Question

You are examining fibroblast cells in the laboratory, and decide to alter their conditions and test the affect on cell migration. What effect would you expect if:  

a) You coated the slide with a single stripe of fibronectin?

b) Treated them with a Rho kinase inhibitor?

c) Treated them with a drug that activated WASP and Arp 2/3?  

Answer 1

1. Answer:

When fibroblast cells are coated with fibronectin stripes, the cell elongates itself along the major axis of the pattern. The nucleus of the cell elongated due to the compressive pressure applied by cytoskeletal microtubule motors which was applied by actin stress fibers. Hence, the extent of nucleus elongation can exhibit multimodal behaviour among some cell lines such as human mesenchymal stem cells (HMSCS), so that the histogram of aspect ratio of the HMSCS shows two distinct groups of elongated and round nucleus. Because of the pivotal role that nuclear deformation plays in the behaviour and fate of cells, substantial interest has developed exploring this opportunity to control the deformation using substrate topography particularly for control of proliferation and differentiation of stem cells.

2. Answer:

when treated with Rho-associated protein kinase (ROCK) inhibitors reduces migration and poliferation of fibroblast cells. for example, Prevention of transforming growth factor β (tgfβ)-induced transdifferentiation of cultured scleral fibroblasts to myofibroblasts by Rho-associated protein kinase (ROCK) inhibitors. Additionally, they tested whether local delivery of ROCK inhibitors reduced scleral fibroblast proliferation in response to chronic intraocular pressure (IOP) elevation. These reduce tgfβ-induced myofibroblast transdifferentiation and glaucoma-induced scleral cell proliferation.

3. Answer:

The Arp2/3 complex – an actin filament nucleating and organizing factor – appears to be a central player in the cellular control of actin assembly. Recently, a molecular pathway leading from key signalling molecules to actin filament nucleation by the Arp2/3 complex has been discovered. In this pathway, the GTPase CDC42 acts in concert with WASP family proteins to activate the Arp2/3 complex. The coordination of cell shape change and locomotion requires that actin polymerization at the cell cortex be tightly controlled in response to both intracellular and extracellular.

Note: The provided answer is as per my knowledge may be or may not be 100% correct, but definitely relevant to your question thank you so much.