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Robert J. Lefkowitz

Bio: Robert J. Lefkowitz is an academic researcher from Howard Hughes Medical Institute. The author has contributed to research in topics: Receptor & G protein-coupled receptor. The author has an hindex of 214, co-authored 860 publications receiving 147995 citations. Previous affiliations of Robert J. Lefkowitz include University of Nice Sophia Antipolis & University of Stuttgart.


Papers
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Journal ArticleDOI
TL;DR: Current efforts to achieve myocardial gene transfer in several model systems are described, with particular emphasis placed on adenovirus-mediated gene delivery, its possibilities, and current limitations.

13 citations

Journal ArticleDOI
TL;DR: Results provide initial evidence that a cyclic phosphorylation-dephosphorylation of rhodopsin can be controlled by the retina-associated protein kinase FA, representing an efficient cyclic cascade mechanism possibly involved in the rapid regulation of r Rhodopsin function in retina.

13 citations

Journal ArticleDOI
01 Jan 1988
TL;DR: The cloning of the genes and the elucidation of the aa sequences for these G-protein coupled receptors should help to determine the structure-function as well as the evolutionary relationship of these proteins.
Abstract: The adenylate cyclase-stimulatory beta 2-adrenergic receptor has been purified to apparent homogeneity from hamster lung. Partial amino acid sequence obtained from isolated CNBr peptides was used to clone the gene and cDNA for this receptor. The predicted amino acid sequence for the hamster beta 2-adrenergic receptor revealed that the protein consists of a single polypeptide chain of 418 aa with consensus N-glycosylation and phosphorylation sites predicted by previous in vitro data. The most striking feature of the receptor protein however, is that it contains seven stretches of hydrophobic residues similar to the proposed seven transmembrane segments of the light receptor rhodopsin. Significant amino acid homology (30-35%) can be found between the hamster beta 2-adrenergic receptor and rhodopsin within these putative membrane spanning regions. Using a hamster beta 2-adrenergic receptor probe, the gene and cDNA for the human beta 2-adrenergic receptor were isolated, revealing a high degree of homology (87%) between the two proteins from different species. Unlike the genes encoding the family of opsin pigments, of which rhodopsin is a member, the genes encoding both hamster and human beta 2-adrenergic receptors are devoid of introns in their coding as well as 5' and 3' untranslated nucleotide sequences. The cloning of the genes and the elucidation of the aa sequences for these G-protein coupled receptors should help to determine the structure-function as well as the evolutionary relationship of these proteins.

12 citations

Journal ArticleDOI
TL;DR: Data are consistent with the notion that some component(s) of the adenylate cyclase system is (are) phosphorylated by protein kinase C, resulting in an enhancement of enzyme activity.
Abstract: Preincubation of frog erythrocyte lysates with tumor-promoting phorbol diesters leads to an increase in adenylate cyclase activity. This stimulatory effect of phorbol diesters was specific. Incubation with 12-O-tctradecanoylphorbol 13-acetate led to increases in basal (38%) and isoproterenol- (40%), fluoride- (25%), and Mn-stimulated (68%) adenylate cyclase activities compared with control. The inactive phorbol diesters (4α-phorbol 12,13-didecanoate and β-phorbol) were ineffective in promoting increases in adenylate cyclase activity. The effect of active phorbol diesters was also observed on isolated frog erythrocyte membranes in the absence of cell supernatant, although to a much lesser extent than in the whole lysates. Addition of the cell supernatant or of purified protein kinase C to the membranes maximized the sensitization by the phorbol diesters. These data are consistent with the notion that some component(s) of the adenylate cyclase system is (are) phosphorylated by protein kinase C, resulting in...

12 citations


Cited by
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28 Jul 2005
TL;DR: PfPMP1)与感染红细胞、树突状组胞以及胎盘的单个或多个受体作用,在黏附及免疫逃避中起关键的作�ly.
Abstract: 抗原变异可使得多种致病微生物易于逃避宿主免疫应答。表达在感染红细胞表面的恶性疟原虫红细胞表面蛋白1(PfPMP1)与感染红细胞、内皮细胞、树突状细胞以及胎盘的单个或多个受体作用,在黏附及免疫逃避中起关键的作用。每个单倍体基因组var基因家族编码约60种成员,通过启动转录不同的var基因变异体为抗原变异提供了分子基础。

18,940 citations

Journal ArticleDOI
19 Feb 1998-Nature
TL;DR: To their surprise, it was found that double-stranded RNA was substantially more effective at producing interference than was either strand individually, arguing against stochiometric interference with endogenous mRNA and suggesting that there could be a catalytic or amplification component in the interference process.
Abstract: Experimental introduction of RNA into cells can be used in certain biological systems to interfere with the function of an endogenous gene Such effects have been proposed to result from a simple antisense mechanism that depends on hybridization between the injected RNA and endogenous messenger RNA transcripts RNA interference has been used in the nematode Caenorhabditis elegans to manipulate gene expression Here we investigate the requirements for structure and delivery of the interfering RNA To our surprise, we found that double-stranded RNA was substantially more effective at producing interference than was either strand individually After injection into adult animals, purified single strands had at most a modest effect, whereas double-stranded mixtures caused potent and specific interference The effects of this interference were evident in both the injected animals and their progeny Only a few molecules of injected double-stranded RNA were required per affected cell, arguing against stochiometric interference with endogenous mRNA and suggesting that there could be a catalytic or amplification component in the interference process

15,374 citations

Journal ArticleDOI
TL;DR: This approach provides two major advantages compared with other available methods: it uses an exact mathematical model of the ligand-binding system, thereby avoiding the possible biases introduced by several commonly used approximations and it uses a statistically valid, appropriately weighted least-squares curve-fitting algorithm with objective measurement of goodness of fit.

8,717 citations

Journal ArticleDOI
13 Oct 2000-Cell
TL;DR: Understanding of the complex signaling networks downstream from RTKs and how alterations in these networks are translated into cellular responses provides an important context for therapeutically countering the effects of pathogenic RTK mutations in cancer and other diseases.

7,056 citations

Journal ArticleDOI
TL;DR: This review considers recent findings regarding GC action and generates criteria for determining whether a particular GC action permits, stimulates, or suppresses an ongoing stress-response or, as an additional category, is preparative for a subsequent stressor.
Abstract: The secretion of glucocorticoids (GCs) is a classic endocrine response to stress. Despite that, it remains controversial as to what purpose GCs serve at such times. One view, stretching back to the time of Hans Selye, posits that GCs help mediate the ongoing or pending stress response, either via basal levels of GCs permitting other facets of the stress response to emerge efficaciously, and/or by stress levels of GCs actively stimulating the stress response. In contrast, a revisionist viewpoint posits that GCs suppress the stress response, preventing it from being pathologically overactivated. In this review, we consider recent findings regarding GC action and, based on them, generate criteria for determining whether a particular GC action permits, stimulates, or suppresses an ongoing stressresponse or, as an additional category, is preparative for a subsequent stressor. We apply these GC actions to the realms of cardiovascular function, fluid volume and hemorrhage, immunity and inflammation, metabolism, neurobiology, and reproductive physiology. We find that GC actions fall into markedly different categories, depending on the physiological endpoint in question, with evidence for mediating effects in some cases, and suppressive or preparative in others. We then attempt to assimilate these heterogeneous GC actions into a physiological whole. (Endocrine Reviews 21: 55‐ 89, 2000)

6,707 citations