Search results for "Cloning"
showing 10 items of 498 documents
Neuroglobins from the Zebrafish Danio rerio and the Pufferfish Tetraodon nigroviridis
2001
Neuroglobin is a recently discovered respiratory, porphyrin-containing protein that is expressed in the brain of mouse and man. Here we show that neuroglobin is also present in the teleost fish. Complete cDNA sequences are reported from the pufferfish Tetraodon nigroviridis and the zebrafish Danio rerio. In addition, the neuroglobin gene of T. nigroviridis was sequenced, demonstrating the conservation of the B12.2, E11.0 and G7.0 introns plus the presence of an additional intron in the 5' noncoding region. The fish neuroglobins each comprise 159 amino acids and are 84.3% identical. Phylogenetic analyses show a basal position of the neuroglobins within the metazoan globin tree. An enhanced a…
Cloning and sequencing of the cDNA encoding human glutaredoxin.
1994
Glutaredoxin (thioltransferase) is a small, heat-stable protein, which is involved in thiol/disulfide exchange reactions. We have isolated a cDNA that encodes glutaredoxin from a human brain cDNA library. The encoded protein contains 106 amino acids with a calculated molecular mass of 11.76 kDa and an isoelectric point of 8.09. The amino acid sequence deduced from the cDNA is more than 80% identical to those of other mammalian glutaredoxins.
A novel member of an ancient superfamily: sponge (Geodia cydonium, Porifera) putative protein that features scavenger receptor cysteine-rich repeats
1997
Proteins featuring scavenger receptor cysteine-rich (SRCR) domains are prominent receptors known from vertebrates and from one phylum of invertebrates, the echinoderms. In the present study we report the first putative SRCR protein from the marine sponge Geodia cydonium (Porifera), a member of the lowest phylum of contemporary Metazoans. Two forms of SRCR molecules were characterized, which apparently represent alternative splicing of the same transcript. The long putative SRCR protein, of 1536 aa, features twelve SRCR repeats, a C-terminal transmembrane domain and a cytoplasmic tail. The sequence of the short form is identical with the long form except that it lacks a coding region near th…
Human fetal adrenal hydroxysteroid sulphotransferase: cDNA cloning, stable expression in V79 cells and functional characterisation of the expressed e…
1995
Dehydroepiandrosterone sulphate (DHEAS) is a major adrenal secretory product, particularly in the fetus where it serves as a substrate for oestrogen biosynthesis by the placenta. The enzyme in the adrenal responsible for synthesising DHEAS, hydroxysteroid sulphotransferase (HST), is therefore essential for human development. We have isolated a full-length cDNA clone, encoding human fetal adrenal HST, and constructed a stable cell line expressing it by transfection into V79 Chinese hamster lung fibroblast cells. This cDNA was essentially identical to that isolated from adult human liver, where the role of HST is less well understood. This recombinant cell line allowed determination of the su…
The 2′-5′-oligoadenylate synthetase in the lowest metazoa: isolation, cloning, expression and functional activity in the sponge Lubomirskia baicalens…
2007
Aquatic animals, especially filter feeders such as sponges [phylum Porifera], are exposed to a higher viral load than terrestrial species. Until now, the antiviral defense system in the evolutionary oldest multicellular organisms, sponges, is not understood. One powerful protection of vertebrates against virus infection is mediated by the interferon (IFN)-inducible 2'-5'-oligoadenylate synthetase [(2-5)A synthetase] system. In the present study we cloned from the freshwater sponge Lubomirskia baicalensis a cDNA encoding a 314 aa long ORF with a calculated size of 35748Da, a putative (2-5)A synthetase, and raised antibodies against the recombinant protein. The native enzyme was identified in…
Increased Expression of Integrin and Receptor Tyrosine Kinase Genes During Autograft Fusion in the SpongeGeodia cydonium
1999
Recently cDNAs coding for cell surface molecules have been isolated from sponges. The molecules for alpha-integrin, galectin, and receptor tyrosine kinase (RTK), obtained from the marine sponge, Geodia cydonium, have been described earlier. In the present study also the cDNA for one putative beta-integrin has been identified from G. cydonium. The deduced aa sequence comprises the characteristic signatures, found in other metazoan beta-integrin molecules; the estimated size is 95,215 Da. To obtain first insights into the molecular events which proceed during autograft fusion, the expressions of these genes were determined on transcriptional and translational level. The cDNAs as well as antib…
Evolutionary relationships of Metazoa within the eukaryotes based on molecular data from Porifera
1999
Recent molecular data provide strong support for the view that all metazoan phyla, including Porifera, are of monophyletic origin. The relationship of Metazoa, including the Porifera, to Plantae, Fungi and unicellular eukaryotes has only rarely been studied by using cDNAs coding for proteins. Sequence data from rDNA suggested a relationship of Porifera to unicellular eukaryotes (choanoflagellates). However, ultrastructural studies of choanocytes did not support these findings. In the present study, we compared amino acid sequences that are found in a variety of metazoans (including sponges) with those of Plantae, Fungi and unicellular eukaryotes, to obtain an answer to this question. We use…
Experimental indication in favor of the introns-late theory: the receptor tyrosine kinase gene from the sponge Geodia cydonium.
1997
Abstract We have analyzed the gene that encodes receptor tyrosine kinase (RTK) from the marine sponge Geodia cydonium, which belongs to the most ancient and simple metazoan groups, the Porifera. RTKs are enzymes found only in metazoa. The sponge gene contains two introns in the extracellular part of the protein. However, the rest of the protein (transmembrane and intracellular part), including the tyrosine kinase (TK)-domain, is encoded by a single exon. In contrast, all TK genes, so far known only from higher animals (vertebrates), contain several introns especially in the TK-domain. The TK-domain of G. cydonium shows similarity with numerous members of receptor as well as nonreceptor TKs.…
Molecular cloning of a tyrosine kinase gene from the marine spongeGeodia cydonium: a new member belonging to the receptor tyrosine kinase class II fa…
1994
We have isolated and characterized a cDNA from the marine sponge Geodia cydonium coding for a new member of the tyrosine protein kinase (TK) family. The cDNA encodes a protein of M(r) = 68,710, termed GCTK, which is homologous to class II receptor tyrosine kinases (RTKs). GCTK contains conserved amino acids (aa) characteristic of all protein kinases, and the sequences DLATRN and PIRWMATE which are highly specific for TKs. Furthermore, the sequence N-L-Y-x(3)-Y-Y-R is highly homologous to the sequence D-[LIV]-Y-x(3)-Y-Y-R found only in class II RTKs. The sponge TK, when compared with mammalian class II RTKs, shows maximum 31% homology in the TK domain indicating that this the oldest member o…
Tonoplast subcellular localization of maize cytochrome b5 reductases
2000
Plant cytochrome b 5 reductases (b 5 R) are assumed to be part of an ER-associated redox chain that oxidizes NADH to provide electrons via cytochrome b5 (cyt b 5 ) to ER-associated fatty acyl desaturase and related hydroxylases, as in mammalian cells. Here we report on cDNA cloning of a novel maize b 5 R, NFR II, strongly related to a previously cloned cDNA, NFR I (Bagnaresi et al., 1999, Biochem, J. 338, 499-5051. Maize b 5 R isoforms are produced by a small multi-gene family. The NFR cDNAs were shown to encode active b 5 Rs by heterologous expression in yeast. Both reductases, in addition to Fe 3+ -chelates, efficiently reduced Cu 2+ -chelates. Using a polyclonal antibody able to recogniz…