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PubMed2026

Alternative transcription of the mouse Gh gene identifies an immune-associated transcript with species-specific structural divergence.

Growth hormone (GH) in mice is primarily expressed in the anterior pituitary, although Gh expression has been reported in extrapituitary tissues, including immune organs. However, the structure of immune-associated Gh transcripts remains poorly characterized. To determine whether splenic Gh transcripts differ from pituitary Gh mRNA, 5'- and 3'-rapid amplification of cDNA ends (RACE) analyses were performed. While 3' RACE showed a shared polyadenylation site, 5' RACE identified a novel exon located approximately 2 kb upstream of the conventional exon 1, generating a transcript (spl-Gh mRNA) with a distinct first exon but shared downstream exons with pituitary Gh mRNA (pit-Gh mRNA). RT-PCR analysis revealed that spl-Gh mRNA is predominantly expressed in immune tissues such as spleen and bone marrow, and its distribution did not correlate with Pit-1 mRNA expression. Quantitative RT-PCR further demonstrated that spl-Gh mRNA was expressed at levels comparable to those of pit-Gh mRNA in the mouse spleen, indicating that spl-Gh is one of the major Gh transcript forms in this tissue. Sequence analysis indicated that spl-Gh mRNA is predicted to retain coding potential for a GH protein. Comparative genomic analyses further demonstrated that genomic features associated with the spl-Gh transcriptional unit are conserved only in a subset of closely related Mus species. In contrast, although a spl-Gh-related transcript was detected in rat spleen, no properly spliced mouse-like transcript was identified under the present experimental conditions. The detected transcript exhibited intron retention and an in-frame stop codon, suggesting that it is unlikely to produce a functional GH protein. These findings identify a distinct immune-associated Gh transcript generated through alternative transcription of the mouse Gh gene and suggest that immune-associated Gh transcriptional mechanisms have undergone species-specific divergence among rodents. Together, these findings reveal previously unrecognized complexity in Gh gene regulation and highlight species-specific differences in immune-associated Gh transcripts.

Animals↗
PubMedDate not supplied

[The reflection of the motivational status in the spectral characteristics of the species-specific acoustic signals of the domestic cat].

Spectral characteristics of species-specific acoustic signals were analyzed in cats under various unfavourable conditions: hunger, isolation, pain stimulation, agony. The increase in the need to get rid of the discomfort accompanied by the development of emotional excitation was reflected in spectral characteristics of produced signals. The frequency and duration of signals increased, their spectrum widened accompanied by spectral maxima shifted towards the high-frequency area similar to the range of formant frequencies in the signals of newborn kittens. The similarity between spectral characteristics of the above signals in adult and newborn cats might indicate the appearance of infantile features in adult cats under conditions of a marked desire to change the existing situation. The fact that motivational state was reflected in spectral characteristics of acoustic signals along with stable responses to the signals, spoke in favour of a considerable contribution made by communication to the organization of intraspecific relations.

Animals↗
PubMed1995

Preferential recognition by human IgE and IgG4 of a species-specific Schistosoma haematobium serine protease inhibitor.

IgE induction in schistosomiasis is an important human response to infection, yet few specific parasite allergens have been characterized. One allergen of Schistosoma haematobium was found to be a species-specific surface antigen and a member of the serine protease inhibitor gene family (SH serpin). The purified recombinant SH serpin protein was used to characterize human isotypic responses to this antigen. Quantitative ELISA based on the recombinant antigen revealed marked IgG4 and IgE responses and a high degree of species specificity (IgG = 96%, IgG4 = 66%, and IgE = 95%) in sera from S. haematobium-infected persons. In contrast, ELISA based on soluble adult worm or egg antigens could not discriminate between species. There was no correlation between serpin-specific IgE and IgG4 levels in 41 infected persons. Further, serpin-induced antibody production in vitro indicated that IgE and IgG4 responses are not coordinately regulated.

Adolescent↗
PubMed2003

Experimental analysis of the processes of systems genesis: expression of the c-fos gene in the chick brain during treatments inducing the development of the species-specific results-of-action acceptor.

