Endocytosis is a cellular process in which substances are brought into the cell. The material to be internalized is surrounded by an area of cell membrane, which then buds off inside the cell to form a vesicle containing the ingested materials. Endocytosis includes pinocytosis and phagocytosis. It is a form of active transport.
In biology, caveolae, which are a special type of lipid raft, are small invaginations of the plasma membrane in the cells of many vertebrates. They are the most abundant surface feature of many vertebrate cell types, especially endothelial cells, adipocytes and embryonic notochord cells. They were originally discovered by E. Yamada in 1955.
The plasma membranes of cells contain combinations of glycosphingolipids, cholesterol and protein receptors organised in glycolipoprotein lipid microdomains termed lipid rafts. Their existence in cellular membranes remains controversial. Indeed, Kervin and Overduin imply that lipid rafts are misconstrued protein islands, which they propose form through a proteolipid code. Nonetheless, it has been proposed that they are specialized membrane microdomains which compartmentalize cellular processes by serving as organising centers for the assembly of signaling molecules, allowing a closer interaction of protein receptors and their effectors to promote kinetically favorable interactions necessary for the signal transduction. Lipid rafts influence membrane fluidity and membrane protein trafficking, thereby regulating neurotransmission and receptor trafficking. Lipid rafts are more ordered and tightly packed than the surrounding bilayer, but float freely within the membrane bilayer. Although more common in the cell membrane, lipid rafts have also been reported in other parts of the cell, such as the Golgi apparatus and lysosomes.
Receptor-mediated endocytosis (RME), also called clathrin-mediated endocytosis, is a process by which cells absorb metabolites, hormones, proteins – and in some cases viruses – by the inward budding of the plasma membrane (invagination). This process forms vesicles containing the absorbed substances and is strictly mediated by receptors on the surface of the cell. Only the receptor-specific substances can enter the cell through this process.
In molecular biology, caveolins are a family of integral membrane proteins that are the principal components of caveolae membranes and involved in receptor-independent endocytosis. Caveolins may act as scaffolding proteins within caveolar membranes by compartmentalizing and concentrating signaling molecules. They also induce positive (inward) membrane curvature by way of oligomerization, and hairpin insertion. Various classes of signaling molecules, including G-protein subunits, receptor and non-receptor tyrosine kinases, endothelial nitric oxide synthase (eNOS), and small GTPases, bind Cav-1 through its 'caveolin-scaffolding domain'.
Marilyn Gist Farquhar was a pathologist and cellular biologist, Professor of Cellular and Molecular Medicine and Pathology, as well as the chair of the Department of Cellular and Molecular Medicine at the University of California, San Diego School of Medicine, who previously worked at Yale University from 1973 to 1990. She has won the E. B. Wilson Medal and the FASEB Excellence in Science Award. She was married to Nobel Laureate George Emil Palade from 1970 to his death in 2008. Her research focuses on control of intracellular membrane traffic and the molecular pathogenesis of auto immune kidney diseases. She has yielded a number of discoveries in basic biomedical research including: mechanisms of kidney disease, organization of functions that attach cells to one another, and mechanisms of secretions.
Polymerase I and transcript release factor, also known as Cavin1, Cavin-1 or PTRF, is a protein which in humans is encoded by the PTRF gene.
Potocytosis is a type of receptor-mediated endocytosis in which small molecules are transported across the plasma membrane of a cell. The molecules are transported by caveolae and are deposited directly into the cytosol.
Professor Jennifer Louise "Jenny" Martin is an Australian scientist and academic. She was the Deputy Vice-Chancellor at the University of Wollongong, in New South Wales from 2019-2022. She is a former Director of the Griffith Institute for Drug Discovery at Griffith University. and a former Australian Research Council Laureate Fellow at the Institute for Molecular Bioscience, University of Queensland. Martin is an Honorary Professor at the University of Queensland and Adjunct Professor at Griffith University. Her research expertise encompasses structural biology, protein crystallography, protein interactions and their applications in drug design and discovery.
