cell signaling

may 16

target cells

cell that has specific receptors for a particular signaling molecule

receptor proteins

specialized proteins that bind specific signaling molecules

ligands

molecule that binds specifically to a receptor to trigger a response

second messengers

Second messengers are small intracellular signaling molecules that are produced or released in response to ligand-receptor binding. They help amplify and spread the signal inside the cell, leading to a specific cellular response.

local communication

communication that occurs over very short distances

gap junctions

proteins that connect the cytoplasms of adjacent cells, which is good for electrical and chemical signals

contact-dependent signals

binding between surface molecules and receptor proteins

paracrine signals

act on neighboring cells

autocrine signals

act on cell that secreted them, aka itself

long-distance communication

takes place through the endocrine and nervous systmes

potential

difference in charge across a membrane

resting

when the cell is not firing an action potential

hormones

long distance communication by the endocrine system that is secreted into the blood to be carried into the body

neurocrine molecules

an electrical signal that is converted into a chemical signal

neurotransmitters

a form of long distance communication by the nervous system that travels short distances and have rapid effects

neurohormones

a form of long distance communication by the nervous system that is released into the blood and circulate throughout the body

lipophillic

a type of ligand that diffuses through the cell membrane and binds to receptors inside the target cell

lipophobic

a type of ligand that remains in the EFC and binds to receptors on the surface of the target cell

receptor channel

a ligand binding that opens or closes the channel

G-protein coupled receptor

a ligand binding to a G protein-coupled receptor to open an ion channel or alter enzyme activity

receptor-enzyme

a catalytic receptor whose ligand binds to a receptor-enzyme to activate an intracellular enzyme

integrin receptor

a catalytic response whose ligand binds to a integrin receptor to alter enzymes or the cytoskeleton

signaling cascade

a process of signal transduction that causes sequential enzyme activation

kinase

a type of enzyme that transfers phosphate groups from ATP to a protein

GDP/GTP

part of the G protein. G protein is inactive when bound to GDP and active when bound to GTP

adenylyl cyclase

an amplifier enzyme that converts ATP to cAMP

cAMP

stands for cyclic AMP, which activates kinases during a GPCR-cAMP pathway

PLC

stands for phospholipase C, which is an amplifier enzyme that converts membrane phospholipids into DAG during a GPCR-Phospholipase C pathway

IP₃

otherwise known as ionsitol triphosphate, which causes Calcium to be released from the ER to cause a cellular response

agonist

binds and activates just like the primary ligand

antagonist

binds and blocks receptor activity

isoforms

different forms of the same protein

up/down regulation

either an increase or decrease in receptor number

desensitization

binding a chemical modulator to the receptor, which is usually phosphorylation