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S Bromley

Publications and source records attributed to S Bromley.

8 recordsLinked to original sources
PubMed1998

A novel adaptor protein orchestrates receptor patterning and cytoskeletal polarity in T-cell contacts.

Recognition of antigen by T cells requires the formation of a specialized junction between the T cell and the antigen-presenting cell. This junction is generated by the recruitment and the exclusion of specific proteins from the contact area. The mechanisms that regulate these events are unknown. Here we demonstrate that ligand engagement of the adhesion molecule, CD2, initiates a process of protein segregation, CD2 clustering, and cytoskeletal polarization. Although protein segregation was not dependent on the cytoplasmic domain of CD2, CD2 clustering and cytoskeletal polarization required an interaction of the CD2 cytoplasmic domain with a novel SH3-containing protein. This novel protein, called CD2AP, is likely to facilitate receptor patterning in the contact area by linking specific adhesion receptors to the cytoskeleton.

Adaptor Proteins, Signal Transducing↗
PubMed1991

Subcortical projections to the centromedian and parafascicular thalamic nuclei in the cat.

The primary objective of this study is to identify the totality of input to the centromedian and parafascicular (CM-Pf) thalamic nuclear complex. The subcortical projections upon the CM-Pf complex were studied in the cat with three different retrograde tracers. The tracers used were unconjugated horseradish peroxidase (HRP), horseradish peroxidase conjugated to wheat germ agglutinin (WGA-HRP), and rhodamine-labeled fluorescent latex microspheres (RFM). Numerous subcortical structures or substructures contained labeled neurons with all three tracing techniques. These labeled structures included the central nucleus of the amygdala; the entopeduncular nucleus; the globus pallidus; the reticular and ventral lateral geniculate nuclei of the thalamus; parts of the hypothalamus including the dorsal, lateral, and posterior hypothalamic areas and the ventromedial and parvicellular nuclei; the zona incerta and fields of Forel; parts of the substantia nigra including the pars reticularis and pars lateralis, and the retrorubral area; the pretectum; the intermediate and deep layers of the superior colliculus; the periaqueductal gray; the dorsal nucleus of the raphe; portions of the reticular formation, including the mesencephalic, pontis oralis, pontis caudalis, gigantocellularis, ventralis, and lateralis reticular nuclei; the nucleus cuneiformis; the marginal nucleus of the brachium conjunctivum; the locus coeruleus; portions of the trigeminal complex, including the principal sensory and spinal nuclei; portions of the vestibular complex, including the lateral division of the superior nucleus and the medial nucleus; deep cerebellar nuclei, including the medial and lateral cerebellar nuclei; and lamina VII of the cervical spinal cord. Moreover, the WGA-HRP and rhodamine methods (known to be more sensitive than the HRP method) revealed several afferent sources not shown by HRP: the anterior hypothalamic area, ventral tegmental area, lateral division of the superior vestibular nucleus, nucleus interpositus, and the nucleus praepositus hypoglossi. Also, the rhodamine method revealed labeled neurons in laminae V and VI of the cervical spinal cord.

Afferent Pathways↗
PubMed1991

A multi-test alcoholic taxonomy: canonical coefficient clusters.

Little convergence has been found in the area of subtyping alcoholic personalities. Prior work has suffered from the use of single inventories, inventories with large distress factors, or inventories that lack broad theoretical appeal. The present work (N = 89) transcends idiosyncratic cluster solutions through the use of canonical correlation of the Basic Personality Inventory and the Millon Clinical Multiaxial Inventory. The resulting global canonical variates are cluster analyzed to a six-cluster solution. These subtypes are described through their scores on the canonical variates and the underlying psychometric inventories.

Adult↗
PubMed1989

Thalamocortical connections of the rostral intralaminar nuclei: an autoradiographic analysis in the cat.

