Intracellular Compartments and Protein Transport

These flashcards cover key terms and concepts related to intracellular compartments and protein transport, drawn from the lecture on cell biology.

Adaptin

A protein that facilitates the transport of cargo in clathrin-coated vesicles.

Autophagy

The process by which a cell degrades and recycles its own components.

Chloroplast

An organelle in plant cells that conducts photosynthesis.

Clathrin-coated vesicles

Transport vesicles that are formed via a protein coat made from clathrin.

Cytoplasm

The jelly-like fluid inside a cell, excluding the nucleus.

Cytosol

The fluid component of the cytoplasm, in which organelles are suspended.

Endocytosis

The process by which cells internalize substances from their environment.

Endomembrane system

A group of membranes and organelles in eukaryotic cells that work together to modify, package, and transport lipids and proteins.

Endoplasmic reticulum (ER)

An organelle that synthesizes proteins and lipid molecules.

Endosome

A membrane-bound compartment inside eukaryotic cells that serves as a sorting station for endocytosed material.

Exocytosis

The process of exporting materials out of the cell by vesicle fusion with the plasma membrane.

Glycogen

A storage form of glucose in liver and muscle cells.

Golgi apparatus

An organelle responsible for modifying, sorting, and shipping proteins and lipids.

GTP

Guanosine triphosphate, a molecule that provides energy for many cellular processes.

Hepatocyte

A liver cell.

Lysosome

An organelle that contains digestive enzymes to breakdown waste materials and cellular debris.

Mitochondria

Organelle known as the powerhouse of the cell, generating ATP through respiration.

Nuclear pore

Large protein complexes that cross the nuclear envelope and regulate the transport of molecules in and out of the nucleus.

Nucleus

Membrane-bound organelle that contains the cell's genetic material.

Peroxisome

An organelle that contains enzymes for metabolism of fatty acids and the detoxification of hydrogen peroxide.

Phagocytosis

A cellular process of engulfing and digesting large particles, such as pathogens.

Pinocytosis

A form of endocytosis where the cell ingests extracellular fluid and its contents.

Rab protein

A type of small GTPase involved in the regulation of vesicular transport.

Ran protein

A GTPase that is involved in the transport of proteins into and out of the nucleus.

Secretory pathway

The route taken by proteins that are to be exported from the cell.

SNARE

Proteins that mediate the fusion of vesicles with their target membranes.

Tethering protein

Proteins that help to capture and hold vesicles at the target membrane prior to fusion.

Vesicle

A membrane-bound sac that transports materials within the cell.

Vesicular transport

The process of moving substances in vesicles through the cell.

Ribosomes

Molecular machines that synthesize proteins based on the genetic code.

Protein sorting

The process by which proteins are directed to their proper locations within or outside of the cell.

Signal sequences

Short peptide sequences that direct the transport of proteins to specific locations.

Secretory vesicles

Vesicles that store proteins and release them via exocytosis.

Chaperone proteins

Proteins that assist in the proper folding of other proteins.

Phagosome

A vesicle formed around a particle absorbed by phagocytosis.

Ubiquitin

A small protein that tags other proteins for degradation.

Endocytic pathways

Routes taken by substances entering the cell through endocytosis.

Lysosomal enzymes

Proteins that degrade macromolecules inside lysosomes.

Insoluble proteins

Proteins that do not dissolve well in water, often needing special handling during transport.

Hydrophobic signal sequences

Regions of proteins that facilitate their insertion into membranes.

Vesicle docking

The process of a vesicle attaching to the target membrane.

Neurotoxin

A toxin that disrupts the function of neurons.

Botulism toxin

A neurotoxin produced by Clostridium botulinum causing muscle paralysis.

Insulin secretion

Release of insulin by pancreatic cells in response to increased glucose levels.

Cystic fibrosis

A genetic disorder caused by misfolded proteins affecting ionic balance and leading to thick mucus production.

Intracellular digestion

The breakdown of material within a cell, often occurring in lysosomes.

Endosomes

Membrane-bound compartments within cells involved in sorting endocytosed material.

Transport vesicles

Vesicles that carry materials between organelles.

Cystic fibrosis transmembrane conductance regulator (CFTR)

A protein that functions as a channel for chloride ions across epithelial cell membranes.

Endocytosis pathway

Routes taken by substances entering the cell, involving vesicular transport.

Fluid-phase pinocytosis

A type of pinocytosis where fluids are non-specifically ingested.

Receptor-mediated endocytosis

The uptake of substances via specific receptors on the cell surface.

Lipids

Fatty substances essential for building cell membranes and storing energy.

Endoplasmic reticulum signal sequence

A sequence that directs proteins for synthesis on the ER.

Exocytosis pathway

The route proteins take to exit the cell.

Autophagic processes

Cellular mechanisms that recycle components through lysosomal degradation.

Endosomal sorting

The process of determining the fate of endocytosed materials.

Signal peptide

Leading peptide sequences that target proteins for specific pathways.

Nuclear localization signal

A sequence that directs a protein to the nucleus.

Hydrophilic amino acids

Amino acids that interact well with water, often found on protein surfaces.

Mitochondrial protein import

The process of proteins entering mitochondria, often requiring unfolding.

Membrane-bound ribosomes

Ribosomes attached to the endoplasmic reticulum, synthesizing proteins for secretion.

RNA-binding proteins

Proteins that interact with RNA molecules during transcription and translation.

Enzymatic digestion

Chemical breakdown of compounds by enzymes, important for cellular maintenance.

Entropy-driven processes

Processes like vesicle fusion that release free energy to drive molecular interactions.

Endocytic vesicles

Vesicles formed during endocytosis for internal cellular transport.

Immunological responses

Reactions of the immune system to pathogens, often involving phagocytosis.

Apoptotic signals

Molecular cues indicating a cell should undergo programmed cell death.

Polarized transport

Directed movement of substances in specific orientations within cells.

Non-specific uptake

Process in which various substances are taken up by a cell without targeted mechanisms.

Inter-organelle transport

Transport mechanisms between different cellular organelles.