The nucleolar protein PICT1 regulates tumor suppressor p53 by tethering ribosomal protein L11 within the nucleolus to repress the binding of L11 to the E3 ligase MDM2. PICT1 depletion results in the release of L11 to the nucleoplasm to inhibit MDM2, leading to p53 activation. Here, we demonstrate that nucleolar stress induces proteasome-mediated degradation of PICT1 in a ubiquitin-independent m...

The giant cholinergic neuron R2 of Aplysia was cultured in combination with identified neurons L11 and R15 and members of a group of left upper quadrant (LUQ) cells L2 to L6 from the abdominal ganglion. All of these neurons receive cholinergic input from other cells in vivo, but not from R2. In vitro, R2 reliably formed unidirectional chemical connections with these cells. Single action potenti...

PURPOSE The authors previously reported a growth-promoting factor, REF-1/TFPI-2, that is specific to retinal pigment epithelial (RPE) cells. The purpose of this study was to determine the genes and proteins of human RPE cells that are altered by exposure to TFPI-2. METHODS Human primary RPE cells were cultured with or without TFPI-2. Cell extracts and isolated RNA were subjected to proteomic ...

Yeast ribosomal proteins L11 and S18 form a dynamic intersubunit interaction called the B1b/c bridge. Recent high resolution images of the ribosome have enabled targeting of specific residues in this bridge to address how distantly separated regions within the large and small subunits of the ribosome communicate with each other. Mutations were generated in the L11 side of the B1b/c bridge with ...

Dickeya chrysanthemi is well known as a plant pathogen that caused major blackleg in the European potato industry in the 1990s. D. chrysanthemi strain L11 was discovered in a recreational lake in Malaysia. Here, we present its draft genome sequence.

The connection of twelve peripheral and divergent dodecyloxy chains to a central tridentate aromatic binding unit provides the dodecacatenar ligand L11, for which room-temperature mesomorphism is detected. An enthalpically unbalanced large melting entropy (DeltaSmL11=226 J mol(-1) K(-1)) results from the programmed microsegregation induced in the crystalline phase, a phenomenon which is maintai...

The homing of lymphocytes from the blood is controlled by specialized processes of lymphocyte-endothelial cell interaction. Interference with these processes offers the potential to manipulate lymphocyte traffic, and thus to modulate normal and pathologic immune and inflammatory responses. We selected antilymphocyte monoclonal antibodies (mAbs) for inhibition of lymphocyte binding in vitro to l...

A panel of six monoclonal antibodies produced against cell surface glycoproteins of a rabbit T lymphocyte line was used with flow cytometry to define rabbit lymphocyte subpopulations. Four thymocyte populations were characterized by size and expression of cell surface antigens and appear to represent stages in thymocyte differentiation. Rabbit spleen contained five subpopulations: two of T line...

During conditions of nutrient deprivation, ribosomes are blocked by uncharged tRNA at the A site. The stringent factor RelA binds to blocked ribosomes and catalyzes synthesis of (p)ppGpp, a secondary messenger that induces the stringent response. We demonstrate that binding of RelA and (p)ppGpp synthesis are inversely coupled, i.e., (p)ppGpp synthesis decreases the affinity of RelA for the ribo...

We report the crystal structure of a 58 nucleotide fragment of 23S ribosomal RNA bound to ribosomal protein L11. This highly conserved ribonucleoprotein domain is the target for the thiostrepton family of antibiotics that disrupt elongation factor function. The highly compact RNA has both familiar and novel structural motifs. While the C-terminal domain of L11 binds RNA tightly, the N-terminal ...