Protein and Lipid Requirements for Endocytosis

Abstract

Genetic and biochemical studies in yeast and animal cells have led to the identification of many components required for endocytosis. In this review, we summarize our understanding of the endocytic machinery with an emphasis on the proteins regulating the internalization step of endocytosis and endosome fusion. Even though the overall endocytic machinery appears to be conserved between yeast and animals, clear differences exist. We also discuss the roles of phosphoinositides, sterols, and sphingolipid precursors in endocytosis, because in addition to proteins, these lipids have emerged as important determinants in the spatial and most likely temporal specificity of endocytic membrane trafficking events.

A role for yeast oxysterol-binding protein homologs in endocytosis and in the maintenance of intracellular sterol-lipid distribution

“…Actin is essential for yeast endocytosis (Kubler and Riezman, 1993;Munn et al, 1995), and many genes required for endocytosis affect actin assembly and dynamics (reviewed by D'Hondt et al, 2000). To examine whether OSH-associated endocytosis defects were actin dependent, we examined the actin cytoskeleton in OSH mutants.…”

CART: An Hrs/Actinin-4/BERP/Myosin V Protein Complex Required for Efficient Receptor Recycling

“…Endocytosis is required for the uptake of essential nutrients from the extracellular environment as well as for retrieval of proteins and lipids that are added to the plasma membrane during fusion of regulated and constitutive secretory vesicles (De Camilli and Takei, 1996;Koenig and Ikeda, 1996;Robinson et al, 1996;Mukherjee et al, 1997;Schmid, 1997;Betz and Angleson, 1998;Koenig et al, 1998;Stoorvogel, 1998;D'Hondt et al, 2000;Gruenberg, 2001). The endocytic pathway can be separated into numerous stages based on the movement of cargo and the identification of morphologically defined compartments (De Camilli and Takei, 1996;Koenig and Ikeda, 1996;Robinson et al, 1996;Mukherjee et al, 1997;Schmid, 1997;Betz and Angleson, 1998;Koenig et al, 1998;Stoorvogel, 1998;D'Hondt et al, 2000;Gruenberg, 2001).…”

“…The endocytic pathway can be separated into numerous stages based on the movement of cargo and the identification of morphologically defined compartments (De Camilli and Takei, 1996;Koenig and Ikeda, 1996;Robinson et al, 1996;Mukherjee et al, 1997;Schmid, 1997;Betz and Angleson, 1998;Koenig et al, 1998;Stoorvogel, 1998;D'Hondt et al, 2000;Gruenberg, 2001). Early events in the endocytic process include membrane invagination and vesicle budding from the plasma membrane, formation of transport vesicles, and fusion with early endosomes.…”

“…Early events in the endocytic process include membrane invagination and vesicle budding from the plasma membrane, formation of transport vesicles, and fusion with early endosomes. Later events include cargo sorting, and additional transport/fusion steps, including those responsible for transport to the lysosome for degradation, and those responsible for recycling back to various compartments (De Camilli and Takei, 1996;Koenig and Ikeda, 1996;Robinson et al, 1996;Mukherjee et al, 1997;Schmid, 1997;Betz and Angleson, 1998;Koenig et al, 1998;Stoorvogel, 1998;D'Hondt et al, 2000;Gruenberg, 2001). Although much progress has been made in elucidating the molecular processes involved in early endocytic events, such as those involved in the genesis of clathrin-coated endocytic transport vesicles, an equally clear understanding of later events remains elusive.…”

Sphingolipids and membrane biology as determined from genetic models

“…Endocytosis is a key process for the cellular uptake of extracellular nutrients. It also regulates membrane dynamics and cellular responses to external stimuli by modulating cell surface-receptor activity [42]. Endocytosed vesicles are dynamic.…”