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February 01, 2010
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Date:03TuesdayMay 2011Lecture
p53, a novel regulator of lipid metabolism pathways
More information Time 12:15 - 12:15Location Wolfson Building for Biological ResearchLecturer Ido Goldstein Organizer Department of Molecular Cell BiologyContact Abstract Show full text abstract about Maintaining normal lipid homeostasis is crucial for every bi...» Maintaining normal lipid homeostasis is crucial for every biological system. Although the transport of lipids in circulation in the form of lipoprotein complexes is an elaborate process orchestrated mainly by the liver, the molecular underpinnings of hepatic lipoprotein regulation are not entirely resolved. In this study, we identify a
novel role for the p53 protein in regulating lipid and lipoprotein metabolism, a process not conceptually conceived as related to p53, which is known mainly in its tumor suppressive functions. Gene expression microarray analysis revealed a group of 341 genes whose expression was induced by p53 in the liver-derived cell line HepG2.
Twenty of these genes encode proteins involved in many aspects of lipid homeostasis, especially lipoprotein metabolism. The mode of regulation of three representative genes (pltp, abca12 and cel) was further characterized. In addition to HepG2, the genes were induced in a p53-dependent manner in other cell types namely Hep3B cells, mouse hepatocytes, human liver cells and fibroblasts. Furthermore, p53 was found to bind to their promoter in designated p53 responsive elements (as measured by chromatin immunoprecipitation) and was able to increase the transcription of a reporter gene located downstream of the genes' promoters. Of note, p53 induced a significant elevation in the protein level of PLTP and CEL. Importantly, p53 augmented the activity of secreted PLTP, which plays a major role in lipoprotein biology and atherosclerosis pathology. These findings expose another layer of p53 functions unrelated to tumor suppression and render it a novel regulator of hepatic lipid metabolism and consequently of systemic lipid homeostasis and atherosclerosis development.
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Date:03TuesdayMay 2011Cultural Events
"Aristrocrats" - Cameri Theater
More information Time 20:30 - 20:30Location Michael Sela AuditoriumContact -
Date:04WednesdayMay 2011Lecture
Forum on Mathematical Principles in Biology
More information Time 10:00 - 11:00Title A design principle for protein promiscuityLocation Arthur and Rochelle Belfer Building for Biomedical ResearchLecturer Dima Lukatsky Organizer Department of Molecular Cell BiologyContact -
Date:04WednesdayMay 2011Lecture
Fast Spectral Algorithms for Graph Partitioning and Graph Decomposition
More information Time 11:00 - 11:00Location Ziskind Bldg.Lecturer Nisheeth Vishnoi
Microsoft Research IndiaOrganizer Faculty of Mathematics and Computer Science -
Date:04WednesdayMay 2011Lecture
Predictive Sparse Coding:A Dynamical Circuit Model of Early Sensory Processing
More information Time 12:30 - 12:30Location Gerhard M.J. Schmidt Lecture HallLecturer Prof. Dmitri Chklovskii
Janelia Farm, HHMI, USAOrganizer Department of Brain SciencesContact Abstract Show full text abstract about In early sensory systems, such as retina and olfactory bulb ...» In early sensory systems, such as retina and olfactory bulb in vertebrates or optic and antennal lobes in invertebrates, information about the world converges from a large number of receptors onto a much smaller number of projection neurons. Such bottleneck in the communication channel to the higher brain areas (Attneave, 1954, Barlow & Levick, 1976) can be overcome for sensory stimuli containing correlations by the predictive coding strategy (Srinivasan et al, 1982). In case of the retina, instantaneous subtraction of the least squares prediction compresses information and results in center-surround biphasic receptive fields. However, explaining variation of receptive fields with SNR (Srinivasan et al, 1982, Van Hateren, 1992, Atick & Redlich, 1990) would require circuit re-wiring which is unlikely on short time scales. Here we develop the predictive coding idea by proposing that a non-linear recurrent neuronal circuit can implement predictive coding adaptively: stimuli of different SNR result in different inhibitory surrounds. We solve the transient dynamics of this circuit in response to a step-like stimulus and demonstrate that it communicates a residual of the regularization path to higher brain areas. Thus, we are able to map a non-trivial computation on a concrete neuronal circuit and provide a theoretical framework to understand neural coding for many physiological experiments. -
Date:04WednesdayMay 2011Cultural Events
"Aristrocrats" - Camari Theater
More information Time 20:30 - 20:30Location Michael Sela AuditoriumContact -
Date:05ThursdayMay 2011Lecture
Uniqueness and non-uniqueness for stochastic heat equations with H"older continuous coefficients
More information Time 11:00 - 11:00Location Ziskind Bldg.Lecturer Leonid Mytnik
TechnionOrganizer Faculty of Mathematics and Computer Science -
Date:05ThursdayMay 2011Lecture
TBA
