Flashcard: Cell Cytoskeleton Fundamentals — 22 carte

Cytoskeleton functions — support?

Provides cell shape and internal organization.

Protein filament types — number?

Three: intermediate filaments, microtubules, actin filaments.

Intermediate filaments — structure?

Rope-like, strong, composed of twisted protein strands.

Nuclear lamina — made of?

Lamins, supporting nuclear envelope.

Mutations in lamins — cause?

Progeria, a premature aging disorder.

Cytoskeleton-nucleus links — proteins?

Plectin, SUN, and KASH proteins.

Microtubules — structure?

Hollow tubes of tubulin with plus/minus ends.

Microtubules — organizing center?

Centrosome with γ-tubulin rings.

Microtubules — dynamics?

GTP hydrolysis drives growth and shrinkage.

Microtubules — in cell?

Organize interior, guide transport, form spindles.

Actin filaments — properties?

Thin, flexible, polymerize via ATP.

Actin — role in movement?

Form protrusions, interact with myosin for motility.

Actin protrusions — types?

Lamellipodia and filopodia.

Actin treadmilling — process?

Addition at plus end, disassembly at minus end.

Intermediate filaments — assembly?

Monomers form dimers, tetramers, then filaments.

Nuclear lamina — function?

Supports nuclear envelope, attaches chromosomes.

Linker proteins — examples?

Plectin, SUN, KASH.

Microtubule ends — stability?

Plus ends grow, minus ends often anchored.

Drugs affecting microtubules — examples?

Taxol (stabilizes), colchicine, vinblastine (prevent polymerization).

Actin in cell interior — function?

Cell shape, protrusions, migration.

Microtubules — composition?

Tubulin α/β dimers.

Actin — polymerization?

Driven by extracellular signals at the plus end.