Microsize antibodies for $99 | Learn More >>

Monoclonal Antibody Immunoprecipitation Cell Morphogenesis

$260
100 µl
APPLICATIONS
REACTIVITY
Human, Monkey, Mouse, Rat

Application Methods: Chromatin IP, Chromatin IP-seq, Immunohistochemistry (Paraffin), Immunoprecipitation, Western Blotting

Background: ATP-dependent chromatin remodeling complexes play an essential role in the regulation of nuclear processes such as transcription and DNA replication and repair (1,2). The SWI/SNF chromatin remodeling complex consists of more than 10 subunits and contains a single molecule of either BRM or BRG1 as the ATPase catalytic subunit. The activity of the ATPase subunit disrupts histone-DNA contacts and changes the accessibility of crucial regulatory elements to the chromatin. The additional core and accessory subunits play a scaffolding role to maintain stability and provide surfaces for interaction with various transcription factors and chromatin (2-5). The interactions between SWI/SNF subunits and transcription factors, such as nuclear receptors, p53, Rb, BRCA1, and MyoD, facilitate recruitment of the complex to target genes for regulation of gene activation, cell growth, cell cycle, and differentiation processes (1,6-9).

$269
100 µl
APPLICATIONS
REACTIVITY
Mouse

Application Methods: Flow Cytometry, Immunofluorescence (Frozen), Immunofluorescence (Immunocytochemistry), Immunohistochemistry (Paraffin), Immunoprecipitation, Western Blotting

Background: The epidermal growth factor (EGF) receptor is a transmembrane tyrosine kinase that belongs to the HER/ErbB protein family. Ligand binding results in receptor dimerization, autophosphorylation, activation of downstream signaling, internalization, and lysosomal degradation (1,2). Phosphorylation of EGF receptor (EGFR) at Tyr845 in the kinase domain is implicated in stabilizing the activation loop, maintaining the active state enzyme, and providing a binding surface for substrate proteins (3,4). c-Src is involved in phosphorylation of EGFR at Tyr845 (5). The SH2 domain of PLCγ binds at phospho-Tyr992, resulting in activation of PLCγ-mediated downstream signaling (6). Phosphorylation of EGFR at Tyr1045 creates a major docking site for the adaptor protein c-Cbl, leading to receptor ubiquitination and degradation following EGFR activation (7,8). The GRB2 adaptor protein binds activated EGFR at phospho-Tyr1068 (9). A pair of phosphorylated EGFR residues (Tyr1148 and Tyr1173) provide a docking site for the Shc scaffold protein, with both sites involved in MAP kinase signaling activation (2). Phosphorylation of EGFR at specific serine and threonine residues attenuates EGFR kinase activity. EGFR carboxy-terminal residues Ser1046 and Ser1047 are phosphorylated by CaM kinase II; mutation of either of these serines results in upregulated EGFR tyrosine autophosphorylation (10).

$260
100 µl
APPLICATIONS
REACTIVITY
Human

Application Methods: Immunoprecipitation, Western Blotting

Background: P2X purinergic receptors are ATP-gated ion channels involved in physiological processes that include inflammation, afferent sensory signaling, and sympathetic motor nerve activity. Seven different vertebrate genes (P2RX1-P2RX7) encode for individual receptor protein subunits (1). All P2X subunit proteins share similar protein domain structure, but can differ in overall protein length from 384 to 595 amino acids. Each P2X subunit is composed of amino- and carboxy-terminal intracellular domains, two transmembrane domains, and a large extracellular loop that contains ten evenly spaced cysteines and multiple glycosylation sites (2). P2X receptors are found in a variety of cell types and tissues, including central and peripheral nervous system neurons and glial cells, autonomic and sensory neurons, bone, muscle, and hematopoietic tissues (1).

$260
100 µl
APPLICATIONS
REACTIVITY
Human

Application Methods: Immunoprecipitation, Western Blotting

Background: Notch proteins (Notch1-4) are a family of transmembrane receptors that play important roles in development and the determination of cell fate (1). Mature Notch receptors are processed and assembled as heterodimeric proteins, with each dimer comprised of a large extracellular ligand-binding domain, a single-pass transmembrane domain, and a smaller cytoplasmic subunit (Notch intracellular domain, NICD) (2). Binding of Notch receptors to ligands of the Delta-Serrate-Lag2 (DSL) family triggers heterodimer dissociation, exposing the receptors to proteolytic cleavages; these result in release of the NICD, which translocates to the nucleus and activates transcription of downstream target genes (3,4).

