signaling cascade

(noun)

the chain of events that conveys the signal through the cell

Related Terms

Examples of signaling cascade in the following topics:

  • Termination of the Signal Cascade

    • Signal cascades convey signals to the cell through the phosphorylation of molecules by kinases.
    • The chain of events that conveys the signal through the cell is called a signaling pathway or cascade.
    • A major component of cell signaling cascades is the phosphorylation of molecules by enzymes known as kinases.
    • Inside the cell, many different enzymes reverse the cellular modifications that result from signaling cascades.
    • Describe the process by which the signal cascade in cell communication is terminated

  • Signaling in Yeast

    • Yeasts utilize cell-surface receptors, mating factors, and signaling cascades in order to communicate.
    • The components and processes found in yeast signals are similar to those of cell-surface receptor signals in multicellular organisms.
    • When mating factor binds to cell-surface receptors in other yeast cells that are nearby, they stop their normal growth cycles and initiate a cell signaling cascade that includes protein kinases and GTP-binding proteins that are similar to G-proteins.
    • Because yeasts contain many of the same classes of signaling proteins as humans, these organisms are ideal for studying signaling cascades.
    • Therefore, the signaling cascades are also simpler and easier to study, although they contain similar counterparts to human signaling

  • Binding Initiates a Signaling Pathway

    • Ligand binding to cell-surface receptors activates the receptor's intracellular components setting off a signaling pathway or cascade.
    • After the ligand binds to the cell-surface receptor, the activation of the receptor's intracellular components sets off a chain of events that is called a signaling pathway or a signaling cascade .
    • The effects of extracellular signals can also be amplified by enzymatic cascades.
    • However, activation of a receptor-linked enzyme can activate many copies of a component of the signaling cascade, which amplifies the signal.
    • A complex cascade of downstream events causes the cell to grow and divide.

  • Synaptic Plasticity

    • Next, Ca2+ ions entering the cell initiate a signaling cascade that causes a different type of glutamate receptor, AMPA (α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid) receptors, to be inserted into the postsynaptic membrane.
    • In this situation, calcium that enters through NMDA receptors initiates a different signaling cascade, which results in the removal of AMPA receptors from the postsynaptic membrane .
    • This stimulation causes a calcium- and CaMKII-dependent cellular cascade, which results in the insertion of more AMPA receptors into the postsynaptic membrane.
    • The calcium that does flow through NMDA receptors initiates a different calcineurin and protein phosphatase 1-dependent cascade, which results in the endocytosis of AMPA receptors.

  • Cell Signaling and Cell Death

    • External signaling can also initiate apoptosis.
    • The binding of cellular receptors to the extracellular matrix initiates a signaling cascade within the cell.
    • However, if the cell moves away from the extracellular matrix, the signaling ceases, and the cell undergoes apoptosis.
    • Another example of external signaling that leads to apoptosis occurs in T-cell development.
    • A cell signaling mechanism triggers apoptosis, which destroys the cells between the developing digits.

  • Gene Expression for Spatial Positioning

    • During development it is critical that specific gene expression patterns are established to signal and differentiate the cells appropriately.
    • The process of differentiation is regulated by cellular signaling cascades.
    • During the formation of the neural system, special signaling molecules called growth factors signal some cells at the edge of the ectoderm to become epidermis cells.
    • If the signaling by growth factors were disrupted, then the entire ectoderm would differentiate into neural tissue.

  • Organogenesis

    • Therefore, the process of differentiation is regulated by cellular signaling cascades.
    • During the formation of the neural system, special signaling molecules called growth factors signal some cells at the edge of the ectoderm to become epidermis cells.
    • If the signaling by growth factors were disrupted, then the entire ectoderm would differentiate into neural tissue.

  • Programmed Cell Death

    • Apoptosis can also be initiated via external signaling.
    • The binding of cellular receptors to the extracellular matrix initiates a signaling cascade within the cell.
    • However, if the cell moves away from the extracellular matrix, the signaling ceases, and the cell undergoes apoptosis.
    • Another example of external signaling that leads to apoptosis occurs in T-cell development.
    • A cell signaling mechanism triggers apoptosis, which destroys the cells between the developing digits.

  • Methods of Intracellular Signaling

    • The induction of a signaling pathway depends on the modification of a cellular component by an enzyme.
    • Phosphorylation of tyrosine residues can either affect the activity of an enzyme or create a binding site that interacts with downstream components in the signaling cascade.
    • They are small molecules that propagate a signal after it has been initiated by the binding of the signaling molecule to the receptor.
    • Phosphatidylinositol (PI) is the main phospholipid that plays a role in cellular signaling.
    • Explain how the binding of a ligand initiates signal transduction throughout a cell

  • How Hormones Work

    • Hormones are chemical messengers that relay messages to cells that display specific receptors for each hormone and respond to the signal.
    • In essence, it is a chemical messenger that transports a signal from one cell to another.
    • The hormone binds to the receptor protein, resulting in the activation of a signal transduction mechanism that ultimately leads to cell type-specific responses.
    • Depending on the location of the protein receptor on the target cell and the chemical structure of the hormone, hormones can mediate changes directly by binding to intracellular hormone receptors and modulating gene transcription, or indirectly by binding to cell surface receptors and stimulating signaling pathways.
    • The hormone insulin binds to its receptor (1), which starts many protein activation cascades (2).