Endomembrane System, Sorting and Vesicular Transport

These flashcards cover key terminology and concepts related to the endomembrane system, sorting, and vesicular transport as discussed in the lecture.

Endomembrane System

A system composed of membrane-bound organelles, including the endoplasmic reticulum, Golgi apparatus, lysosomes, and vesicles, that work together to transport materials within a cell.

Nuclear Transport

The process by which molecules are transported into and out of the nucleus through nuclear pore complexes.

Ran-GTPase

A GTPase involved in nuclear transport that exists in active (GTP-bound) and inactive (GDP-bound) forms.

Signal Sequence

A short peptide sequence that directs the transport of a protein to its proper location within the cell.

Translocation

The process by which a protein is moved across a membrane into an organelle after synthesis.

Co-translational Import

A mechanism by which proteins are imported into the endoplasmic reticulum during their synthesis by ribosomes.

Vesicular Transport

The movement of proteins and lipids in membrane-bound vesicles between organelles.

Anterograde Transport

The transport of materials from the endoplasmic reticulum to the cis-Golgi and onwards.

Retrograde Transport

The transport of materials from the Golgi back to the endoplasmic reticulum.

Clathrin

A protein that forms a coat around vesicles that transport materials from the plasma membrane to lysosomes.

COPI

A coat protein involved in retrograde transport from the Golgi to the endoplasmic reticulum.

COPII

A coat protein involved in anterograde transport from the endoplasmic reticulum to the Golgi.

Lysosomes

Membrane-bound organelles that contain enzymes used for intracellular digestion.

Endocytosis

The process by which cells take in external substances by engulfing them in a vesicle.

Exocytosis

The process by which cells expel materials in vesicles that fuse with the plasma membrane.

Glycosylation

A biochemical process that involves the addition of carbohydrate groups to proteins, essential for proper functioning and targeting.

Rab GTPases

Proteins that ensure the specificity of vesicle targeting by interacting with tethering proteins on target membranes.

TOM and TIM

Translocators of the outer membrane (TOM) and inner membrane (TIM) involved in protein import into mitochondria.

Mitochondrial Matrix

The space within the inner membrane of mitochondria where proteins are imported and processed.