GPI Membrane Anchors reviews major advances in our understanding of glycosylphosphatidylinositol (GPI) membrane anchors. The book examines the GPI structure and its originality as an anchoring device, its ubiquitous distribution, the main steps of its biosynthetic pathway, and the elegant means by which a protein signals for GPI attachment. It also presents evidence for the uniqueness of GPI as a tag in intracellular traffic and as a mediator of transmembrane signaling. This volume is organized into 20 chapters and begins with a discussion of the structural requirements of a nascent protein for processing to a PI-G anchored form, with emphasis on experiments on intact cells and cell-free systems. It then turns to the mechanisms underlying signal transduction by GPI-anchored membrane proteins, the LY-6 superfamily of GPI-anchored molecules, and glycosylated-phosphatidylinositols as virulence factors in Leishmania. The reader is also introduced to the molecular biology of GPI-anchored border hydrolases, the role of GPIs and their inositolglycan derivatives in the mediation of insulin and growth factor function, and biosynthesis and cellular localization of GPI-modified glycoproteins in Saccharomyces cerevisiae. An account of electrospray mass spectrometry of a C-terminal peptide purified from the scrapie isoform of the scrapie prion protein is also given. The book concludes with a chapter on GPI-anchored recognition molecules that function in axonal fasciculation, growth, and guidance in the nervous system. This book is a valuable resource for students and researchers in the fields of cell biology and biochemistry.