Paul Cullen’s Lectures for BIO402/502 Office hours: Friday 2PM or by appointment Test will be on October 29th 7PM-9PM Short answer, medium answer, and essay. Primarily from the lectures, with the book as a backup.
Exocytosis: Delivery of Secretiory Vesicles to the Cell Suface Retrograde Transport: Delivery of Vesicles to Internal Compartments
HIV enters through membrane fusion Influenza enters through receptor-mediated endocytosis Snare-like IM-like Proteins Hydrophobic Tails exposed
Phagocytosis Specialized form of receptor-mediated endocytosis Macrophages (white blood cells) Food (in microorganisms), dead cells (10 11 red blood cells/day), glass, Latex beads, asbestos fibers, and antigens, but not other live cells
Temporal Order of Clathrin-Mediated Endocytic Intermediates PI(4,5)P 2 PIPK- Recruitment of Clathrin Assembly Factors AP-2* AP180A,B* Eps15 Clathrin Hip1R* Epsin* Membrane Curvature Amphiphysin2* Endophilin Membrane Restriction/Fission Vesicle Release Dynamin* Actin polymerization PI(4,5)P 2 -binding Proteins* PI(4,5)P 2 Conner and Schmid, Nature 2003
Transcytosis from the Basolateral membrane To the Apical Membrane Allows passage of materials Across cellular boundaries
Antibodies must also transverse the intestine of the infant acidic neutral
Figure 12-6 Molecular Biology of the Cell (© Garland Science 2008)
Figure 12-21a Molecular Biology of the Cell (© Garland Science 2008) Some Proteins made in the mito.
Figure Molecular Biology of the Cell (© Garland Science 2008) The Mitochondrial Import Sequence is an amphipathic alpha helix
Figure Molecular Biology of the Cell (© Garland Science 2008) TOM = cytosolic proteins to the intermembrane space TIM = cytosolic proteins to the matrix and inner membrane OXA = mitochondrially produced proteins to the intermembrane space
Figure Molecular Biology of the Cell (© Garland Science 2008) An in vitro experiment to determine how mitochondrial transport occurs
Figure Molecular Biology of the Cell (© Garland Science 2008) Cytosolic chaperones like Hsp70 keep proteins Unfolded until they are fed into the mitochondria And they contribute to the import process.
The RTG Network: a signaling pathway from the mitochondria to the Nucleus. Mitochondrial retrograde signaling is a pathway of communication from mitochondria to the nucleus under normal and pathophysiological conditions. The best understood of such pathways is retrograde signaling in the budding yeast Saccharomyces cerevisiae. It involves multiple factors that sense and transmit mitochondrial signals to effect changes in nuclear gene expression; these changes lead to a reconfiguration of metabolism to accommodate cells to defects in mitochondria. Analysis of regulatory factors has provided us with a mechanistic view of regulation of retrograde signaling. Here we review advances in the yeast retrograde signaling pathway and highlight its regulatory factors and regulatory mechanisms, its physiological functions, and its connection to nutrient sensing, TOR signaling, and aging.
Aging, the greatest disease of all! Like many young scientists with a novel idea, Kenyon encountered more skepticism than support in the early 1990s. Indeed, one fellow scientist, worried that she had gone “over the edge,” warned that if she continued to insist that aging was subject to genetic regulation, she would soon fall off the Earth altogether. But her world turned out to be round, not flat. And now firmly anchored as, if not exactly the “queen of aging research,” then certainly its ace, Kenyon commands no fewer than 386,000 entries on a standard Google search. The story is now well-known. One of Kenyon’s lab rotation students — Ramon Tabtiang — in one of his very first experiments, picked a needle out of the haystack that is the C. elegans genome. In short, he found a mutant gene, dubbed daf-2, that made worms live twice as long.