More information Time 11:15 - 12:30Location Edna and K.B. Weissman Building of Physical SciencesLecturer Prof. Elad Schneidman
Department of NeurobiologyOrganizer Faculty of PhysicsContact -
Date:05ThursdayMay 2011Colloquia
Optimal population coding by noisy spiking neurons
More information Time 11:15 - 12:30Location Edna and K.B. Weissman Building of Physical SciencesLecturer Prof. Elad Schneidman
WeizmannOrganizer Faculty of PhysicsContact Abstract Show full text abstract about The In different neural systems, the collective activity of...» The In different neural systems, the collective activity of populations of neurons responding to natural-istic stimuli is well described by second order “maximum entropy” or Ising models. We asked, how should such interactions in the network be organized to maximize the amount of information represent-ed in population responses about the stimulus it was presented with? To this end, we extended the line-ar-nonlinear Poisson model of single neurons to include pairwise interactions, yielding a stimulus de-pendent, pairwise maximum entropy model. We found that as we varied the noise level in single neurons and the distribution of network inputs, the optimal pairwise interactions smoothly interpolated to achieve network functions that are usually regarded as discrete – stimulus decorrelation, error correc-tion, and independent encoding. These functions reflected a tradeoff between efficient consumption of finite neural bandwidth, and the use of redundancy to mitigate noise. Spontaneous activity in the optimal network reflected stimulus induced activity patterns, and single neuron response variability overes-timated network noise. Our analysis suggests that rather than having a single coding principle hardwired in their architecture, networks in the brain should adapt their function to changing noise and stimulus correlations. Initial results from the vertebrate retina indeed show how it relies on the network’s ‘ground states’ to encode information about the stimulus to the brain. -
Date:05ThursdayMay 2011Lecture
A Universal and Exact Linear Framework for Estimation Registration and Recognition of Deformable Objects
More information Time 12:00 - 12:00Location Ziskind Bldg.Lecturer Joseph M. Francos
Ben-Gurion UniversityOrganizer Faculty of Mathematics and Computer Science -
Date:05ThursdayMay 2011Lecture
Modeling the early steps of viral infection and analysis of cytoplasmic viral trajectories
More information Time 14:15 - 14:15Title Astro RoomLocation Edna and K.B. Weissman Building of Physical SciencesLecturer David Holcman
Ecole Normale Superieure, FranceOrganizer Department of Physics of Complex SystemsContact -
Date:08SundayMay 2011Lecture
"Biomineralization strategies in the acorn barnacle Balanus amphitrite"
More information Time 10:00 - 12:00Location The David Lopatie Hall of Graduate StudiesLecturer Gal Mor Khalifa
M.Sc. student of Prof. Lia Addadi & Prof. Stephen Weiner Department of Structural Bioloy, WISOrganizer Department of Chemical and Structural BiologyContact -
Date:08SundayMay 2011Lecture
Property Testing Lower Bounds via Communication Complexity
More information Time 11:00 - 11:00Location Ziskind Bldg.Lecturer Kevin Matulef
IIIS, Tsinghua UniversityOrganizer Faculty of Mathematics and Computer Science -
Date:08SundayMay 2011Lecture
The geological input of the Japan happenings and a look at our region
More information Time 11:00 - 11:00Location Sussman Family Building for Environmental SciencesLecturer Prof. Emanuel Mazor
Weizmann Institute of Science Environmental Sciences Dept.Organizer Department of Earth and Planetary SciencesContact -
Date:08SundayMay 2011Lecture
Journal club - A discussion on selected articles
More information Time 12:30 - 14:00Location Dannie N. Heineman LaboratoryLecturer Dr. Nir Sapir Organizer Nella and Leon Benoziyo Center for AstrophysicsContact -
Date:08SundayMay 2011Lecture
To be announced
More information Time 13:00 - 13:00Location Arthur and Rochelle Belfer Building for Biomedical ResearchLecturer Efrat Dvash
Menachem Rubinstein's group Dept. of Molecular Genetics, WISOrganizer Department of Molecular GeneticsContact -
Date:08SundayMay 2011Lecture
Sphingosine-1-phosphate: frpom insipid lipid to a regulator of cancer and inflammation
More information Time 14:00 - 14:00Location Max and Lillian Candiotty BuildingLecturer Prof. Sarah Spiegel
Dept. Biochemistry and Molecular Biology Virginia Commonwealth University School of Medicine Richmond, VA. USAOrganizer Department of Immunology and Regenerative BiologyContact -
Date:09MondayMay 2011Cultural Events
Ceremony marking Remembrance Day for Israel's Fallen Soldiers and Victims of Terrorism
More information Time 11:00 - 12:45Location Helen and Milton A. Kimmelman BuildingContact -
Date:11WednesdayMay 2011Lecture
Lumen formation in the Drosophila heart
More information Time 10:00 - 10:00Location Arthur and Rochelle Belfer Building for Biomedical ResearchLecturer Prof. Talila Volk
Dept. of Molecular Genetics, WISContact -
Date:11WednesdayMay 2011Colloquia
Faculty of Chemistry Colloquium- Prof. Harold Kroto
More information Time 11:00 - 12:30Title CARBON IN NANO AND OUTER SPACELocation Gerhard M.J. Schmidt Lecture HallLecturer Prof. Harold Kroto