Jennifer Lea Stow is deputy director (research), NHMRC Principal Research Fellow and head of the Protein Trafficking and Inflammation laboratory at the Institute for Molecular Bioscience (IMB), The University of Queensland, Australia. She received a PhD from Monash University in Melbourne in 1982., postdoctoral training at Yale University School of Medicine (US) in the Department of Cell Biologyand first faculty position as an assistant professor at Harvard University in the Renal Unit, Departments of Medicine and Pathology at the Massachusetts General Hospital in Boston.
Nektarios N. Tavernarakis is a Greek bioscientist, who studies Ageing, Cell death, and Neurodegeneration. He is currently Distinguished Professor of Molecular Systems Biology at the Medical School of the University of Crete, and the Chairman of the Board of Directors at the Foundation for Research and Technology, in Heraklion, Crete, Greece. He is also the founder and first Director of the Graduate Program in Bioinformatics of the University of Crete Medical School, and has served as Director of the Institute of Molecular Biology and Biotechnology, where he is heading the Neurogenetics and Ageing laboratory. He was elected Vice President of the European Research Council (ERC) in 2020, and Chairman of the European Institute of Innovation and Technology (EIT) Governing Board and Executive Committee in 2022.
Melissa Helen Little is an Australian scientist and academic, currently Theme Director of Cell Biology, heading up the Kidney Regeneration laboratory at the Murdoch Children's Research Institute. She is also a Professor in the Faculty of Medicine, Dentistry and Health Sciences, University of Melbourne, and Program Leader of Stem Cells Australia. In January 2022, she became CEO of the Novo Nordisk Foundation Center for Stem Cell Medicine reNEW, an international stem cell research center based at University of Copenhagen, and a collaboration between the University of Copenhagen, Denmark, Murdoch Children’s Research Institute, Australia, and Leiden University Medical Center, The Netherlands.
Peter Anthony Koopman is an Australian biologist best known for his role in the discovery and study of the mammalian Y-chromosomal sex-determining gene, Sry.
Alan Frederick Cowman AC, FRS, FAA, CorrFRSE, FAAHMS, FASP, FASM is an internationally acclaimed malaria researcher whose work specialises in researching the malaria-causing parasite, Plasmodium falciparum, and the molecular mechanisms it uses to evade host responses and antimalarial drugs. He is currently deputy directory of the Walter and Eliza Hall Institute of Medical Research (WEHI) in Melbourne, and his laboratory continues to work on understanding how Plasmodium falciparum, infects humans and causes disease. He was elected as a fellow of the Royal Society in 2011 and awarded the Companion of the Order of Australia in 2019 for his "eminent service to the biological sciences, notably to molecular parasitology, to medical research and scientific education, and as a mentor."
Misty Rayna Jenkins is an Australian scientist known for her research into lymphocytes and cancer treatment.
Françoise Gisou van der Goot is a Swiss-Dutch cell biologist. She is a professor and the Vice President for Responsible Transformation at EPFL.
Ludger Johannes is a French-German biochemist who has specialized in the field of endocytosis and intracellular trafficking. He and his team study how sugars attached to proteins or lipids influence the transport of biological material into eukaryotic cells.
Robert Michael Graham AO, FAA, FAHMS is an Australian-born clinician-scientist. He is the Des Renford Professor of Medicine at University of New South Wales and the Head of the Molecular Cardiology and Biophysics Division at Victor Chang Cardiac Research Institute.
Juri Rappsilber is a German chemist in the area of mass spectrometry and proteomics.
Clathrin-independent endocytosis refers to the cellular process by which cells internalize extracellular molecules and particles through mechanisms that do not rely on the protein clathrin, playing a crucial role in diverse physiological processes such as nutrient uptake, membrane turnover, and cellular signaling.
