Many features of the actin cytoskeleton are regulated by microtubules and microtubule-binding proteins. One major function of smooth muscle cells, contraction, is accomplished by acto-myosin stress fibers. We found that stress fibers and contractile properties are strikingly altered in cells depleted of microtubule-binding proteins CLASPs.

Disorganized stress fibers (above right) cannot support oriented contraction. Indeed, CLASP-depleted cells produce altered wrinkle patterns when plated on thin silicon films (below).

Now, we would like to know:

What is the mechanism of CLASP-dependent regulation of actin organization in vascular smooth muscle cells? 

What are the molecular players involved  in this regulation?