The aim of the present work was to identify which parts of the chick brain are activated during treatments inducing the development of the preference to follow a species-specific object (a stuffed chick). Expression of the gene for the transcription factor c-fos was used as the molecular marker for neuron activation. Day-old chicks lacking visual experience were placed for 90 min in a freely rotating squirrel wheel or were subjected to stimulation with a loud noise for 180 min. The animals' preference was tested 24 h after stimulation ended. Both types of stimulation induced the formation of a marked preference to follow the "natural" object in the chicks. c-fos expression was analyzed in sections from the brains of chicks stimulated for 45 min. Increases in the quantity of c-fos mRNA were seen after each type of stimulation in the medial part of the caudal neostriatum. In addition, stimulation in the squirrel wheel was accompanied by high levels of c-fos expression in the paraolfactory lobes, while sound stimulation gave high levels of c-fos expression in the ventral and caudal parts of the archistriatum. These structures of the chick brain are of great interest for studies of the cellular and molecular mechanisms of the formation of the species-specific results-of-action acceptor in the mother-following functional system.

Acoustic Stimulation↗
PubMed1998

Application of multiplex PCR using species-specific primers within the 16S rRNA gene for rapid identification of Nocardioides strains.

For the rapid identification of Nocardioides strains, multiplex PCR, using 16S rDNA as target gene, was used and its value was evaluated. Forward primers specific for Nocardioides albus, Nocardioides jensenii, Nocardioides plantarum and Nocardiodes simplex, among the five validly described Nocardioides species, were designed from the alignment of 165S rDNA sequences. Nocardioides luteus has been shown to be a member of the same species as N. albus by recent molecular systematic studies and preliminary DNA-DNA relatedness tests. Therefore, N. albus and N. luteus were considered as members of the same species in this study. Each primer was found to be species-specific by specificity testing. N. albus NSP01T, N. jensenii NSP19T, N. plantarum NSP21T and N. simplex NSP22T could be clearly differentiated by PCR products characteristics for each species in the multiplex PCR assays. N. luteus gave an identical results to N. albus NSP01. The additional 17 strains of N. albus and the additional four stains of N. simplex gave PCR products identical to those of N. albus NSP01T and N. simplex NSP22T, respectively. Multiplex PCR was found to be rapid, species-specific and reproducible. The technique evaluated in this study proved to be effective for rapidly identifying Nocardioides strains to species level.

Actinomycetales↗
PubMed1999

Interspecies chimeric sperm lysins identify regions mediating species-specific recognition of the abalone egg vitelline envelope.

Abalone sperm lysin is a nonenzymatic, 16-kDa protein that creates a hole in the egg vitelline envelope (VE) through which the sperm swims to fuse with the egg. The dissolution of isolated VE by lysin is species specific. Interspecies comparisons show that the most divergent region of lysin is the N-terminal segment of residues 1-12 which is always species-unique. The C-terminus and three internal segments are moderately variable between species, but not species unique. Analysis of nucleotide substitutions shows that lysin evolves rapidly by positive Darwinian selection, suggesting that there is adaptive value in altering its amino acid sequence. The results reported here, in which segments of lysin were exchanged between two species, prove by direct experimentation that the interspecies variable termini play major roles in the species-specific recognition between sperm lysin and the egg VE.

Acrosome↗
PubMed1997

Identification of the region in yeast S-II that defines species specificity in its interaction with RNA polymerase II.

Yeast S-II was found to stimulate yeast RNA polymerase II only and not mouse RNA polymerase II. To identify the molecular region of S-II that defines species specificity, we constructed six hybrid S-II molecules consisting of three regions from yeast and/or Ehrlich cell S-II and examined their activity in terms of RNA polymerase II specificity and suppression of 6-azauracil sensitivity in the yeast S-II null mutant. We found that the region 132-270 (amino acid positions) of yeast S-II is indispensable for specific interaction with yeast RNA polymerase II in vitro and for suppression of 6-azauracil sensitivity in vivo. The corresponding region of Ehrlich cell S-II, the region 132-262, was also shown to be essential for its interaction with mouse RNA polymerase II. This region is known to be less conserved than the N- and C-terminal regions in the S-II family suggesting that it is important in the interaction with transcription machinery proteins in a tissue and/or species-specific manner.

Amino Acid Sequence↗
PubMed2002

Immunohistochemical study of androgenic gland hormone: localization in the male reproductive system and species specificity in the terrestrial isopods.

