Dynamic balance between vesicle transport and microtubule growth enables neurite outgrowth
Fig 8
Loss of function of Level-2 SCPs requires multiple adaptations to allow NOG under physiological conditions.
We predicted a parameter set that allows steady neurite outgrowth with a velocity of 10 μm/h. To investigate Level-2 SCP dependencies we reduced the activity of the SCP Vesicle budding at the TGN by reducing the amount of Recruitment Factor 1 without compensatory increase of the budding rate. In consequence, the activities of multiple Level-2 SCPs needed to be coordinatively adapted to secure neurite outgrowth under physiological conditions (as defined by our model constraints). One possible adaptation involves the reduction in the activity of the SCPs Membrane Lipid Production, of Anterograde Microtubule-Based Vesicle Transport (via reduced kinesin receptors), of Vesicle Exocytosis (via reduced v-SNARE V) and of Membrane Protein Production of the involved transmembrane molecules. Since this option includes a constant cycling rate (i.e. rate of back transported membrane), it causes a reduction in neurite outgrowth velocity.