$269
100 µl
APPLICATIONS
REACTIVITY
Human, Mouse

Application Methods: Chromatin IP, Immunohistochemistry (Paraffin), Immunoprecipitation, Western Blotting

Background: Although originally identified based on their roles in calcium and bone homeostasis, the vitamin D3 receptor (VDR/NR1I1) and its ligand 1-α, 25-dihydroxycholecalciferol [1α, 25(OH)2D3] are now recognized to exert biological effects in almost every tissue of the human body. Targets for vitamin D signaling include the central nervous system, skin, immune system, endocrine glands, kidney, and colon. At the cellular level, vitamin D signaling affects proliferation, differentiation, and apoptosis of both normal and transformed cells. Within the steroid receptor gene family, VDR belongs to the NR1I subfamily that also includes NR1I2/PXR and NR1I3/CAR. The human VDR gene is composed of 11 exons that encode six domains (A-F) of the full length VDR protein, which includes an N-terminal dual zinc finger DNA binding domain, a C-terminal ligand-binding activity domain, and an extensive unstructured region that links the two functional domains together (1). Upon 1α, 25(OH)2D3 binding to the hormone ligand-binding domain, VDR is stabilized by the phosphorylation of Ser51 in the DNA-binding domain by PKC (2), and Ser208 in the hinge region by casein kinase II (3). VDR associates with the retinoic acid receptor (RXR) through dimerization domains. The 1α, 25(OH)2D3-VDR-RXR complex binds to the vitamin D response elements (VDREs) in the promoters of target genes through the DNA-binding domain. Ligand-induced conformation changes in VDR results in the dissociation of the co-repressor, silencing-mediator for retinoid and thyroid hormone receptors (SMRT), and allows interaction of the VDR activation function (AF2) transactivation domain with transcriptional coactivators (1).Studies have shown that variable VDR expression is associated with different forms or stages of cancer and likely results from tissue-type variation in 1α, 25(OH)2D3 signaling. In the case of colon cancer, research indicates that VDR expression is relatively higher in hyperplastic colon polyps and during early tumorigenesis but diminishes in later stage, poorly differentiated tumors. Multiple studies suggest that 1α, 25(OH)2D3 may be an attractive target for development as a therapeutic anticancer agent (4,5) .

$260
100 µl
APPLICATIONS
REACTIVITY
Human, Monkey, Mouse, Rat

Application Methods: Immunoprecipitation, Western Blotting

Background: Chloride intracellular channel (CLIC) proteins belong to a family of highly conserved transport proteins found as both soluble and membrane-bound forms (1). Although CLIC proteins have putative, selective chloride ion channel activity, they are structural homologs to members of the glutathione-S-transferase protein superfamily and are likewise regulated by redox status (2). CLIC proteins are distinct from other ion channels in that they are found as both soluble and integral membrane forms, and their form determines their function (3-6). Chloride intracellular channel proteins are ubiquitously expressed in numerous tissue types and are involved in diverse biological functions (1,2).

$364
400 µl
This Cell Signaling Technology antibody is immobilized via covalent binding of primary amino groups to N-hydroxysuccinimide (NHS)-activated Sepharose® beads. Phospho-Met (Tyr1234/1235) (D26) XP® Rabbit mAb (Sepharose® Bead Conjugate) is useful for the immunoprecipitation assays.
APPLICATIONS
REACTIVITY
Human, Mouse, Rat

Application Methods: Immunoprecipitation

Background: Met, a high affinity tyrosine kinase receptor for hepatocyte growth factor (HGF, also known as scatter factor) is a disulfide-linked heterodimer made of 45 kDa α- and 145 kDa β-subunits (1,2). The α-subunit and the amino-terminal region of the β-subunit form the extracellular domain. The remainder of the β-chain spans the plasma membrane and contains a cytoplasmic region with tyrosine kinase activity. Interaction of Met with HGF results in autophosphorylation at multiple tyrosines, which recruit several downstream signaling components, including Gab1, c-Cbl, and PI3 kinase (3). These fundamental events are important for all of the biological functions involving Met kinase activity. The addition of a phosphate at cytoplasmic Tyr1003 is essential for Met protein ubiquitination and degradation (4). Phosphorylation at Tyr1234/1235 in the Met kinase domain is critical for kinase activation. Phosphorylation at Tyr1349 in the Met cytoplasmic domain provides a direct binding site for Gab1 (5). Research studies have shown that altered Met levels and/or tyrosine kinase activities are found in several types of tumors, including renal, colon, and breast. Thus, investigators have concluded that Met is an attractive potential cancer therapeutic and diagnostic target (6,7).