Androgenic gland hormone (AGH) is responsible for male sexual differentiation in crustaceans. AGH of the terrestrial isopod, Armadillidium vulgare, is a heterodimetric glycoprotein. To determine the distribution of AGH in the male reproductive system, an immunohistochemical study was carried out using antibodies raised against different components of the proAGH molecule of A. vulgare, for example, the whole molecule of recombinant proAGH expressed in Escherichia coli (E. coli-rAGH), the N-terminal nonapeptide of the B chain, and the N-terminal octapeptide of the A chain. The androgenic gland (AG) showed strong immunoreactivity to all three of these antibodies, while the testis, the seminal vesicle, and the vas deferens did not show immunostaining. To examine the species specificity of AGH, the male reproductive systems in nine species of Oniscidea were examined immunohistochemically with antibody raised against E. coli-rAGH. A positive reaction was observed in the AGs of species belonging to the Armadillidiidae, Porcellionidae, and Scyphacidae families. Immunoreactivity was strongest in A. vulgare and was stronger in Armadillidiidae than in Porcellionidae or in Scyphacidae. These results suggest that structural similarity of AGH may exist among some terrestrial isopods, although AGH seems to harbor a relatively high degree of species specificity.

Animals↗
PubMed1996

Species-specific replication of simian virus 40 DNA in vitro requires the p180 subunit of human DNA polymerase alpha-primase.

Human cell extracts efficiently support replication of simian virus 40 (SV40) DNA in vitro, while mouse cell extracts do not. Since human DNA polymerase alpha-primase is the major species-specific factor, we set out to determine the subunit(s) of DNA polymerase alpha-primase required for this species specificity. Recombinant human, mouse, and hybrid human-mouse DNA polymerase alpha-primase complexes were expressed with baculovirus vectors and purified. All of the recombinant DNA polymerase alpha-primases showed enzymatic activity and efficiently synthesized the complementary strand on an M13 single-stranded DNA template. The human DNA polymerase alpha-primase (four subunits [HHHH]) and the hybrid DNA polymerase alpha-primase HHMM (two human subunits and two mouse subunits), containing human p180 and p68 and mouse primase, initiated SV40 DNA replication in a purified system. The human and the HHMM complex efficiently replicated SV40 DNA in mouse extracts from which DNA polymerase alpha-primase was deleted, while MMMM and the MMHH complex did not. To determine whether the human p180 or p68 subunit was required for SV40 DNA replication, hybrid complexes containing only one human subunit, p180 or p68, together with three mouse subunits (HMMM and MHMM) or three human subunits and one mouse subunit (MHHH and HMHH) were tested for SV40 DNA replication activity. The hybrid complexes HMMM and HMHH synthesized oligoribonucleotides in the SV40 initiation assay with purified proteins and replicated SV40 DNA in depleted mouse extracts. In contrast, the hybrid complexes containing mouse p180 were inactive in both assays. We conclude that the human p180 subunit determines host-specific replication of SV40 DNA in vitro.

Amino Acid Sequence↗
PubMed1984

Production and characterization of species-specific monoclonal antibodies against Leishmania donovani for immunodiagnosis.

Sixteen species-specific monoclonal antibodies were produced against membranes of Leishmania donovani. These antibodies only reacted with determinants present on L. donovani. No cross-reactions were found with any other species of Leishmania or with membranes of Trypanosoma cruzi. An extensive analysis of the binding specificities of selected antibodies was carried out by using whole promastigote homogenates as antigen. Monoclonal antibodies D-1, D-2, D-3, and D-4 correctly identified all 44 L. donovani stocks from a cross-panel of 84 New and Old World Leishmania stocks. Antibodies D-1 and D-2 were also useful for species classification by immunofluorescence. No cross-reactions were observed with any other Leishmania species examined. Based on either Western blot and/or radioimmunoprecipitation analyses, five distinct groups of molecules associated with L. donovani-specific antigenic determinants were identified. These molecules range in m.w. from 18 to 84 kilodaltons. The antigenic molecules recognized by antibodies D-2, D-10, and D-13 are also recognized by antibodies present in sera from patients with visceral leishmaniasis (kala-azar). Kala-azar sera obtained from cases in both the Old and New World specifically compete with these monoclonal antibodies for the appropriate antigenic determinants in Western blot analysis. These monoclonal antibodies and/or the purified protein antigens may be useful in the development of a serologic assay for the clinical diagnosis of visceral leishmaniasis caused by L. donovani and in epidemiologic studies of leishmaniasis.

