity.
Diabetes ranks in the top 5 for mortality in developed countries.
Obesity and sedentary life-style are largely to blame for the diabetes epidemic.
Adipocyte-secreted factors can induce insulin resistance in skeletal muscle.
antibodies-online offers a large number of well established antibodies for research on Type 2 Diabetes Mellitus.

Autophagy

news@antikoerper-online.de (David Kitz Kramer) — Mon, 08 Mar 2010 17:04:00 +0100

Autophagy acts as a maintenance apparatus which keeps the cell functioning properly by recycling "waste"
In principle autophagy assists in protecting the organism against pathologies. Malfunctions of autophagy may on the other hand promote disease progression
For further studying autophagy and related processes antibodies-online offers a number of well established antibodies

Proteases

news@antikoerper-online.de (David Kitz Kramer) — Fri, 19 Feb 2010 09:38:00 +0100

Proteases (peptidases) are enzymes with the ability to break hydrolytic peptide bonds in a protein- or polypeptide molecule. They exist in almost all tissues and cells of any organism. Generally, two types of proteases are distinguished, i.e. intracellular proteases which carry out regulatory tasks in cell compartments, thereby regulating the protein content of the cell. Newly synthesized protein functionality can be activated by cleaving off peptide fragments, for example. Signal proteases on the other hand cleave off peptides that act as signaling component, which leads to their transport to their designated place of action. Additionally, intracellular peptidases are involved in the processing of antigens.

In this context the cytoplasm and the proteasome in the nucleus are of crucial importance. The large peptidase-complex (of approximately 11 by 17 nanometers) recognizes proteins that have been labeled with a ubiquitin chain, which designates them for disassembly into peptides. This process assures destruction of faulty, damaged or simply superfluous proteins. The extracellular peptidase are found mainly in the intestines of higher organisms. They catalyse the hydrolytic cleavage of foods. They may possess highly specific functions in other extracellular fluids, for example in the clotting system of the blood, the complement system (involved in immune function) and the fibrinolytic system. Inhibitors of protease function are for example alpha1-antitrypsin, iodacetate and aprotinin.

Cytoskeleton

news@antikoerper-online.de (David Kitz Kramer) — Thu, 18 Feb 2010 17:24:00 +0100

The cytoskeleton is a system of fibers- and filaments located in the cytoplasm. Its functions are the transport of cellular structures, like for example mitochondria and vesicles, the anchoring of cell-organelles, and the maintenance of the cell shape and structure. The eukaryotic cytoskeleton consists of three main components, namely actin filaments, microtubules, and the intermediary filaments. Furthermore, there are a large number of proteins bound to these main components that fulfill various and diverse functions.

Actin filaments consist of the polymerized protein actin and are organized in a fibre-like double-helix structure with a diameter of approximately seven nanometers. They play an important role in stabilizing and altering the cell geometry and in the transport of vesicles. By binding to phalloidin, a substance from the group of pallotoxins, they can be labeled and detected by fluorescence microscopy. Microtubuli are dynamic and hollow cylinders of 25 nanometers diameter, which consist of polymers made up by tubulin subunits.

With their motorproteins dynesin and kinesin they allow intracellular transport over long distances and support the fixation of cell organelles. The intermediary filaments have structuring functions for the plasma membrane and the nucleus. There are six subtypes of the main components, namely sour and basic ceratin, desmins (GFAB, desmin, vimentin, peripherin), lamin (lamin A, lamin B and lamin C), and the neurofilaments (NF-L, internexin, NF-M, NF-A, nestin). Their diameter is intermediate between that of actin filamens and microtubli.

Hint: on antibodies-online.com you will find more than 1.100 antibodies specific for proteins of the cytoskeleton.

Heat-Shock Proteins

news@antikoerper-online.de (David Kitz Kramer) — Thu, 18 Feb 2010 15:47:00 +0100

Heat shock proteins (HSP) support the maintenance of three dimensional structures of proteins for instance by protecting them from denaturation due to heat. They can be found everywhere in the organism and are expressed extensively, for example, under stress condition caused by exposure to high heat, UV-rays or ethanol.

Many Heat shock proteins belong to the family of chaperons which play a role in protein translocation, and folding and assembly, also under standard conditions. Chaperons do not contain information about the protein specific three dimensional folding but generally accelerate and facilitate folding by inhibiting aggregation and defective bindings. HSPs are distinguished in categories according to their molecular weight.

The most researched heat-shock proteins are hsp60, hsp70 and hsp90. The numerical value is the molecular weight in kilo Daltons. Hsp60 is an important component of the chaperon system in animal organisms. Hsp60 recognizes collapsed substrate proteins, which would aggregate otherwise, and folds them actively under consumption of ATP. Hsp70 on the other hand helps to maintain the unfolded condition of target proteins.

The chaperone hsp90 family proteins are ubiquitous in prokaryotes and eukaryotes and apparently prevent the final steps of the protein folding process. Hsp90 interact with actin and tubulin and in concert with hsp70, as well as others, function as a supramolekular complex.

