Alphonse García

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The Axl receptor tyrosine kinase was identified as a protein encoded by a transforming gene from primary human myeloid leukaemia cells by DNA-mediated transformation of NIH 3T3 cells. Axl is the founding member of a family of related receptors that includes Eyk, encoded by a chicken proto-oncogene originally described as a retroviral transforming gene, and(More)
Bcl-xL and Bcl-w specifically interact with PP1alpha and Bad. A phosphatase activity sensitive to okadaic acid was detected in Bcl-xL, Bcl-w and Bad immunoprecipitates. Serine phosphorylation of Bcl-xL and Bcl-w correlates with the number of trimolecular complexes formed. Depletion of Bcl-xL and Bcl-w decreases the remaining Bad-associated phosphatase(More)
The reversible phosphorylation of proteins controlled by protein kinases and protein phosphatases is a major mechanism that regulates a wide variety of cellular processes. In contrast to C. elegans, recent studies in mammalian cells have highlighted a major role of serine/threonine protein phosphorylation in apoptosis. To illustrate the importance of(More)
Entry into mitosis is a highly regulated process, promoted by the activated Cyclin B1/Cdk1 complex. Activation of this complex is controlled, in part, by the protein kinase Aurora-A, which is a member of a multigenic serine/threonine kinase family. In normal cells, Aurora-A activity is regulated, at least in part, by degradation through the(More)
Protein phosphatase 1 is regulated by the interaction between a catalytic subunit (PP1c) and multiple interacting proteins that allow the specific dephosphorylation of diverse cellular targets. This communication proposes to use the simultaneous presence of distinct consensus PP1c docking motifs R/K-x(0,1)-V-x-F and F-x-x-R/K-x-R/K as a signature to(More)
BACKGROUND The hallmark of HIV-1 pathogenesis is the progressive CD4(+) T cell depletion and high propensity of CD4(+) T cells to apoptosis. HIV-1 viral protein R (Vpr) is a major pro-apoptotic gene product. A first Vpr-mediated apoptotic mechanism that requires a physical interaction of HIV-1 Vpr(71-82) mitochondriotoxic domain containing the conserved(More)
T. annulata, an intracellular pathogenic parasite of the Aplicomplexa protozoan family infects bovine B-lymphocytes and macrophages. Parasitized cells that become transformed survive and proliferate independently of exogenous growth factors. In the present study, we used the isogenic non parasitized BL3 and parasitized TBL3 B cell lines, as a model to(More)
BACKGROUND Previous studies established that PP1 is a target for Bcl-2 proteins and an important regulator of apoptosis. The two distinct functional PP1 consensus docking motifs, R/Kx((0,1))V/IxF and FxxR/KxR/K, involved in PP1 binding and cell death were previously characterized in the BH1 and BH3 domains of some Bcl-2 proteins. PRINCIPAL FINDINGS In(More)
The molecular recognition of specific transfer RNAs by the appropriate aminoacyl-tRNA synthetase is an important step in determining the accuracy of translation of the genetic message from nucleic acids into proteins. Recent studies using variant tRNAs with specific sequence modifications have indicated particular regions that determine their identity. Here(More)
A synthetic gene of yeast aspartic acid tRNA with a promoter for phage T7 RNA polymerase was cloned in Escherichia coli. The in vitro transcribed tRNA(Asp) molecules are deprived of modified nucleotides and retain their aspartylation capacity. The solution conformation of these molecules was mapped with chemical structural probes and compared to that of(More)