Animals↗
PubMed2001

Monitoring metastatic behavior of human tumor cells in mice with species-specific polymerase chain reaction: elevated expression of angiogenesis and bone resorption stimulators by breast cancer in bone metastases.

Tumor-stroma interactions are of primary importance in determining the pathogenesis of metastasis. Here, we describe the application of sensitive competitive polymerase chain reaction (PCR) techniques for detection and quantitation of human breast cancer cells (MDA-MB-231) in an in vivo mouse model of experimental metastasis. Human-specific oligonucleotide primers in competitive PCR reactions were used to quantify the amount of MDA-MB-231 cells per tissue per organ. Using this species-specific (semi)quantitative PCR approach, gene expression patterns of (human) tumor cells or (mouse) stromal cells in metastatic lesions in the skeleton or soft tissues were investigated and compared. In all metastatic lesions, MDA-MB-231 cells express angiogenic factors (vascular endothelial growth factors [VEGFs]; VEGF-A, -B, and -C) and bone-acting cytokines (parathyroid hormone-related protein [PTHrP] and macrophage colony-stimulating factor [M-CSF]). In these metastases, PECAM-1-positive blood vessels and stromal cells of mouse origin are detected. The latter express angiogenic factors and markers of sprouting vessels (VEGF receptors flt-1/flk - 1/flk-4 and CD31/PECAM-1). Strikingly, steady-state messenger RNA (mRNA) levels of VEGF-A and -B and the major bone resorption stimulators PTHrP and M-CSF by tumor cells were elevated significantly in bone versus soft tissues (p < or = 0.05, p < or = 0.0001, p < or = 0.001, and p < or = 0.05, respectively), indicating tissue-specific expression of these tumor progression factors. In conclusion, MDA-MB-231 breast cancer cells express a variety of factors in vivo that have been implicated in metastatic bone disease and that correlate with poor survival of patients with breast cancer. We hypothesize that the observed up-regulated expression of angiogenic and bone-resorbing factors by the breast cancer cells in the skeleton underlie the clinically observed osteotropism of breast cancer cells and pathogenesis of osteolytic bone metastases. The application of the species-specific competitive PCR-based assay in vivo can provide new information concerning the involvement of gene families in tumor progression and metastatic disease and greatly facilitates the study of tumor-stroma interactions in cancer invasion and metastasis.

Animals↗
PubMed1993

Species-specific detection of venom antigens from snakes of the Bothrops and Lachesis genera.

Venom-insoluble adsorbents were employed to absorb out the cross-reacting antibodies from monovalent polyclonal antivenoms. The absorbed antivenoms were tested by enzyme-linked immunosorbent assay against homologous and heterologous venoms and showed species-specificity throughout a range of venom concentrations. The same absorbed antisera were used in immunoblots under non-reducing conditions as probes to reveal species-specific antigens. In all cases studied this was achieved. The range of mol. wts of specific antigens was between 20,000 and 120,000, approximately. Venoms added to human serum experimentally were specifically detected by their homologous absorbed antivenom antibodies. The work here described could be important in the development of diagnostic assays for envenomings involving snakes from the Bothrops and Lachesis genera.

Adsorption↗
PubMed1997

Species-specific B-cell epitope on the C-terminal region of the alpha antigen from Mycobacterium scrofulaceum.

In the amino acid (AA) sequences of alpha antigen from mycobacteria, C-terminal regions were variable among a variety of mycobacterial species though the N-terminal regions were relatively conserved. These regions may possess some species-specific antigenic determinants of the alpha antigen from Mycobacterium scrofulaceum (S-alpha). AAs288-300 of S-alpha fused to beta-galactosidase was reactive with the antisera raised against S-alpha. The same fused peptide did not react with the antisera raised against the alpha antigen from Mycobacterium avium (A-alpha) and Mycobacterium bovis BCG (B-alpha). B-cell epitope mapping then was performed focusing on the C-terminal region of S-alpha using the synthetic peptides. Their reactivities with antisera raised against the alpha antigens of three different mycobacterial species were assessed by ELISA. AAs279-286 were a cross-reactive common immunodominant region among three mycobacterial species. This region may be one of the cross-reactive common epitopes in mycobacterial species. And AAs291-300 were reactive only with the antisera raised against S-alpha. This region may possess a species-specific epitope.

