Actin is as essential to a cell’s function as Girl Scout cookies are to mine. With all of the biologists sorting out the many different functions and regulators of actin, it’s easy to get a little overwhelmed as a reader and actin admirer. Thankfully, a recent paper delves into the world of RhoA to clarify exactly what it is doing in our skin cells.
RhoA is an actin small GTPase, which means it serves as a molecular switch to regulate actin cytoskeleton organization. RhoA is important in many processes including cytokinesis, cell-cell junctions, and stress fiber formation. Previous research led to the thought that RhoA was crucial for skin development and function, but a recent paper finds otherwise. In this paper, Jackson and colleagues generated mice with RhoA absent from keratinocytes, which are the outer-most cells of our skin. The skin of these mice developed similar to control mice, yet the loss of RhoA in keratinocytes did lead to problems in cytokinesis and cell migration and spreading. Images above show normal (left) and RhoA mutant (right) epidermis tissue with labels for different keratinocyte proteins (red), the cell adhesion receptor α6 integrin (green), and DNA (blue). Both normal and RhoA mutants show normal skin development.
Jackson, B., Peyrollier, K., Pedersen, E., Basse, A., Karlsson, R., Wang, Z., Lefever, T., Ochsenbein, A., Schmidt, G., Aktories, K., Stanley, A., Quondamatteo, F., Ladwein, M., Rottner, K., van Hengel, J., & Brakebusch, C. (2011). RhoA is dispensable for skin development, but crucial for contraction and directed migration of keratinocytes Molecular Biology of the Cell, 22 (5), 593-605 DOI: 10.1091/mbc.E09-10-0859