Leukemia

news@antikoerper-online.de (David Kitz Kramer) — Wed, 17 Feb 2010 14:49:00 +0100

Leukemia is a cancer of blood cells and the bone marrow. The name "Leukemia" derives from the greek terms for white (leukos) and blood (aima) indicating, that it is a disorder affecting the white blood cells, the leukocytes. When affected by Leukemia the leukocytes proliferate abnormally. Other cells of the plasma, such as erythrocytes (red blood cells) and thrombocytes (platelet cells) for instance are not affected. In 2000, approximately 256,000 children and adults around the world developed a form of Leukemia, and 209,000 died from it [1] .

Major Histocompatability Complex (MHC)

news@antikoerper-online.de (David Kitz Kramer) — Thu, 11 Feb 2010 14:39:00 +0100

The major histocompatability complex (MHC) includes a variety of genes in vertebrates, which are responsible for the histocompatibility of tissues in transplantations, due to their function in immune recognition, amongst others. MHC-protein complexes are expressed, and act as antigens, on the surface of every cell that is involved in immunological functions. There are two major classes of MHC with distinct pathways and functions.

The MHC-Klasse I pathway allows recognition and elimination of dysfunctional cells by T-cells (killer cells). The MHC-Klasse I can be found on almost all nuclei surfaces of the organism and serve as presenters of antigens in order for T-cells to recognize them for termination.

MHC-Klasse II are presented by antigen presenting cells (APC) and allow T-cells to recognize them. Monocytes and macrophages, amongst others, belong to the APC. They move to the endoplasmatic reticulum (ER) and are associated with the invariant chain. The latter associates with another invariant chain constituting a homotrimer. This complex is bound to calnexin and leaves the ER.

Proteases cleave the invariant chains in multiple locations, leaving behind the class-II-associated invariant chain peptide (CLIP) in the binding pocket. If dissociated the MHC-Klasse II becomes active.

Extracellular matrix

news@antikoerper-online.de (David Kitz Kramer) — Thu, 11 Feb 2010 12:13:00 +0100

The extracellular matrix (ECM) is the part of the tissue that is situated outside of animal cells within the intercellular space. Fibroblasts that are situated in connective tissue express collagen, which, in combination with proteoglycans, is crucial for the stability of the ECM.

The biological functions of the ECM are multifaceted and include the shaping of tissues and organs, stabilization of bones, elasticity and tensile strength of tissues, support of signal transduction, and the storage and supply of water, nutrition and hormones.

The extracellular matrix consists of fibers and a basic compound. The basic compound is heterogenic and is composed of glycosaminoglycanes (GAG),proteoglycans and different adhesion proteins, as for example laminin, vitronectin or fibronectin. In histological sections, the space these substances occupy between fibers appears empty.

The fibrous component is dominated by the collagen family of proteins, which form various types of fibers and are part of almost every tissue. The GAGs, which are carbohydrates, associate with proteins and form large complexes of macromolecules that belong to the proteoglycan family. The multitude of possible interactions of these proteins and molecules is the basis for the large spectrum of functions the extracellular matrix exhibits.

Cytokeratins in the detection of tumors

news@antikoerper-online.de (David Kitz Kramer) — Fri, 01 Jan 2010 16:03:00 +0100

Cytokeratins (CKs, or following more recent nomenclature also simply called keratins) are intermediate filament–forming proteins that provide mechanical support and fulfill a variety of additional functions in epithelial cells. They are part of the cytoskeleton and the largest family of intermediate filament proteins. Two types of Cytokeratins are distinguished that form heterodimers, namely acidic type I (Cytokeratins 9-23) and basic type II (Cytokeratins 1-8).

Apoptosis

news@antikoerper-online.de (David Kitz Kramer) — Fri, 01 Jan 2010 13:09:00 +0100

Apoptosis is a type of cell-death. In contrast to necrosis, apoptosis is a process initiated by the cell itself. Apoptosis takes place as part of cell-internal processes and hence does not harm surrounding cells. It is a two-phase process, divided into the initiation- and the effector phase. The initiation phase can further be divided into the extrinsic pathway (type 1 apoptosis) and the intrinsic pathway (type 2 apoptosis). The extrinsic pathway takes place via the trimerisation of a receptor of the TNF-alpha family (TNF-alpha), denominated the death receptor. Subsequently, the trimers bind adaptor-molecules that are bound via a domain that is called the death-domain. By recruitment of the proteins TRADD and FADD the caspase cascade is triggered via caspase 8, ultimately leading to a feedback that causes activation of further caspase 8 molecules.

The intrinsic pathway apparently occurs due to release of cytochrome C from the mitochondria into the cytoplasm. Severe DNA damage, for instance, can trigger this pathway via the tumor suppressor p53. The protein p53 stimulates expression of pro-apoptotic factors like the Bcl-2 protein family.

The effector phase eventually leads to cell death. One of the molecular effects leading to cell death is that lamin and actin are degraded.