Video Experimental Relacionado
Updated: Jul 17, 2026
12:24
Mimicking the Function of Signaling Proteins: Toward Artificial Signal Transduction Therapy
Published on: September 29, 2016
Dominios SH2 y SH3: elementos que controlan las interacciones de las proteínas de señalización del citoplasma
C A Koch1, D Anderson, M F Moran
1Division of Molecular and Developmental Biology, Samuel Lunenfeld Research Institute, Mount Sinai Hospital, Toronto, Ontario, Canada.
Science (New York, N.Y.)
|May 3, 1991
Resumen
Los dominios 2 y 3 de homología Src (SH) son cruciales para la señalización celular al vincular las tirosinacinasas a las proteínas diana. Estos dominios no catalíticos median la formación de complejos proteicos, controlando las respuestas intracelulares a los factores de crecimiento.
Área de la Ciencia:
- La señalización celular de las células.
- Biología molecular La biología molecular.
- La bioquímica es la bioquímica.
Sus antecedentes:
- Las regiones 2 y 3 de homología Src (SH) son dominios no catalíticos conservados en las proteínas de señalización citoplasmáticas.
- Estos dominios están regulados por las proteínas receptoras tirosina quinasa y están involucrados en vías como la activación de la fosfolipasa C-gamma y Ras GTPasa.
- Los dominios SH2 se unen a los polipéptidos fosforilados de tirosina, cruciales para la señalización normal y la transformación celular.
Objetivo del estudio:
- Para aclarar el papel de los dominios SH2 y SH3 en las vías de señalización de la proteína-tirosina quinasa.
- Comprender cómo estos dominios median la formación de complejos proteicos y controlan las respuestas intracelulares.
- Explorar la función de las proteínas no catalíticas que contienen los dominios SH2 y SH3 como adaptadores.
Principales métodos:
- Análisis de los dominios proteicos conservados (SH2 y SH3) en las proteínas de señalización citoplasmáticas.
- Investigación de la fosforilación de la tirosina como interruptor para la unión al dominio SH2.
- Examen de la formación de complejos de proteínas heteroméricas en la membrana plasmática.
Principales resultados:
- Los dominios SH2 se unen a los polipéptidos fosforilados de tirosina, mediando la formación de complejos heteroméricos.
- Los dominios SH3, junto con SH2, modulan las interacciones con el citoesqueleto y la membrana.
- Las proteínas no catalíticas con dominios SH2 y SH3 actúan como adaptadores, vinculando las tirosinacinasas a las proteínas diana.
Conclusiones:
- Los dominios SH2 y SH3 son reguladores clave de las respuestas intracelulares a la estimulación del factor de crecimiento.
- La formación de complejos proteicos mediados por los dominios SH2 controla las vías de transducción de señales.
- Las proteínas adaptadoras no catalíticas juegan un papel importante en la transducción de señales por las tirosinacinasas.
Videos de Conceptos Relacionados
01:28Yeast Signaling
Yeasts are single-celled organisms, but unlike bacteria, they are eukaryotes (cells with a nucleus). Cell signaling in yeast is similar to signaling in other eukaryotic cells. A ligand, such as a protein or a small molecule released from a yeast cell, attaches to a receptor on the cell surface. The binding stimulates second-messenger kinases to activate or inactivate transcription factors that further regulate gene expression. Many of the yeast intracellular signaling cascades have similar...
02:26Conservation of Protein Domains Over Different Proteins
Protein domains are small structurally independent units that are part of a single amino acid chain. Although these domains are often structurally independent, they may rely on synergistic effects to perform their functions as part of a larger protein. Protein domains may be conserved within the same organism, as well as across different organisms.
A limited set of protein domains often duplicate and recombine during evolution. These domains can be organized in different combinations to form...
A limited set of protein domains often duplicate and recombine during evolution. These domains can be organized in different combinations to form...
01:30Assembly of Signaling Complexes
Multiprotein signaling complexes are formed in a dynamic process involving protein-protein interactions at the cytoplasmic domain of transmembrane receptors or enzymatic and non-enzymatic proteins associated with the receptor. These complexes ensure the activation and propagation of intracellular signals that regulate cell functions.
Interaction domains in cell signaling
Interaction domains recognize exposed features of their binding partners containing post-translationally modified sequences,...
Interaction domains in cell signaling
Interaction domains recognize exposed features of their binding partners containing post-translationally modified sequences,...
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...
01:20The 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...
01:17Intracellular Signaling Affects Focal Adhesions
Integrins act both as extracellular input receivers and as intracellular processing activators. As their name suggests, integrins are entirely integrated into the membrane structure. Their hydrophobic membrane-spanning regions interact with the phospholipid bilayer's hydrophobic region. These membrane receptors provide extracellular attachment sites for effectors like hormones and growth factors. They activate intracellular response cascades when their effectors are bound and active.
Some...
Some...