1510 Results for: "assay 6-50"

Supplier: VWR

VWR® Phenol-FreeTotal RNA Purification Kit provides a rapid method for the isolation and purification of total RNA from cultured animal cells, tissue samples, blood, bacteria, yeast, fungi, plants and viruses.

Supplier: Genetex

The RNAs that direct protein synthesis in animals and plant cells are synthesized in the nucleus as large precursors (pre-mRNAs). The protein coding sequences in pre-mRNA molecules are arranged in discontinuous segments - exons interspersed with noncoding sequences - introns. In a process termed splicing, these introns are efficiently removed before the pre-mRNA is transported from the nucleus to the cytoplasm, where it is translated into protein. Studies have shown that nuclear pre-mRNA splicing takes place in a multi-component structure termed a spliceosome. The polypyrimidine tract-binding (PTB) protein-associated splicing factor (PSF), which plays an essential role in mammalian spliceosomes, is a ubiquitous nuclear matrix protein. A complex between PTB and PSF is necessary for pre-mRNA splicing. PSF contains two consensus RNA-binding domains and an unusual amino terminus rich in proline and glutamine residues. The RNA-binding properties of PSF are apparently identical to those of PTB. Both proteins, together and independently, bind the polypyrimidine tract of mammalian introns. However, the nuclear localization of PSF and PTB and their distribution in subnuclear fractions differ markedly: isolated nuclear matrices contain a bulk of PSF, but only minor amounts of PTB. In confocal microscopy both proteins appear in speckles, the majority of which do not co-localize. These PTB/PSF complexes, as well as the observed PSF-PTB interaction, may reflect the presence of PTB and PSF in spliceosomal complexes during RNA processing, although other data point to different cellular distribution and nuclear matrix association of the majority of PSF and PTB. The cleavage of PSF during lysis of immature myeloid cells is accompanied by digestion of the PTB splicing regulator but not other proteins tested. In contrast, during apoptosis PTB is degraded while PSF remains intact. Proteolytic degradation of PSF specifically occurs in intact myeloid cells and this process is enhanced upon immature myeloid cell lysis; PSF is completely cleaved to a 47 kDa proteolytic cleavage product (p47), due to potent proteolytic activity found in these cells but rare in other cells and tissues. Furthermore, p47 is abundant in intact normal and tumor myeloid cells while in other cell types it is undetectable. The bone marrow 47 kDa protein is a fragment constituting the N-terminal, protease-resistant half of the splicing factor PSF. PSF is highly basic and migrates anomalously on SDS gels. The 47 kDa protein of mouse cells of immature myeloid origin (bone marrow and acute myeloid leukemia) exhibits a gel migration pattern corresponding to a 49 kDa molecule. In other cell types such as lymphoid cells and in peripheral blood cells, PSF appears as approx. 100 kDa or 75 kDa molecules. The sequence of a fragment of mouse PSF was found to be remarkably similar to that of human PSF ( > 98% homology). Also, the sequences of PSF and the human (h) 100 kDa DNA-pairing protein (hPOMp100) reveals identity. Homologous pairing is a fundamental biological reaction implicated in various cellular processes such as DNA recombination and repair, chromosome pairing, sister chromatid cohesion and chromosome condensation, gene inactivation and initiation of replication. The base pairing is also involved in spliceosome assembly resulting in formation of a dynamic Holliday-like structure within which splicing occurs. Indeed, PSF/hPOMp100 bind both singlestranded (ss) and double-stranded (ds) DNA and facilitates the renaturation of complementary ssDNA molecules. Importantly, PSF/hPOMp100 promotes the formation of D-loops in superhelical duplex DNA. PSF/hPOMp100 also serves as an efficient substrate for protein kinase C (PKC) in vitro. PKC phosphorylation of PSF/hPOMp100 stimulates its DNA binding and D-loop formation activity suggesting a possible regulatory mechanism. PSF has been demonstrated to interact with a variety of cellular targets including the human pro-oncoproteins EWS, hPOMp75/TLS and calmodulin, the RNA/DNAbinding nuclear protein p54nrb/NonO (the homolog of PSF) and DNA topoisomerase. A direct interaction has been observed, between PSF and topoisomerase I which has been implied in DNA recombination, DNA repair, and chromosome formation and may act as a transcription factor and a protein kinase. PSF is also expressed by differentiating neurons in developing mouse brain. Both the expression of PSF mRNA in cortex and cerebellum and PSF immunoreactivity in all brain areas has been found to be high during embryonic and early postnatal life. In adult tissue, only various neuronal populations in the hippocampus and olfactory bulb express PSF. PSF is expressed by differentiating neurons but not by astrocytic cells including radial glia; however oligodendrocytes differentiating in vitro were found to express it. The restricted expression of PSF suggests that it is involved in the control of neuronal-specific splicing events occurring at particular stages of neuronal differentiation and maturation. Monoclonal antibodies reacting specifically with PSF are useful tools for the molecular identification and characterization of the functional activity of PSF.