In this study the pattern of projections from the rostral intralaminar thalamic nuclei to the cerebral cortex was examined in the cat by autoradiography. Injections of tritiated proline and leucine were placed into the central lateral, paracentral, central medial, and para-stria medullaris nuclei. After injections into the central lateral nucleus, label is present on the lateral side within the presylvian sulcus, in most of the suprasylvian gyrus, including the adjacent lateral and suprasylvian sulci, and in the posterior corner of the ectosylvian gyrus. On the medial side, label is present in the orbitofrontal (Of), precentral agranular (Prag), anterior limbic (La), retrosplenial (Rs), and postsubicular (Ps) areas, as defined by Rose and Woolsey ('48a). The cingulate gyrus also contains label throughout (part of which was defined as the "cingular area," Cg, by Rose and Woolsey, '48a). Label is also found on both banks of the splenial and cruciate sulci. In addition, label is present within the lateral gyrus, on both its lateral and medial sides. The paracentral projections are similar to the central lateral input. On the lateral side, label is found within the presylvian sulcus, suprasylvian gyrus and adjacent lateral and suprasylvian sulci, and posterior ectosylvian gyrus. Medially, label is present in the Of, Prag, La, Cg, Rs, and Ps areas, and within the cruciate and splenial sulci, and in portions of the lateral gyrus. Following injections of the central medial nucleus, label is present in the presylvian sulcus; but in contrast to the central lateral and paracentral projections, the suprasylvian gyrus is labeled only in its posterior part. The central medial nucleus also projects to the posterior lateral gyrus, both laterally and medially. Also, the central medial nucleus projects heavily to rostral cortical zones, which include the Of, Prag and La areas, cruciate sulcus, and the rostral cingulate gyrus. The para-stria medullaris nucleus projects only to the presylvian sulcus and orbitofrontal cortex laterally, but, medially, has an extensive input similar to the central lateral and paracentral projections in that label is present in the Of, Prag, La, Cg, Rs, and Ps areas, in the cruciate and splenial sulci, and in the posterior lateral gyrus. The laminar distribution of label is as follows: the central lateral, paracentral and para-stria medullaris nuclei project primarily to layers I and III, whereas the central medial nucleus projects to layers I and VI. In addition, the central lateral projection has a patchy appearance in the retrosplenial and postsubicular cortices.

Animals↗
PubMed1985

Effects of isomers of apomorphines on dopamine receptors in striatal and limbic tissue of rat brain.

The optical isomers of apomorphine (APO) and N-propylnorapomorphine (NPA) were interacted with three biochemical indices of dopamine (DA) receptors in extrapyramidal and limbic preparations of rat brain tissue. There were consistent isomeric preferences for the R(-) configuration of both DA analogs in stimulating adenylate cyclase (D-1 sites) and in competing for high affinity binding of 3H-spiroperidol (D-2 sites) and of 3H-ADTN (DA agonist binding sites) in striatal tissue, with lesser isomeric differences in the limbic tissue. The S(+) apomorphines did not inhibit stimulation of adenylate cyclase by DA. The tendency for greater activity or higher apparent affinity of R(-) apomorphines in striatum may reflect the evidently greater abundance of receptor sites in that region. There were only small regional differences in interactions of the apomorphine isomers with all three receptor sites, except for a strong preference of (-)NPA for striatal D-2 sites. These results do not parallel our recent observations indicating potent and selective antidopaminergic actions of S(+) apomorphines in the rat limbic system. They suggest caution in assuming close parallels between current biochemical and functional, especially behavioral, methods of evaluating dopamine receptors of mammalian brain.

Adenylyl Cyclases↗
PubMed1982

Periodic transcription of yeast histone genes.

Periodic transcription of yeast histone genes has been demonstrated by DNA excess filter hybridization of in vivo pulse-labeled RNA isolated from synchronous cell cultures. Using strains carrying cell division cycle (cdc) mutations, we show that both activation and termination of transcription are determined by temporally separable (cell cycle) events. Activation of histone mRNA synthesis occurs late in G1, at a point prior to initiation of DNA replication. Cessation of histone mRNA synthesis, however, is dependent upon the entry of cells into S. These results suggest a simple model for the control of histone gene transcription in which changes in chromatin that must precede the initiation of DNA replication also bring about activation of histone mRNA synthesis. Cessation of synthesis would occur once this region had been replicated and the chromatin restored to its prereplicative state.

DNA Replication↗
PubMed1982

Further evidence that the rna2 mutation of Saccharomyces cerevisiae affects mRNA processing.

The relative rate at which ribosomal protein 51 (rp51) mRNA is synthesized was measured by pulse-labeling cells in vivo with [3H]adenine. Two strains of Saccharomyces cerevisiae were compared: A364A (wild type) and ts368 (rna2), a temperature-sensitive strain in which the level of rp51 mRNA decreases and an intron-containing rp51 precursor RNA increases. When cells were shifted up to the nonpermissive temperature (36 degrees C), the rate of rp51 RNA synthesis was only marginally affected (75% of wild type) by the presence of the rna2 mutation. The precursor RNA was the predominant transcription product at 36 degrees C. This precursor could be converted into RNA equal in size to mature mRNA by further incubation at either 36 or 23 degrees C in the presence of unlabeled adenine. The relative half-life of the rp51 transcripts at 36 degrees C also decreased approximately twofold in ts368 as compared with A364A. All of these data imply that the precursor (intron-containing) RNA is processed inefficiently to mature mRNA and that the rp51 precursor RNA is continuously synthesized and degraded in the mutant strain at 36 degrees C.

Gene Expression Regulation↗