Video Experimental Relacionado
Updated: Aug 9, 2026
08:05
Assaying Protein Kinase Activity with Radiolabeled ATP
Published on: May 26, 2017
La activación de Pyk2 por señales de estrés y acoplamiento con la vía de señalización JNK
1Department of Pharmacology, New York University Medical Center, 550 First Avenue, New York, NY 10016, USA.
Science (New York, N.Y.)
|August 9, 1996
Resumen
La tirosina quinasa Pyk2 actúa como un mediador sensible al estrés, vinculando las señales extracelulares a la vía de la c-Jun amino-terminal quinasa (JNK). La activación de Pyk2 por estímulos de estrés conduce a la activación de la JNK, revelando un nuevo enlace de señalización.
Área de la Ciencia:
- Las vías de señalización celular.
- Mecanismos de respuesta al estrés.
- Investigación de la proteína quinasa en la investigación de la proteína quinasa.
Sus antecedentes:
- La vía de la c-Jun amino-terminal quinasa (JNK) es activada por los receptores acoplados a la proteína G, las citoquinas inflamatorias y el estrés.
- Los mediadores aguas arriba que conectan las señales extracelulares a la activación de JNK siguen siendo en gran medida desconocidos.
Objetivo del estudio:
- Para identificar los mediadores aguas arriba que vinculan las señales de estrés extracelular a la vía de señalización JNK.
- Para investigar el papel de la tirosina quinasa Pyk2 en la activación del JNK.
Principales métodos:
- La activación de Pyk2 por el factor de necrosis tumoral alfa, la irradiación ultravioleta y los cambios osmóticos.
- Evaluación de la activación de JNK después de la sobreexpresión de Pyk2.
- Utilizando un mutante Pyk2 negativo dominante para bloquear la activación del JNK.
Principales resultados:
- La Pyk2 tirosina quinasa se activa por varios estímulos de estrés, incluido el TNF-alfa, la irradiación UV y los cambios en la osmolaridad.
- La sobreexpresión de Pyk2 resulta en la activación de la vía JNK.
- Un mutante Pyk2 negativo dominante inhibe la activación de JNK inducida por el choque osmótico y UV.
Conclusiones:
- Pyk2 sirve como un mediador novedoso, específico para el tipo de célula y sensible al estrés en la vía de señalización JNK.
- Pyk2 une las señales de estrés extracelular con la activación intracelular del JNK.
Videos de Conceptos Relacionados
01:19Interactions Between Signaling Pathways
Signaling cascades usually lack linearity. Multiple pathways interact and regulate one another, allowing cells to integrate and respond to diverse environmental stimuli.
Convergence and divergence, and cross-talk between signaling pathways
Two distinct signaling pathways can converge on a single functional unit, which may either be a single protein or a complex of proteins. The response is either functionally distinct or synergistic between the two pathways but different from the response...
Convergence and divergence, and cross-talk between signaling pathways
Two distinct signaling pathways can converge on a single functional unit, which may either be a single protein or a complex of proteins. The response is either functionally distinct or synergistic between the two pathways but different from the response...
01:22Amplifying Signals via Enzymatic Cascade
When a ligand binds to a cell-surface receptor, the receptor's intracellular domain changes shape, which may either activate its enzyme function or allow its binding to other molecules. The initial signal is amplified by most signal transduction pathways. This means that a single ligand molecule can activate multiple molecules of a downstream target. Proteins that relay a signal are most commonly phosphorylated at one or more sites, activating or inactivating the protein. Kinases catalyze the...
01:07MAPK Signaling Cascades
Mitogen-activated protein kinase, or MAPK pathway, activates three sequential kinases to regulate cellular responses such as proliferation, differentiation, survival, and apoptosis. The canonical MAPK pathway starts with a mitogen or growth factor binding to an RTK. The activated RTKs stimulate Ras, which recruits Raf or MAP3 Kinase (MAPKKK), the first kinase of the MAPK signaling cascade. Raf further phosphorylates and activates MEK or MAP2 Kinases (MAPKK), which in turn phosphorylates MAP...
01:20The JAK-STAT Signaling Pathway
Several cytokine receptors have tightly bound Janus kinase or JAK proteins attached at their cytosolic tail. Small signaling molecules such as cytokines, growth hormones, or prolactins bind to the cytokine receptors and initiate their dimerization. The dimerization brings the cytosolic JAKs together that trans-phosphorylate and activates each other. The activated JAKs now phosphorylate cytosolic tails of the cytokine receptors, which serve as binding sites for adaptor proteins such as SH2...
01:22PI3K/mTOR/AKT Signaling Pathway
The mammalian target of rapamycin (mTOR) is a serine/threonine kinase that regulates growth, proliferation, and cell survival in response to hormones, growth factors, or nutrient availability. This kinase exists in two structurally and functionally distinct forms: mTOR complex 1 (mTORC1) and mTOR complex 2 (mTORC2). The first form (mTORC1) is composed of a rapamycin-sensitive Raptor and proline-rich Akt substrate, PRAS40. In contrast, mTORC2 consists of a rapamycin-insensitive companion...
01:25cAMP-dependent Protein Kinase Pathways
Cyclic Adenosine Monophosphate (cAMP) is an essential second messenger that activates protein kinase A (PKA) and regulates various biological processes. A single epinephrine molecule binds to GPCR and activates several heterotrimeric G proteins, each stimulating multiple adenylyl cyclase, amplifying the signal, and synthesizing large numbers of cAMP molecules. Small changes in cAMP concentration affect PKA activity. The binding of four cAMP molecules induces a conformational change in PKA,...