| cell-free synthesis of fish preproinsulin, and processing by heterologous mammalian microsomal membranes. | poly(a)-containing mrna isolated from the islets of langerhans obtained from two species of fish, angler fish (lophius americanus) and sea raven (hemitripterus americanus), stimulated protein synthesis 16-fold in a wheat germ cell-free system. characterization of the translation products by polyacrylamide gel electrophoresis in sodium dodecyl sulfate showed a major polypeptide weighing 11,500 daltons that was specifically precipitated by an antibody against angler fish insulin. partial sequence ... | 1977 | 325565 |
| structural and functional similarity between fish antifreeze proteins and calcium-dependent lectins. | a cdna for a type ii antifreeze protein was isolated from liver of smelt (osmerus mordax). the predicted protein sequence is homologous to that from sea raven (hemitripterus americanus) and both show homology to a family of calcium-dependent lectins. smelt and sea raven belong to taxonomic orders believed to have diverged prior to cenozoic glaciation. thus, type ii antifreeze proteins appear to have evolved independently in these fish species from pre-existing calcium-dependent lectins. sequence ... | 1992 | 1599470 |
| metabolism in sea raven (hemitripterus americanus) hepatocytes: the effects of insulin and glucagon. | the metabolism of the sea raven, hemitripterus americanus, hepatocyte preparation was studied, emphasizing the roles of insulin and glucagon on carbohydrate status. sea raven hepatocyte glycogen was depleted throughout the preincubation and 2-hr incubation period in the presence of either glucose or serine. bovine glucagon stimulated glycogen loss and increased glucose levels and serine flux to glucose. porcine insulin prevented glycogen depletion at least over 1.5 hr of incubation, but did not ... | 1987 | 3108067 |
| evidence for a proprotein intermediate during maturation of type ii antifreeze protein in sea raven, hemitripterus americanus. | the circulating type ii antifreeze protein (afp) in sea raven is 129 amino acids (aa) long (14 kda) and is derived from an initial 163 aa translation product that is synthesised in the liver. signal peptide cleavage algorithms, as well as transgenic expression studies in fall armyworm cells, predict the formation of a 146 aa (16 kda) proprotein intermediate. a protein of this size that cross-reacted with anti-sea raven afp antibody was detected in sea raven serum using phosphate/urea sds-page, a ... | 1996 | 8597578 |
| structure of an antifreeze polypeptide precursor from the sea raven, hemitripterus americanus. | the cystine-rich antifreeze polypeptides (afp) from sea raven were fractionated by reverse-phase high performance liquid chromatography into several components, with sr2 (mr 17,000) as the major afp. sea raven afp cdna clones were isolated from a liver cdna library using a synthetic oligonucleotide, and the identity of one of the clones, c2-1, was confirmed by hybridization selection and cell-free translation. c2-1 encodes a pre-afp of 195 amino acids with no evidence of any profragments. compar ... | 2010 | 3782083 |
| isolation of heat-tolerant myoglobin from asian swamp eel monopterus albus. | myoglobin from asian swamp eel monopterus albus was purified from fish muscle using salt fractionation followed by column chromatography and molecular filtration. the purified mb of 0.68 mg/g wet weight of muscle was determined for its molecular mass by maldi-tof-ms to be 15,525.18 da. using isoelectric focusing technique, the purified mb showed two derivatives with pi of 6.40 and 7.12. six peptide fragments of this protein identified by lc-ms/ms were homologous to mbs of sea raven hemitripterus ... | 2012 | 22538454 |
| evolution of type ii antifreeze protein genes in teleost fish: a complex scenario involving lateral gene transfers and episodic directional selection. | i examined hypotheses about lateral transfer of type ii antifreeze protein (afp) genes among "distantly" related teleost fish. the effects of episodic directional selection on amino acid evolution were also investigated. the strict consensus results showed that the type ii afp and type ii antifreeze-like protein genes were transferred from osmerus mordax to clupea harengus, from the ancestral lineage of the brachyopsis rostratus-hemitripterus americanus clade to the ancestor of the hypomesus nip ... | 2012 | 23032610 |
| killifish opercular skin: a flat epithelium with a high density of chloride cells. | in teleosts the head region, particularly the gills, plays the key role in osmoregulatory nacl transport, presumably by mechanisms located in the chloride cell. as interest has focused on specific mechanisms of chloride cell function, two classical preparations, the intact fish and the isolated, perfused gill, have continued to serve as the only available model systems. however, both of these preparations have severe limitations, e.g., as they are not flat sheets, they cannot be studied readily ... | 1977 | 850116 |
| antifreeze proteins in the urine of marine fish. | several species of marine teleosts have evolved blood plasma antifreeze polypeptides which enable them to survive in ice-laden seawater. four distinct antifreeze protein classes differing in carbohydrate content, amino acid composition, protein sequence and secondary structure are currently known. although all of these antifreezes are relatively small (2.6-33 kd) it was generally thought that they were excluded from the urine by a variety of glomerular mechanisms. in the present study antifreeze ... | 1989 | 24226977 |