Foreword

Since the 19th century, when Metchnikoff fed fragments of blue litmus paper to phagocytes and observed that they turned red, indicating the presence of an “acid compartment”, biologists and physicians have been intrigued with the mechanisms of membrane internalization and trafficking and their implications for understanding physiology. In the 20th century, when much was already known at the morphological level about cell secretion and endocytosis, a major advance, the discovery of the Ypt/Rab family of GTPases, heralded the entry of an era that has propelled research in membrane trafficking into the 21st century. The discovery of Ypt1 in yeast and the subsequent discovery of the Rab GTPases in mammalian cells has revealed a vast network of interacting transport/trafficking pathways in cells not unlike, metaphorically speaking, a national highway system for packaging and distributing cargo and products from one location to another.

The course of evolution has been characterized by several large expansions in the signaling repertoire of cells and tissues accompanied by the five-fold expansion in the Rab GTPase catalog from yeast to man. This expansion, along with the corresponding need for additional Rab-specific effectors, motors, exchange factors and GAPs, has broadened our understanding of the immense impact of the Ypt/Rab family on human physiology and health.

A new offering by Li and Segev entitled “Rab GTPases and Membrane Trafficking” brings us up to date on many of the recent developments in Ypt/Rab biology and physiology. Following an excellent introduction by the Li and Segev that touches on many of the recent advances in this rapidly developing field, a collection of a dozen chapters focus on selected Ypt/Rabs and the transport and signaling functions that they oversee. A superb collection of contributors brings both diversity and substance to the volume while highlighting the novelty of individual Ypt/Rab GTPases. The last selection on the evolution of the Ypt/Rab family provides an excellent finale. The eBook makes good use of cartoons, is amply referenced and should be of great value to graduate students and aficionados alike.