Richard Longnecker

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Budding in the yeast Saccharomyces cerevisiae involves a polarized deposition of new cell surface material that is associated with a highly asymmetric disposition of the actin cytoskeleton. Mutants defective in gene CDC24, which are unable to bud or establish cell polarity, have been of great interest with regard to both the mechanisms of cellular(More)
Epstein-Barr virus (EBV) not only induces growth transformation in human B lymphocytes, but has more recently been shown to enhance B cell survival under suboptimal conditions where growth is inhibited; both effects are mediated through the coordinate action of eight virus-coded latent proteins. The effect upon cell survival is best recognized in(More)
Epstein-Barr virus (EBV) is a herpesvirus that is associated with development of malignancies of lymphoid tissue. EBV infections are life-long and occur in >90% of the population. Herpesviruses enter host cells in a process that involves fusion of viral and cellular membranes. The fusion apparatus is comprised of envelope glycoprotein B (gB) and a(More)
Herpesviruses are double-stranded DNA, enveloped viruses that infect host cells through fusion with either the host cell plasma membrane or endocytic vesicle membranes. Efficient infection of host cells by herpesviruses is remarkably more complex than infection by other viruses, as it requires the concerted effort of multiple glycoproteins and involves(More)
In latently infected growth-transformed human lymphocytes, Epstein-Barr virus (EBV) encodes two integral plasma membrane proteins: LMP1, which constitutively induces B-lymphocyte activation and intercellular adhesion, and LMP2A, which associates with LMP1 and is a tyrosine kinase substrate. We now demonstrate that LMP2A associates with src family protein(More)
Epstein-Barr virus (EBV) establishes a persistent latent infection in peripheral B lymphocytes in humans and is associated with a variety of malignancies and proliferative disorders. Latent membrane protein 2A (LMP2A) is one of only two viral proteins expressed in latently infected B lymphocytes in vivo. LMP2A blocks B cell receptor (BCR) signal(More)
The Epstein-Barr virus (EBV) latent membrane protein 2A (LMP2A) blocks B-cell receptor (BCR) signal transduction in EBV-immortalized B lymphocytes in vitro. The cytoplasmic amino-terminal domain of LMP2A contains an immunoreceptor tyrosine activation motif (ITAM). ITAMs consist of paired tyrosine and leucine residues and play a central role in signal(More)
Latent membrane protein 2A (LMP2A) of Epstein-Barr virus (EBV) plays a key role in regulating viral latency and EBV pathogenesis by functionally mimicking signals induced by the B cell receptor (BCR) altering normal B cell development. LMP2A specifically associates with Nedd4 family ubiquitin-protein ligases which downmodulate LMP2A activity by(More)
Earlier reports have described a novel protein kinase in cells infected with herpes simplex or pseudorabies viruses. These novel enzymes were characterized by their acceptance of protamine as a substrate and by their differential chromatographic behavior in anion-exchange chromatography. We report that this activity was not present in extracts of uninfected(More)