Sect 10 Quiz Easy

The process of converting extracellular signals into cellular responses.

A series of steps that converts a signal from outside the cell to a specific cellular response.

The specific binding of a signaling molecule (ligand) to a receptor protein on the cell surface or within the cell.

A transmembrane receptor that works with a G protein to initiate a signal transduction pathway.

Receptors that have enzymatic activity, specifically tyrosine kinase activity, which phosphorylates tyrosines on intracellular domains when activated by a ligand.

A small molecule or ion inside a cell that relays a signal from a receptor to other intracellular signaling proteins, amplifying the signal.

An enzyme that catalyzes the transfer of phosphate groups from ATP to a specific protein.

An enzyme that removes phosphate groups from proteins.

The changes in cell metabolism, function, movement, or gene expression in response to a signal.

The increase in the strength of a signal as it moves through the transduction pathway.

Proteins located on cell surfaces or inside cells (cytosol/nucleus) that bind to specific ligands, triggering cellular responses.

Receptors bind to specific ligands based on the shape and chemical properties of both.

Receptors activate particular signaling pathways, leading to specific cellular responses.

The concentration of ligand required for half of the receptors to be bound. A lower Kd indicates stronger binding.

Intracellular signaling molecules that amplify and relay signals from cell surface receptors to target molecules inside the cell.

Enzymatic cascades in signaling pathways increase the strength of a signal.

Proteins that act as molecular switches, turning on or off cellular signals based on their GTP or GDP binding states.

The process of converting signals received at the cell surface into cellular responses.

A cell-surface receptor with seven membrane-spanning domains that transduces signals from the external environment to intracellular pathways.

A protein complex composed of three subunits (α, β, γ) that acts as a molecular switch, relaying signals from GPCRs to effector proteins.

The GTP-binding subunit of a trimeric G protein; its active state is GTP-bound.

A protein, such as adenylyl cyclase, that directly affects the intracellular response to a G protein signal.

A second messenger commonly generated in GPCR pathways. Increases cAMP; enzyme adenylyl cyclase activates GPCRs

An enzyme activated by certain G protein that catalyzes cAMP synthesis.

A small molecule, such as cAMP, that mediates the relaying of a signal from the cell surface to the interior of the cell.

Gas protein, a G-protein, loses its GTP, becoming inactive, thus reducing adenylate cyclase activity.

Adenylate cyclase accelerates Gas's intrinsic GTPase activity, leading to Gas inactivation.

cAMP phosphodiesterase breaks down cAMP, ending cell response to a signal.

The process of reducing cell surface receptors to decrease cell sensitivity to hormones.

BARK phosphorylates activated GPCRs, leading to b-arrestin binding and endocytosis.

b-arrestin blocks GPCR interaction with Gs, inhibiting further signal transduction.

PKA phosphorylates CREB, enabling CREB to bind to DNA.

Phosphorylated CREB interacts with CBP/P300 to stimulate target gene transcription.

GPCR-arrestin complex activates other cytosolic kinases like c-Src, triggering signaling cascades.

Anchoring proteins localize cAMP effects to specific subcellular areas.

A cell-to-cell signaling pathway where a protein called Notch is cleaved and then translocates to the nucleus to control gene expression.

A protein that acts as a ligand (signal) in Notch signaling, binding to Notch to initiate the signal.

Enzyme complex that cleaves Notch; vital for Notch signaling.

A process marking proteins for degradation; often plays a role in signaling pathways like Wnt.

A signaling pathway regulating development and cell fate, involves beta-catenin.

A transcription factor in the Wnt pathway; its presence/absence determines transcription.

A receptor for Wnt signaling that works with LRP to initiate intracellular signaling cascade.

Wnt proteins are anchored to cell membranes by a lipid, limiting their range of influence.

A signaling pathway that controls cell growth and development by stabilizing a transcription factor (b-catenin).

Ubiquitination and degradation of b-catenin by E3 ligase (TrCP) in response to Wnt absence.

Causes LRP phosphorylation leading to Axin binding and b-catenin stabilization.

Prevent b-catenin phosphorylation by disrupting the Axin complex, leading to its accumulation.

b-catenin moves to the nucleus after stabilization to bind TCF and activate gene transcription.

Hedgehog signaling involves Smo, Ptc, and Ci in a cascade leading to transcriptional changes.

Hedgehog precursor undergoes proteolytic cleavage and post-translational modifications (cholesterol, palmitoyl) before activation.

Post-translational modifications like palmitoylation anchor Hh to cell membrane.

Ptc inhibits Smo in the absence of Hedgehog, Smo is active and regulates cellular responses upon Hedgehog interaction.

Hedgehog binding leads to an activating form of Ci, which translocates to the nucleus and activates gene expression.