Nobel Laureate for the discovery of the C60 Dept. of Chemistry & Biochemistry The Florida State UniversityOrganizer Faculty of ChemistryContact Abstract Show full text abstract about The age-old awe that man has had for the heavens has driven ...» The age-old awe that man has had for the heavens has driven almost all aspects of human culture and knowledge and resulted in technologies with generally positive, though occasionally negative effect. Arguably the most positive have taken place since Galileo recognized that the phases of Venus provided the evidence that confirmed the Copernican heliocentric system and cemented his position firmly as the “Father of Science”. From this moment on we had, at long last, a straightforward philosophical construct and language which enabled mankind to determine what is and is not “True”. Particularly important truths have resulted from the curiosity that humans have had for a detailed understanding of the way Universe works. This led to the development of astrophysics and the associated technologies that have been spun-off. Not least of these has been the telescope – from Galileo’s beautiful original design to the fantastic satellite-born devices put up by NASA. These have not only enabled us to observe the planets and stars more clearly but we have been able to see to the very edge of the Universe and make a plethora of discoveries about all aspects of the Universe from the occupants of the space between stars to the processes occurring deep inside stars. Perhaps the most fundamental advance based on space observations led to the development of Classical Mechanics in order to understand the motions of the planets and comets and concommitantly the development Calculus, one of the greatest of Mathematical achievements. As Quantum Mechanics developed along with Spectroscopy it was inevitable that we should start to study the atomic and molecular composition of heavenly bodies - first hot stars as well as cool comets. With the development of radiotelescopes, the very cold interstellar medium was found to be a veritable Pandora's Box, full to the brim with fascinating and exotic molecules, dust particles and also some highly puzzling material responsible for some as yet unidentified spectroscopic features. These latter are known as the Diffuse Interstellar Bands (DIBs) first observed in the 1920s.
Particularly fascinating, curious and crucial has been the role that the element carbon has played in almost every aspect of the development of our understanding of both the physical and natural sciences. The fact that the element is at all abundant is due to a curious set of coincidences involving its nucleosynthesis from helium in stars. If one furthermore adds into the overall carbon equation its uniquely profuse chemistry, ie Organic Chemistry, it is hard to conceive that life could be based on any other element. The most recent big surprise that the element had up its sleeve was the existence of C60, Buckminsterfullerene, the third well-defined form of carbon. The discovery was made serendipitously in 1985 during laboratory experiments which attempted to explain the chemical synthesis of some unusually long linear carbon chain molecules detected in the interstellar medium in the 1970’s. A second aim of these experiments involved curiosity as to whether the carriers of the DIBs might be long linear carbon chains. Interestingly the extraction of C60 in 1990 by Kraetschmer and Huffman resulted from experiments aimed at understanding another mysterious feature known as the 217nm hump and conjectured to also involve carbon – perhaps carbonaceous dust particles. The fact that this third, well-defined, form of carbon had been hiding in the shadows since time immemorial brings to mind the mysterious character lurking in the dark streets of Vienna, made famous by Orson Welles in the classic movie “The Third Man”. In fact we now know that the molecule forms fleetingly within sooting flames but is immediately destroyed as it passes through the flame barrier into an oxygen atmosphere. On the basis of such revelations the suggestion that C60 might exist in space and be responsible for the DIBs (Kroto & Jura) seemed an as good, if not a better, possibility than most other ideas that had heretofore been proposed. Especially compelling support for the idea that C60 existed in space lay in the fact that the original discovery was made serendipitously during laboratory experiments designed to simulate the atmospheric conditions in cool red giant carbon stars. This conjecture has just been confirmed by Cami et al who have found infra red bands in the spectra obtained by NASA’s Spitzer satellite telescope. The discovery also makes some recent work here at FSU on endohedral fullerenes, in which atoms are trapped inside the carbon cage, extremely relevant to certain anomalous isotope ratios observed in meteorites, in particular carbonaceous chondrites. This is yet another example of the remarkably synergistic relationship between terrestrial and space science. In these difficult times it lends useful support for the fundamental value of "Blue Skies" or perhaps more accurately “Black Skies” cross-disciplinary research. All these results taken together suggest that the 90 year-old mystery of the carrier of the DIBs might be close to being resolved at long last.
