Cell Signaling Flashcards

Vocabulary flashcards for reviewing cell signaling lecture notes.

Gs protein

A member of the G protein family that stimulates adenylate cyclase, leading to the production of cAMP.

Adenylate cyclase

An enzyme that catalyzes the conversion of ATP to cAMP.

cAMP

A secondary messenger that diffuses freely in the cytoplasm and binds to protein kinase A (PKA), thereby activating it.

Protein kinase A (PKA)

An enzyme that phosphorylates various target proteins, including ion channels, influencing their activity.

Phosphodiesterase

An enzyme that breaks down cAMP, terminating the signal.

CREB (CRE-binding protein)

Transcription factor phosphorylated by activated PKA, which then binds to CBP, activating RNA polymerase II.

CBP (CREB-binding protein)

Binds to phosphorylated CREB, thereby activating RNA polymerase II and leading to downstream gene expression changes.

Phospholipase C (PLC)

An enzyme that cleaves PIP2, generating DAG and IP3.

Phosphatidylinositol-4,5-bisphosphate (PIP2)

A minor phospholipid in the inner leaflet of the plasma membrane, cleaved by phospholipase C to generate DAG and IP3.

Diacylglycerol (DAG)

A hydrophobic molecule that diffuses within the lipid membrane and activates protein kinase C (PKC).

Inositol-1,4,5-trisphosphate (IP3)

A water-soluble molecule that diffuses in the cytosol and binds to the IP3 receptor, causing calcium channels to open.

IP3 receptor

An IP3-gated calcium channel located in the membrane of the smooth endoplasmic reticulum (SER).

Calmodulin (CaM)

A calcium-binding protein that activates various enzymes, including calcium/calmodulin-dependent protein kinase II (CaMKII).

Mitogen-activated protein (MAP) kinase

A serine/threonine-specific protein kinase that responds to extracellular stimuli and regulates various cellular activities.

Adaptors

Proteins recruited by the activated receptor tyrosine kinase (RTK) that help to form a large signaling complex.

Ras

A small GTP-binding protein anchored to the plasma membrane that initiates a phosphorylation cascade.

JAKs (Janus kinases)

Cytoplasmic tyrosine kinases that become activated when a cytokine binds to its receptor.

STATs (signal transducers and activators of transcription)

Cytoplasmic gene regulatory proteins that are phosphorylated and activated by JAKs and then migrate to the nucleus.

Interferons

Cytokines that instruct cells to produce proteins that enhance their resistance to viral infections.

TGF-β

Hormones and local mediators that activate serine/threonine kinases receptors and belong to the TGF-β (transforming growth factor-beta) superfamily.

SMADs

Cytoplasmic gene regulatory proteins that are directly phosphorylated and activated by serine/threonine kinases receptors.

NF-κB

Proteins present in most animal cells that play a central role in stress responses, inflammation, and innate immunity.

Tumor necrosis factor α (TNFα)

Cytokines that are crucial for inflammatory responses and activate the NF-κB signaling pathway.

IκB kinase (IKK)

A serine/threonine protein kinase that phosphorylates and activates IκB kinase (IKK).

IκB

Inhibitory protein that binds to NF-κB, keeping it inactive in the cytoplasm.

Sonic hedgehog (SHH)

Binds to Patched-1 receptor, relieving SMO inhibition, leading to activation of GLI transcription factors.

Delta

Expressed on the surface of future nerve cells and binds to Notch receptor proteins on neighboring cells.

Insulin signaling

Signal promotes glucose transport proteins to the plasma membrane, altering glucose uptake rates.

Hyperglycemia

High blood sugar levels

Retinal

Undergo photo-isomerization which activates the rhodopsin.

Apoptosis

Carried out by caspases.

Necrosis

A mode of cell death that occurs when cells are exposed to extreme variance.

IAP

Inactivates caspases.

Cyclin-dependent kinases

Protein kinases that are required for cell cycle progression.

Phylogenetic Tree

Shows evolutionary relationships.

Molecular clock

estimator of events= assumes mutations overtime

Microsatellites

Short tandem repeats, 2-6 pairs, telomeres and telomerase

Linkage groups

A set of genes inherited together cuz they on the same gene.

Genetic maps

Shows locations of genes on chromosome and recombination frequency.

DNA

Double helix= alternating deoxyribose and phosphate grps, 4 nucleotides paired as AT 2 H-bonds, GC 3 H-bonds, oppo strands of 3' to 5' and 5' to 3'

Telomere

The one at the ends repeated, involved with aging.

Transposons

Jumping genes for diversity/evolution& gene regulation

DNA Transposons

Cut&paste= removed from somewhere and inserted somewhere else

Retrotransposons

Copy and paste= transcribed into RNA and reverse transcribed back in DNA

tRNA (transfer RNA)

Brings the amino acids, has anticodon for codon

rRNA (ribosomal RNA)

Combines proteins, checks t&m and watches enzymes needed for peptide bonds