$260
100 µl
APPLICATIONS
REACTIVITY
Human, Monkey

Application Methods: Immunoprecipitation, Western Blotting

Background: Met, a high affinity tyrosine kinase receptor for hepatocyte growth factor (HGF, also known as scatter factor) is a disulfide-linked heterodimer made of 45 kDa α- and 145 kDa β-subunits (1,2). The α-subunit and the amino-terminal region of the β-subunit form the extracellular domain. The remainder of the β-chain spans the plasma membrane and contains a cytoplasmic region with tyrosine kinase activity. Interaction of Met with HGF results in autophosphorylation at multiple tyrosines, which recruit several downstream signaling components, including Gab1, c-Cbl, and PI3 kinase (3). These fundamental events are important for all of the biological functions involving Met kinase activity. The addition of a phosphate at cytoplasmic Tyr1003 is essential for Met protein ubiquitination and degradation (4). Phosphorylation at Tyr1234/1235 in the Met kinase domain is critical for kinase activation. Phosphorylation at Tyr1349 in the Met cytoplasmic domain provides a direct binding site for Gab1 (5). Research studies have shown that altered Met levels and/or tyrosine kinase activities are found in several types of tumors, including renal, colon, and breast. Thus, investigators have concluded that Met is an attractive potential cancer therapeutic and diagnostic target (6,7).

$260
100 µl
APPLICATIONS
REACTIVITY
Human

Application Methods: Immunoprecipitation, Western Blotting

Background: Podoplanin (aggrus, glycoprotein 36) is a single-pass transmembrane protein belonging to the type-1 family of sialomucin-like glycoproteins. Podoplanin was first described in the rat as a surface glycoprotein that regulated podocyte morphology (1). It is now commonly used as a marker of lymphatic endothelial cells, where its expression is associated with the process of lymphangiogenesis (2). Its role in this regard is presumably due to its putative involvement in regulating actin cytoskeleton dynamics (3). Research studies have shown that podoplanin expression is upregulated in a number of tumor types including colorectal cancers (4), oral squamous cell carcinomas (5), and germ cell tumors (6), with higher expression levels often associated with more aggressive tumors (7). Research studies have suggested a functional role for podoplanin in the stromal microenvironment of tumors. For example, it has been reported that podoplanin expression in cancer-associated fibroblasts (CAFs) is positively associated with a stromal environment that promotes cancer progression (8,9).

$269
100 µl
APPLICATIONS
REACTIVITY
Hamster, Human, Monkey, Mouse, Rat

Application Methods: Immunohistochemistry (Paraffin), Immunoprecipitation, Western Blotting

Background: YAP (Yes-associated protein, YAP65) was identified based on its ability to associate with the SH3 domain of Yes. It also binds to other SH3 domain-containing proteins such as Nck, Crk, Src, and Abl (1). In addition to the SH3 binding motif, YAP contains a PDZ interaction motif, a coiled-coil domain, and WW domains (2-4). While initial studies of YAP all pointed towards a role in anchoring and targeting to specific subcellular compartments, subsequent studies showed that YAP is a transcriptional co-activator by virtue of its WW domain interacting with the PY motif (PPxY) of the transcription factor PEBP2 and other transcription factors (5). In its capacity as a transcriptional co-activator, YAP is now widely recognized as a central mediator of the Hippo Pathway, which plays a fundamental and widely conserved role in regulating tissue growth and organ size. Phosphorylation at multiple sites (e.g., Ser109, Ser127) by LATS kinases promotes YAP translocation from the nucleus to the cytoplasm, where it is sequestered through association with 14-3-3 proteins (6-8). These LATS-driven phosphorylation events serve to prime YAP for subsequent phosphorylation by CK1δ/ε in an adjacent phosphodegron, triggering proteosomal degradation of YAP (9).

