Question

What is the role of APP in kinesin-1-mediated transport of protein-loaded vesicles along microtubules? How was this discovered?

Explain how oxidation during catabolism leads to production of the cell’s ATP. In other words, what happens when pyruvate is transported to mitochondria from the cytosol resulting in the production of ATP.

Answer 1

* The most abundant APP species were the fully glycosylated (~ 120-125 KD) forms of APP -695 that mature through the Golgi apparatus and are then transported anterogradelyy in axons. presumably as part of membranous vesicles that are translocated, via kinesin -mediated motors,along microtubules.

* In general, the main energy source for cellular metabolism is glucose, which is catabolized in the three subsequent processes- glycolysis,tricarboxylic acid cycle( TCA or Krebs cycle)), and finally oxidative phosphorylation- to produce ATP. In first process, when glucose is converted into pyruvate, the amount of ATP produced is low.subsequently, pyruvate is converted to acetyl coenzyme A (acetyl- CoA) which enters the TCA cycle,enabling the production of NADH. Finally, NADH is used by the respiratory chain complexes to generate a proton gradient across the inner mitochondrial membrane, necessary for the production of large amounts of ATP by mitochondrial ATP synthase. In addition,it should be mentioned that acetyl-CoA can be generated also by lipid and protein catabolism.