Rockefeller University

About: Rockefeller University is a education organization based out in New York, New York, United States. It is known for research contribution in the topics: Population & Gene. The organization has 15867 authors who have published 32938 publications receiving 2940261 citations. The organization is also known as: Rockefeller University & Rockefeller Institute.

Human population: the next half century.

Abstract: By 2050, the human population will probably be larger by 2 to 4 billion people, more slowly growing (declining in the more developed regions), more urban, especially in less developed regions, and older than in the 20th century. Two major demographic uncertainties in the next 50 years concern international migration and the structure of families. Economies, nonhuman environments, and cultures (including values, religions, and politics) strongly influence demographic changes. Hence, human choices, individual and collective, will have demographic effects, intentional or otherwise.

Intracellular transport of secretory proteins in the pancreatic exocrine cell. I. Role of the peripheral elements of the Golgi complex.

Abstract: It has been established by electron microscopic radioautography of guinea pig pancreatic exocrine cells (Caro and Palade, 1964) that secretory proteins are transported from the elements of the rough-surfaced endoplasmic reticulum (ER) to condensing vacuoles of the Golgi complex possibly via small vesicles located in the periphery of the complex. To define more clearly the role of these vesicles in the intracellular transport of secretory proteins, we have investigated the secretory cycle of the guinea pig pancreas by cell fractionation procedures applied to pancreatic slices incubated in vitro. Such slices remain viable for 3 hr and incur minimal structural damage in this time. Their secretory proteins can be labeled with radioactive amino acids in short, well defined pulses which, followed by cell fractionation, makes possible a kinetic analysis of transport. To determine the kinetics of transport, we pulse-labeled sets of slices for 3 min with leucine-(14)C and incubated them for further +7, +17, and +57 min in chase medium. At each time, smooth microsomes ( = peripheral elements of the Golgi complex) and rough microsomes ( = elements of the rough ER) were isolated from the slices by density gradient centrifugation of the total microsomal fraction. Labeled proteins appeared initially (end of pulse) in the rough microsomes and were subsequently transferred during incubation in chase medium to the smooth microsomes, reaching a maximal concentration in this fraction after +7 min chase incubation. Later, labeled proteins left the smooth microsomes to appear in the zymogen granule fraction. These data provide direct evidence that secretory proteins are transported from the cisternae of the rough ER to condensing vacuoles via the small vesicles of the Golgi complex.

Endogenous MHC Class II Processing of a Viral Nuclear Antigen After Autophagy

Abstract: CD4+ T cells classically recognize antigens that are endocytosed and processed in lysosomes for presentation on major histocompatibility complex (MHC) class II molecules. Here, endogenous Epstein-Barr virus nuclear antigen 1 (EBNA1) was found to gain access to this pathway by autophagy. On inhibition of lysosomal acidification, EBNA1, the dominant CD4+ T cell antigen of latent Epstein-Barr virus infection, slowly accumulated in cytosolic autophagosomes. In addition, inhibition of autophagy decreased recognition by EBNA1-specific CD4+ T cell clones. Thus, lysosomal processing after autophagy may contribute to MHC class II-restricted surveillance of long-lived endogenous antigens including nuclear proteins relevant to disease.

Receptive field dynamics in adult primary visual cortex

Abstract: THE adult brain has a remarkable ability to adjust to changes in sensory input. Removal of afferent input to the somatosensory, auditory, motor or visual cortex results in a marked change of cortical topography1–10. Changes in sensory activity can, over a period of months, alter receptive field size and cortical topography11. Here we remove visual input by focal binocular retinal lesions and record from the same cortical sites before and within minutes after making the lesion and find immediate striking increases in receptive field size for cortical cells with receptive fields near the edge of the retinal scotoma. After a few months even the cortical areas that were initially silenced by the lesion recover visual activity, representing retinotopic loci surrounding the lesion. At the level of the lateral geniculate nucleus, which provides the visual input to the striate cortex, a large silent region remains. Furthermore, anatomical studies show that the spread of geniculocortical afferents is insufficient to account for the cortical recovery. The results indicate that the topographic reorganization within the cortex was largely due to synaptic changes intrinsic to the cortex, perhaps through the plexus of long-range horizontal connections.