$122
20 µl
$303
100 µl
APPLICATIONS
REACTIVITY
Human, Mouse, Rat

Application Methods: Immunohistochemistry (Paraffin), Immunoprecipitation, Western Blotting

Background: YAP (Yes-associated protein, YAP65) was identified based on its ability to associate with the SH3 domain of Yes. It also binds to other SH3 domain-containing proteins such as Nck, Crk, Src, and Abl (1). In addition to the SH3 binding motif, YAP contains a PDZ interaction motif, a coiled-coil domain, and WW domains (2-4). While initial studies of YAP all pointed towards a role in anchoring and targeting to specific subcellular compartments, subsequent studies showed that YAP is a transcriptional co-activator by virtue of its WW domain interacting with the PY motif (PPxY) of the transcription factor PEBP2 and other transcription factors (5). In its capacity as a transcriptional co-activator, YAP is now widely recognized as a central mediator of the Hippo Pathway, which plays a fundamental and widely conserved role in regulating tissue growth and organ size. Phosphorylation at multiple sites (e.g., Ser109, Ser127) by LATS kinases promotes YAP translocation from the nucleus to the cytoplasm, where it is sequestered through association with 14-3-3 proteins (6-8). These LATS-driven phosphorylation events serve to prime YAP for subsequent phosphorylation by CK1δ/ε in an adjacent phosphodegron, triggering proteosomal degradation of YAP (9).

$260
100 µl
APPLICATIONS
REACTIVITY
Human, Mouse, Rat

Application Methods: Immunoprecipitation, Western Blotting

Background: Cofilin is an evolutionarily conserved, actin-binding protein that severs actin filaments during processes that rely on actin filament dynamics, including cytokinesis, cell migration, invasion, and neuronal development. Actin severing and filament depolymerization are regulated through the controlled cycling of cofilin between the phosphorylated and dephosphorylated forms (1). The kinases LIMK and TESK inactivate cofilin by phosphorylating it at Ser3 (2,3). The slingshot homologs (SSH1, SSH2 and SSH3) and chronophin/PDXP phosphatases remove phosphate from cofilin at Ser3, enabling cofilin binding to actin and filament depolymerization (3). LIMK and SSH1 regulate cofilin activity downstream of neuregulin signaling in Schwann cells (4).Slingshot homolog 1 (SSH1) can also dephosphorylate LIMK kinases, suppressing LIMK phosphorylation of cofilin (5). In addition, SSH1 modulates actin dynamics by stabilizing F-actin and promoting actin bundling independent of its cofilin phosphatase activity (6). SSH1 activity is regulated by phosphorylation and protein-protein interaction through various signaling pathways (1). Binding of SSH1 to F-actin stimulates its cofilin phosphatase activity (7).

$260
100 µl
APPLICATIONS
REACTIVITY
Human

Application Methods: Immunoprecipitation, Western Blotting

Background: Clusterin (CLU, apolipoprotein J) is a multifunctional glycoprotein that is expressed ubiquitously in most tissues. Clusterin functions as a secreted chaperone protein that interacts with and stabilizes stress-induced proteins to prevent their precipitation (1,2). Research studies show that clusterin plays a protective role in Alzheimer’s disease by sequestering amyloid β(1-40) peptides to form long-lived, stable complexes, which prevents amyloid fibril formation (3-5).In addition to the secreted protein, several intracellular isoforms are localized to the nucleus, mitochondria, cytoplasm, and ER. The subcellular distribution of these multiple isoforms leads to the diversity of clusterin functions. Additional studies report that clusterin is involved in membrane recycling, cell adhesion, cell proliferation, apoptosis, and tumor survival (6-9). The clusterin precursor is post-translationally cleaved into the mature clusterin α and clusterin β forms. Clusterin α and β chains create a heterodimer through formation of disulfide bonds (10).

$260
100 µl
$630
300 µl
APPLICATIONS
REACTIVITY
Human, Monkey, Mouse, Rat

Application Methods: Immunoprecipitation, Western Blotting

Background: Met, a high affinity tyrosine kinase receptor for hepatocyte growth factor (HGF, also known as scatter factor) is a disulfide-linked heterodimer made of 45 kDa α- and 145 kDa β-subunits (1,2). The α-subunit and the amino-terminal region of the β-subunit form the extracellular domain. The remainder of the β-chain spans the plasma membrane and contains a cytoplasmic region with tyrosine kinase activity. Interaction of Met with HGF results in autophosphorylation at multiple tyrosines, which recruit several downstream signaling components, including Gab1, c-Cbl, and PI3 kinase (3). These fundamental events are important for all of the biological functions involving Met kinase activity. The addition of a phosphate at cytoplasmic Tyr1003 is essential for Met protein ubiquitination and degradation (4). Phosphorylation at Tyr1234/1235 in the Met kinase domain is critical for kinase activation. Phosphorylation at Tyr1349 in the Met cytoplasmic domain provides a direct binding site for Gab1 (5). Research studies have shown that altered Met levels and/or tyrosine kinase activities are found in several types of tumors, including renal, colon, and breast. Thus, investigators have concluded that Met is an attractive potential cancer therapeutic and diagnostic target (6,7).

