Cell Bio Protein Trafficking, Nuclear Transport, Mitochondrial T

What is protein trafficking?

Which organelles are part of the endomembrane system?

• Rough E.R., Golgi appartus, Lysosomes, Vesicles, Cell membrane

• Mitochondria, Chloroplast, Nucleus

• Nucleus, Cytoplasm, Rough E.R.

How do proteins get to where they need to function?

What do Importins and Exportins do?

• Pump Na+ and K+ in/out of the cell

• Recognize nuclear localization sequences (NLS) and nuclear export signals (NES)

• Embed in the Nuclear Membrane

What does the Ran protein do?

• Controls the direction of nuclear transport

• Breaks down the cell membrane

• Involved in oxidative phosphorylation

• Binds ATP for transport

How are proteins trafficked to the mitochondria?

Proteins enter the endoplasmic reticulum co-translationally and fold into their final shape in the ER lumen and can undergo posttranslational modification

• True

• False

The Rough ER is studded with ribosomes and is the site of lipid, phospholipid, and steroid synthesis

• True

• False

Answer explanation

The Rough ER is studded with ribosomes but does not serve that function. The Rough ER is the site of protein biosynthesis.

Hsp70 (heat shock protein 70) is a important chaperone protein for mitochondrial trafficking.

• True

• False

Nuclear pores are the only way proteins, ribosomal subunits, mRNAs, and tRNAs can exit the nucleus

• True

• False