Cell Signaling and Communication

Flashcards covering key concepts, definitions, and terms related to cell signaling and communication.

tyrosine kinase receptor

A type of protein receptor that, when bound by a ligand, activates tyrosine kinase activity leading to signal transduction.

JAK STAT pathway

A signaling pathway activated by cytokines, which leads to the transcription of target genes.

G Protein Coupled Receptors (GPCRs)

Membrane-bound receptors that activate G-proteins upon ligand binding, playing crucial roles in signal transduction.

ligand-gated ion channel

A membrane protein that allows specific ions to pass through in response to the binding of a ligand.

phosphorylation cascade

A series of enzymatic reactions whereby a protein activates another by adding a phosphate group.

secondary messengers

Small molecules that relay signals received by cell surface receptors to target molecules within the cell.

cAMP (cyclic adenosine monophosphate)

A common secondary messenger involved in many biological processes, activating protein kinase A (PKA).

calcium ions (Ca2+)

A versatile second messenger that plays critical roles in signal transduction pathways, particularly in muscle contraction.

autocrine signaling

A type of cell signaling where the signaling cell also responds to its own signal.

paracrine signaling

Cell signaling where the signal acts on nearby target cells.

endocrine signaling

Long-distance signaling where hormones are secreted into the bloodstream to act on distant target cells.

GTPase activity

The ability of G-proteins to hydrolyze GTP to GDP, a mechanism that turns off the signaling pathway.

phosphatases

Enzymes that remove phosphate groups from proteins, often reversing the actions of kinases.

ligand

A signaling molecule that binds specifically to a protein to elicit a response.

ionotropic receptors

Membrane proteins that form ion channels which open or close in response to the binding of ligands.

adrenaline (epinephrine)

A hormone that triggers a 'fight or flight' response, often acting through GPCRs and cAMP pathways.

glycogen phosphorylase

An enzyme that breaks down glycogen into glucose-1-phosphate in response to adrenaline.

ACE2

Angiotensin-converting enzyme 2, a receptor that serves as a point of entry for SARS-CoV-2 into cells.