Supplier: Genetex

The nuclear factor of activated T-cells (NFAT) transcription complex is required for the expression of a group of proteins that collectively regulate the immune response. Four NFAT proteins, encoded on separate genes and expressed as several splice variants, have been described: NFAT1 (also known as NFATp or NFATc2), NFAT2 (NFATc or NFATc1), NFAT3, and NFAT4 (NFATx or NFATc3). These proteins show a low level of sequence similarity with the Dorsal/Rel/NFkB family of transcription factors. Another NFAT-related protein termed NFAT5 differs from isoforms 1-4 in that it lacks many of the Fos/Jun contact sites observed in its predecessors and its subcellular localization is not calcineurin-dependent.

Supplier: IBI Scientific

The DNA/RNA/Protein Extraction Kit provides an efficient method for purifying genomic DNA, total RNA, and total protein simultaneously from cultured cells, animal tissues, whole blood, and biological fluids

Supplier: Genetex

CD95, also known as FAS or APO-1, is a 36 kDa cell surface type I- membrane glycoprotein with an apparent molecular weight of 44 kDa on SDS-PAGE. CD95 is a member of the TNF receptor family, which includes TNFR-1, TNFR-2, CD27, CD30 and CD40. Binding of CD95 Ligand to CD95 or crosslinking of CD95 by anti-CD95 monoclonal antibodies leads to apoptosis of CD95 expressing cells. CD95 belongs to a subgroup of family members that have a death domain (DD) which contains 70 amino acids near the carboxyl-terminal region of the molecule. The binding of adaptor molecules to this DD is responsible for transmitting the death signal for apoptosis. Stimulation of CD95 results in aggregation of its DD, leading to the recruitment of FADD and caspase-8 that together with the receptor form the death-inducing signaling complex (DISC).

Supplier: Molecular Devices

The GenePix® 4300A and GenePix® 4400A Scanners from Molecular Devices offer maximum imaging quality with optimal resolution in highly configurable platforms.

Supplier: Genetex

Lamins are type V intermediate filament proteins and are grouped into constitutively expressed B-type lamins and developmentally regulated A-type lamins. Lamin-binding proteins in the nuclear lamina and the nuclear interior include several protein families and/or types of proteins in higher eukaryotes such as the inner nuclear membrane proteins, lamin B receptor, emerin, and MANI, three isoforms of lamina-associated polypeptide 1 (LAP1), and several isoforms of LAP2. Up to six LAP 2 isoforms derive from a single gene by alternative splicing in mammals and various isoforms have been described in Xenopus. The best characterized LAP2 isoforms are the inner nuclear membrane protein LAP2 beta and the nucleoplasmic protein LAP2 alpha, which are identical in their N-terminal 187-amino acid constant region but differ in their C termini. While LAP2 beta binds to B-type lamins at the nuclear periphery and was suggested to regulate nuclear lamina growth , LAP2 alpha specifically interacts with A-type lamins within the nuclear interior as part of a detergent/salt-resistant nucleoskeletal structure.

Supplier: Eppendorf

Eppendorf® conical tubes with screw caps offer reliable sample containment and leak-free storage. SafeCode variants enhance sample identification, while the BioBased options, manufactured using renewable resources, provide an eco-friendly alternative without compromising performance.

Supplier: IBI Scientific

Cost-effective and non-invasive method to capture saliva samples for DNA extraction.

Supplier: Rockland Immunochemical

HER2 (human epidermal growth factor receptor 2) is a member of the epidermal growth factor receptor (HER/EGFR/ERBB) family. It is also called ERBB2, CD340 or proto-oncogene Neu. The protein is a receptor tyrosine kinase located on the plasma membrane of cells. Activation of the tyrosine kinase promotes cell proliferation and suppresses apoptosis. HER2 can dimerize with any other member of the ErbB family, which results in auto phosphorylation of tyrosine residues and activation of signal pathways. HER2 is over expressed in a significant proportion of cancer patients, resulting in an increased disease recurrence and poor prognosis. Therefore an early diagnosis of the HER2 status of the tumors is necessary to decide the appropriate treatment. Besides in breast cancer HER2 is over expressed in variety of different tumors. The over expression of HER2 makes it a target for immunotherapy of certain tumor patients. The antibody Trastuzumab (Herceptin) which recognizes HER2 was approved for the treatment of HER2 positive breast cancer patients in 1998. The original approval was for treatment of HER2 positive metastatic breast tumors. Later studies have shown that Herceptin is also beneficial for early stage HER2 positive tumor patients and it is approved as an adjuvant treatment. Additionally the antibody is now approved also for other HER2 positive tumors (metastatic gastric adenocarcinoma). This antibody is made from a humanized Fab fragment making it specific, efficient, and effective. Humanized Recombinant Anti-HER2 Fab fragment Antibody is useful for researchers interested in Cancer research.