Publications by authors named "Daniel E Holloway"

Angiogenin (hANG), a member of the Ribonuclease A superfamily has angiogenic, neurotrophic and neuroprotective activities. Mutations in hANG have been found in patients with Amyotrophic lateral sclerosis (ALS). The zebrafish (Danio rerio) rnasel-1, 2 and 3 are orthologues of hANG and of these only Rnasel-1 and Rnasel-2 have been shown to be angiogenic.

View Article and Find Full Text PDF

Angiogenin (Ang) is a potent inducer of neovascularization. Point mutations in human Ang have been linked to cancer progression and two neurodegenerative diseases: amyotrophic lateral sclerosis and Parkinson's disease. Intensive structural and functional analyses of Ang have been paramount in assigning functions to this novel homologue of bovine pancreatic RNase A.

View Article and Find Full Text PDF

Onconase(®) (ONC) is an amphibian member of the pancreatic ribonuclease superfamily that is selectively toxic to tumor cells. It is a much less efficient enzyme than the archetypal ribonuclease A and, in an attempt to gain further insight, we report the first atomic resolution crystal structure of ONC, determined in complex with sulfate ions at 100 K. The electron density map is of a quality sufficient to reveal significant nonplanarity in several peptide bonds.

View Article and Find Full Text PDF

Ribonuclease A is the archetype of a functionally diverse superfamily of vertebrate-specific ribonucleases. Inhibitors of its action have potential use in the elucidation of the in vivo roles of these enzymes and in the treatment of pathologies associated therewith. Derivatives of adenosine 5'-pyrophosphate are the most potent nucleotide-based inhibitors known.

View Article and Find Full Text PDF

The widespread and functionally varied members of the ribonuclease A (RNase A) superfamily provide an excellent opportunity to study evolutionary forces at work on a conserved protein scaffold. Representatives from the zebrafish are of particular interest as the evolutionary distance from non-ichthyic homologues is large. We conducted an exhaustive survey of available zebrafish DNA sequences and found significant polymorphism among its four known homologues.

View Article and Find Full Text PDF

Besides Onconase (ONC) and its V11/N20/R103-variant, oocytes of the Northern Leopard frog (Rana pipiens) contain another homologue of ribonuclease A, which we named Amphinase (Amph). Four variants (Amph-1-4) were isolated and sequenced, each 114 amino acid residues in length and N-glycosylated at two positions. Sequence identities (a) among the variants and (b) versus ONC are 86.

View Article and Find Full Text PDF

Murine angiogenin-4 (mAng-4) is a member of the pancreatic ribonuclease superfamily that is expressed in some endodermally derived organs. We now show that mAng-4 is angiogenic using a thoracic aorta assay never before applied to the angiogenins. mAng-4, human angiogenin (hAng), and murine angiogenin-1 (mAng-1) stimulate the proliferation of IGR1 melanoma cells but do not stimulate the proliferation or migration of bovine corneal endothelial cells or primary mouse embryonic fibroblasts.

View Article and Find Full Text PDF

Eosinophil-derived neurotoxin (EDN) is a catalytically proficient member of the pancreatic ribonuclease superfamily secreted along with other eosinophil granule proteins during innate host defense responses and various eosinophil-related inflammatory and allergic diseases. The ribonucleolytic activity of EDN is central to its antiviral and neurotoxic activities and possibly to other facets of its biological activity. To probe the importance of this enzymatic activity further, specific inhibitors will be of great aid.

View Article and Find Full Text PDF

Angiogenin is an unusual member of the pancreatic ribonuclease superfamily that induces blood-vessel formation and is a promising anticancer target. The three-dimensional structure of murine angiogenin (mAng) has been determined by X-ray crystallography. Two structures are presented: one is a complex with sulfate ions (1.

View Article and Find Full Text PDF

Placental ribonuclease inhibitor (RI) binds diverse mammalian RNases with dissociation constants that are in the femtomolar range. Previous studies on the complexes of RI with RNase A and angiogenin revealed that RI utilises largely distinctive interactions to achieve high affinity for these two ligands. Here we report a 2.

View Article and Find Full Text PDF

C3 exoenzyme from Clostridium botulinum (C3bot1) ADP-ribosylates and thereby inactivates Rho A, B and C GTPases in mammalian cells. The structure of a tetragonal crystal form has been determined by molecular replacement and refined to 1.89 A resolution.

View Article and Find Full Text PDF

Human angiogenin (Ang) is a potent inducer of blood vessel formation and is a member of the pancreatic ribonuclease superfamily. Its enzymatic activity is unusually weak and biased toward cleavage after cytidine nucleotides. As part of an ongoing investigation into the structural basis of Ang's characteristic activity, we have determined the crystal structures of three Ang variants having novel activity.

View Article and Find Full Text PDF

The C3stau2 exoenzyme from Staphylococcus aureus is a C3-like ADP-ribosyltransferase that ADP-ribosylates not only RhoA-C but also RhoE/Rnd3. In this study we have crystallized and determined the structure of C3stau2 in both its native form and in complex with NAD at 1.68- and 2.

View Article and Find Full Text PDF

We have determined the structure of wild-type IP-10 from three crystal forms. The crystals provide eight separate models of the IP-10 chain, all differing substantially from a monomeric IP-10 variant examined previously by NMR spectroscopy. In each crystal form, IP-10 chains form conventional beta sheet dimers, which, in turn, form a distinct tetrameric assembly.

View Article and Find Full Text PDF

Angiogenin and ribonuclease A share 33% sequence identity but have distinct functions. Angiogenin is a potent inducer of angiogenesis that is only weakly ribonucleolytic, whereas ribonuclease A is a robust ribonuclease that is not angiogenic. A chimera ("ARH-I"), in which angiogenin residues 58-70 are replaced with residues 59-73 of ribonuclease A, has intermediate ribonucleolytic potency and no angiogenic activity.

View Article and Find Full Text PDF

Human eosinophil-derived neurotoxin (EDN) is a small, basic protein that belongs to the ribonuclease A superfamily. EDN displays antiviral activity and causes the neurotoxic Gordon phenomenon when injected into rabbits. Although EDN and ribonuclease A have appreciable structural similarity and a conserved catalytic triad, their peripheral substrate-binding sites are not conserved.

View Article and Find Full Text PDF