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.

CRISPR-Cas immunity in prokaryotes

Abstract: Prokaryotic organisms are threatened by a large array of viruses and have developed numerous defence strategies. Among these, only clustered, regularly interspaced short palindromic repeat (CRISPR)-Cas systems provide adaptive immunity against foreign elements. Upon viral injection, a small sequence of the viral genome, known as a spacer, is integrated into the CRISPR locus to immunize the host cell. Spacers are transcribed into small RNA guides that direct the cleavage of the viral DNA by Cas nucleases. Immunization through spacer acquisition enables a unique form of evolution whereby a population not only rapidly acquires resistance to its predators but also passes this resistance mechanism vertically to its progeny.

A major surface protein on group A streptococci is a glyceraldehyde-3-phosphate-dehydrogenase with multiple binding activity.

Abstract: The surface of streptococci presents an array of different proteins, each designed to perform a specific function. In an attempt to understand the early events in group A streptococci infection, we have identified and purified a major surface protein from group A type 6 streptococci that has both an enzymatic activity and a binding capacity for a variety of proteins. Mass spectrometric analysis of the purified molecule revealed a monomer of 35.8 kD. Molecular sieve chromatography and sodium dodecyl sulfate (SDS)-gel electrophoresis suggest that the native conformation of the protein is likely to be a tetramer of 156 kD. NH2-terminal amino acid sequence analysis revealed 83% homology in the first 18 residues and about 56% in the first 39 residues with glyceraldehyde-3-phosphate dehydrogenase (GAPDH) of eukaryotic or bacterial origin. This streptococcal surface GAPDH (SDH) exhibits a dose-dependent dehydrogenase activity on glyceraldehyde-3-phosphate in the presence of beta-nicotinamide adenine dinucleotide both in its pure form and on the streptococcal surface. Its sensitivity to trypsin on whole organism and its inability to be removed with 2 M NaCl or 2% SDS support its surface location and tight attachment to the streptococcal cell. Affinity-purified antibodies to SDH detected the presence of this protein on the surface of all M serotypes of group A streptococcal tested. Purified SDH was found to bind to fibronectin, lysozyme, as well as the cytoskeletal proteins myosin and actin. The binding activity to myosin was found to be localized to the globular heavy meromyosin domain. SDH did not bind to streptococcal M protein, tropomyosin, or the coiled-coil domain of myosin. The multiple binding capacity of the SDH in conjunction with its GAPDH activity may play a role in the colonization, internalization, and the subsequent proliferation of group A streptococci.

Efferents from medial basal forebrain and hypothalamus in the rat. II. An autoradiographic study of the anterior hypothalamus.

Abstract: Using tritiated amino acid autoradiography, the efferent projections of the anterior hypothalamic area (AHA) were studied in albino rats. Axons from AHA neurons were not confined to local projections in the hypothalamus. Ascending AHA axons ran through the preoptic region, joined the diagonal band and distributed in the lateral septum. Descending AHA efferents within the hypothalamus coursed in a bundle ventromedial to the fornix. Projections were observed to the dorsomedial, ventromedial, arcuate and dorsal premammillary nuclei, and to the median eminence. Sweeping dorsomedially in the posterior hypothalamus, some AHA axons distributed in the central grey. AHA axons staying ventral projected to the supramammillary region, ventral tegmental area, raphe nuclei and midbrain reticular formation. Other AHA efferents distributed to the periventricular thalamus, to the medial amygdala via the stria terminalis or supraoptic commissure, and to the lateral habenula through the stria medullaris. For comparison with the AHA, efferent projections from the paraventricular nucleus (PVN) and from the ventromedial nucleus and adjacent basal hypothalamus (VMR) were studied. Projections from PVN neurons were not restricted to the median eminence and neurohypophysis. PVN efferents also distributed to many of the same regions as did those of the AHA but had somewhat different fiber trajectories and longer descending projections. VMR efferents were more widespread than those of the AHA, with projections extending into the lateral zona incerta and pontine reticular formation. Projections from the AHA were distinct from those of the medial preoptic area (mPOA). For example, while AHA axons descended in a bundle ventromedial to the fornix, mPOA axons ran in the medial forebrain bundle. Such anatomical differences may underlie experimentally demonstrated functional differences between the mPOA and AHA, for instance, in mediation of male and female sex behaviors.

Trypanothione: a novel bis(glutathionyl)spermidine cofactor for glutathione reductase in trypanosomatids

Abstract: Glutathione reductase from trypanosomes and leishmanias, unlike glutathione reductase from other organisms, requires an unusual low molecular weight cofactor for activity. The cofactor was purified from the insect trypanosomatid Crithidia fasciculata and identified as a novel glutathione-spermidine conjugate, N1,N8-bis(L-gamma-glutamyl-L-hemicystinyl-glycyl)spermidine, for which the trivial name trypanothione is proposed. This discovery may open a new chemotherapeutic approach to trypanosomiasis and leishmaniasis.