$129
20 µl
$303
100 µl
APPLICATIONS
REACTIVITY
Human

Application Methods: Flow Cytometry, IHC-Leica® Bond™, Immunofluorescence (Immunocytochemistry), Immunohistochemistry (Frozen), Immunohistochemistry (Paraffin), Immunoprecipitation, Western Blotting

Background: Met, a high affinity tyrosine kinase receptor for hepatocyte growth factor (HGF, also known as scatter factor) is a disulfide-linked heterodimer made of 45 kDa α- and 145 kDa β-subunits (1,2). The α-subunit and the amino-terminal region of the β-subunit form the extracellular domain. The remainder of the β-chain spans the plasma membrane and contains a cytoplasmic region with tyrosine kinase activity. Interaction of Met with HGF results in autophosphorylation at multiple tyrosines, which recruit several downstream signaling components, including Gab1, c-Cbl, and PI3 kinase (3). These fundamental events are important for all of the biological functions involving Met kinase activity. The addition of a phosphate at cytoplasmic Tyr1003 is essential for Met protein ubiquitination and degradation (4). Phosphorylation at Tyr1234/1235 in the Met kinase domain is critical for kinase activation. Phosphorylation at Tyr1349 in the Met cytoplasmic domain provides a direct binding site for Gab1 (5). Research studies have shown that altered Met levels and/or tyrosine kinase activities are found in several types of tumors, including renal, colon, and breast. Thus, investigators have concluded that Met is an attractive potential cancer therapeutic and diagnostic target (6,7).

$260
100 µl
APPLICATIONS
REACTIVITY
Human, Monkey, Mouse

Application Methods: Immunohistochemistry (Paraffin), Immunoprecipitation, Western Blotting

Background: YAP (Yes-associated protein, YAP65) was identified based on its ability to associate with the SH3 domain of Yes. It also binds to other SH3 domain-containing proteins such as Nck, Crk, Src, and Abl (1). In addition to the SH3 binding motif, YAP contains a PDZ interaction motif, a coiled-coil domain, and WW domains (2-4). While initial studies of YAP all pointed towards a role in anchoring and targeting to specific subcellular compartments, subsequent studies showed that YAP is a transcriptional co-activator by virtue of its WW domain interacting with the PY motif (PPxY) of the transcription factor PEBP2 and other transcription factors (5). In its capacity as a transcriptional co-activator, YAP is now widely recognized as a central mediator of the Hippo Pathway, which plays a fundamental and widely conserved role in regulating tissue growth and organ size. Phosphorylation at multiple sites (e.g., Ser109, Ser127) by LATS kinases promotes YAP translocation from the nucleus to the cytoplasm, where it is sequestered through association with 14-3-3 proteins (6-8). These LATS-driven phosphorylation events serve to prime YAP for subsequent phosphorylation by CK1δ/ε in an adjacent phosphodegron, triggering proteosomal degradation of YAP (9).

$260
100 µl
APPLICATIONS
REACTIVITY
Human, Monkey

Application Methods: Immunoprecipitation, Western Blotting

Background: The adducins (ADD) are cytoskeleton-associated proteins that help cap the ends of actin filaments, promote association between spectrin and actin, and participate in synapse assembly. The three closely related genes ADD1, ADD2, and ADD3 encode the α-adducin, β-adducin, and γ-adducin proteins (1). Research studies indicate that β-adducin is found at high levels in brain and hematopoietic tissues, whereas both α-adducin and γ-adducin are ubiquitously expressed (2). Adducin protein function is regulated by phosphorylation at a number of sites. Both PKA and PKC can phosphorylate α-adducin at Ser726 and β-adducin at Ser713, which inhibits calmodulin binding and adducin activity (3-5). Additionally, PKA (but not PKC) can phosphorylate β-adducin at Ser408, Ser436, and Ser481, which negatively affects spectrin-actin interactions (3). Phosphorylation of α-adducin at Thr445 and Thr480 by Rho-kinase regulates cell motility and membrane ruffling (6). Finally, CDK-1 phosphorylation of α-adducin at Ser12 and Ser355 during mitosis leads to association of α-adducin with the mitotic spindle, suggesting that α-adducin may play a role in mitotic regulation (7). Because α-adducin plays a role in regulating renal sodium reabsorption, it is not surprising that a number of studies show a relationship between ADD1 genetic polymorphisms and the development of hypertension (8-10).

