they contain ‘gamma-tubulin ring complex’ that make up the circular features around the peri-centriole-complex, a ton of proteins around the centrosomes to hold them. They stabilize microtubule growing filaments by binding the minus end. As long as there is enough GTP bound dimers to add on.
the grip proteins bind up the minus end of a microtubule, and that allows the tubule to grow rapidly at the plus end as long as there are GTP bound dimers. The grip proteins allows the orientation to take place to drive mitosis
Nerve cells are polar w/long axons and short dendrites, so we have stabilized microtubules that have centrosomes that are responsible for the polarity. The dendrites don’t have a polarity or MTOC so the microtubules line up in opposite if not random ways.
Apical and basal ends, plus end at end, apical, and MTOCS attach to minus end and stabilize minus end of MT
Basal bodies help orient polarity of epithelial cells.
Outer doublets are held together by stabilizing proteins, such as nexin, and the inner dynein arm, which allows outer tubule doublet to slide along one another and yet be held together to create a whip-like movement, such as cilia or cilia-like structures.
Bind individual actin filaments and align them so that filopodia can function
Filopodia are fingerlike projects at the edge of the cell. Protrude out of the membrane. Provide an ability to feel out in space and find things to take up for movement or adhesion with neighboring cells.
Bundling in filopodia is important for elongation.