Ras Pathway. Ras is a membrane-associated guanine nucleotide-binding protein that is normally activated in response to the binding of extracellular signals, such as growth factors, RTKs (Receptor Tyrosine Kinases), TCR (T-Cell Receptors) and PMA (Phorbol-12 Myristate-13 Acetate).
Sicily Description. Sicily is Italy's largest island and the largest island in theMediterranean Sea. It's also a geographical and political region of Italy, famed for its beautiful beaches, cuisine, and fascinating history.
The coasts of Sicily's small islands are equally varied, ranging from spectacular promontories to inviting beaches. Whatever kind of coastline appeals to you is most probably here in Sicily. However you arrive in Sicily, the coast is the first thing you encounter. It so happens that the principal airports are not far from the shore, and neither are the major cities. This is not an accident of Sicilian history.