$122
20 µl
$293
100 µl
APPLICATIONS
REACTIVITY
Human

Application Methods: Chromatin IP, Chromatin IP-seq, Flow Cytometry, Immunofluorescence (Immunocytochemistry), Immunoprecipitation, Western Blotting

Background: PR domain zinc finger protein 14 (PRDM14) is a likely protein lysine methyltransferase that is primarily expressed in primordial germ cells and pluripotent embryonic stem cells. It is essential for the establishment and maintenance of primordial germ cells and critical for the maintenance of pluripotency in embryonic stem cells (1-3). PRDM14 represses genes involved in the differentiation of stem cells into various cell lineages, likely via a combination of interactions with TET proteins, the polycomb repressive complex 2 (PRC2), and CBFA2T2 (3-8). In addition, overexpression of PRDM14 in combination with Jarid2 promotes induced pluripotent stem cell (iPSC) formation (9). PRDM14 protein levels are overexpressed in certain cancers, including breast, leukemia (T-ALL), and non-small cell lung cancer (NSCLC) (10-13), and PRDM14 overexpression may serve as a novel prognostic marker in NSCLC (14). Targeting PRDM14 overexpression with a siRNA-based therapy was shown to decrease liver metastasis in a murine pancreatic cancer model, suggesting potential as a therapeutic option for cancers where this protein is abnormally expressed (15).

$260
100 µl
APPLICATIONS
REACTIVITY
Human

Application Methods: Chromatin IP, Chromatin IP-seq, Immunoprecipitation, Western Blotting

Background: PR domain zinc finger protein 14 (PRDM14) is a likely protein lysine methyltransferase that is primarily expressed in primordial germ cells and pluripotent embryonic stem cells. It is essential for the establishment and maintenance of primordial germ cells and critical for the maintenance of pluripotency in embryonic stem cells (1-3). PRDM14 represses genes involved in the differentiation of stem cells into various cell lineages, likely via a combination of interactions with TET proteins, the polycomb repressive complex 2 (PRC2), and CBFA2T2 (3-8). In addition, overexpression of PRDM14 in combination with Jarid2 promotes induced pluripotent stem cell (iPSC) formation (9). PRDM14 protein levels are overexpressed in certain cancers, including breast, leukemia (T-ALL), and non-small cell lung cancer (NSCLC) (10-13), and PRDM14 overexpression may serve as a novel prognostic marker in NSCLC (14). Targeting PRDM14 overexpression with a siRNA-based therapy was shown to decrease liver metastasis in a murine pancreatic cancer model, suggesting potential as a therapeutic option for cancers where this protein is abnormally expressed (15).

$134
20 µl
$336
100 µl
APPLICATIONS
REACTIVITY
Human, Mouse, Rat

Application Methods: Flow Cytometry, Immunofluorescence (Immunocytochemistry), Immunohistochemistry (Frozen), Immunohistochemistry (Paraffin), Immunoprecipitation, Western Blotting

Background: Met, a high affinity tyrosine kinase receptor for hepatocyte growth factor (HGF, also known as scatter factor) is a disulfide-linked heterodimer made of 45 kDa α- and 145 kDa β-subunits (1,2). The α-subunit and the amino-terminal region of the β-subunit form the extracellular domain. The remainder of the β-chain spans the plasma membrane and contains a cytoplasmic region with tyrosine kinase activity. Interaction of Met with HGF results in autophosphorylation at multiple tyrosines, which recruit several downstream signaling components, including Gab1, c-Cbl, and PI3 kinase (3). These fundamental events are important for all of the biological functions involving Met kinase activity. The addition of a phosphate at cytoplasmic Tyr1003 is essential for Met protein ubiquitination and degradation (4). Phosphorylation at Tyr1234/1235 in the Met kinase domain is critical for kinase activation. Phosphorylation at Tyr1349 in the Met cytoplasmic domain provides a direct binding site for Gab1 (5). Research studies have shown that altered Met levels and/or tyrosine kinase activities are found in several types of tumors, including renal, colon, and breast. Thus, investigators have concluded that Met is an attractive potential cancer therapeutic and diagnostic target (6,7).