Amino Acid Sequence↗
PubMedDate not supplied

Species-specific detection of Leishmania in sandflies using an enzyme-linked immunosorbent assay.

A direct enzyme-linked immunosorbent assay (ELISA) using species-specific monoclonal antibodies was developed for the detection and identification of Leishmania in sandflies. A titration of mock-infected Phlebotomus papatasi showed that fewer than 2000 L. major promastigotes could be detected. The percentage of infected P. papatasi collected in the field, as determined by dissection, was compared to that revealed by the ELISA. Both methods gave similar results, irrespective of whether the flies were caught by sticky papers or light-traps. The percentage of infected flies determined by either method was also similar in experimentally infected colony reared sandflies. The ELISA can be carried out using multiple species-specific antibodies, and is as accurate as identification of infected sandflies by microscopical examination. The technique should be useful for identifying sandfly species involved in transmitting different species of Leishmania, and for rapid assessment of leishmanial infection rates in endemic regions.

Animals↗
PubMed1985

Species specificity in the acceleration of tissue-type plasminogen activator-mediated activation of plasminogens, by fibrinogen cyanogen bromide fragments.

Activation of human plasminogen by human tissue-type plasminogen activator (t-PA) is accelerated in the presence of cyanogen bromide digests of human fibrin(ogen). In the present study a possible species specificity of this phenomenon was investigated. All combinations of the plasminogens, fibrin monomers and cyanogen bromide digests of the fibrinogens of man, pig, rat, cat and monkey (Macaca mulatta), and three t-PA species (man, rat and pig) were studied. No species differences were noted with the fibrin monomers i.e. the activation rate of all five plasminogens increased more than 20-fold in the presence of all five fibrin monomer species, irrespective if man, rat or pig t-PA was used. However, we found that species specificities come to expression when cyanogen bromide digests of the corresponding fibrinogens were used as accelerators. Our results indicate that the plasminogen species and not the source of t-PA or fibrinogen dictates if accelerated activation occurs in the presence of a fibrinogen CNBr digest. The plasminogens can be roughly divided in two groups: --One group, comprising human, monkey and cat plasminogen, which are activated at a higher rate by all three t-PA species in the presence of fibrinogen digest independent on the fibrinogen species from which the digest was prepared. --Another group, comprising pig and rat plasminogen, which is not or only marginally more quickly activated by the 3 t-PA species, irrespective of the fibrinogen species from which the CNBr digest was prepared.

Animals↗
PubMed1991

The sequence of the Arbacia punctulata bindin cDNA and implications for the structural basis of species-specific sperm adhesion and fertilization.

Bindin is the major protein component of the acrosome granule of sea urchin sperm which mediates the species-specific adhesion of sperm to the egg surface during fertilization. Bindin isolated from both Arbacia punctulata and Strongylocentrotus purpuratus sperm demonstrate a distinct adhesive preference for eggs of the same species although a significant amount of cross-species reactivity is observed. Here we describe the isolation and sequence of A. punctulata bindin cDNA clones and a comparison of the predicted protein sequence with the sequence previously reported for S. purpuratus bindin (Gao et al., 1986, Proc. Natl. Acad. Sci., USA 83, 8634-8638). Bindins from these genera show substantial sequence similarity in both the mature bindin domain and the probindin precursor region. The most striking identity is a region of 42 conserved amino acids in the central part of the mature bindins. This conserved domain may be responsible for conserved functions of bindin. Regions flanking this conserved element on both the amino and carboxyl side are more highly divergent, suggesting that they are responsible for the species-specific properties of bindin. The mature A. punctulata sequence contains a putative transmembrane segment between residues 431 and 451 that is absent from S. purpuratus bindin. This structural element may account for the previous observation that isolated A. punctulata bindin uniquely forms multilamellar structures reminiscent of lipid bilayers and binds significant amounts of phospholipid and detergent. The structure of this hydrophobic segment also displays a number of similarities to viral fusion peptides.

Amino Acid Sequence↗
PubMed2001

Species specificity of amidine-based urokinase inhibitors.

Inhibition of the proteolytic activity of urokinase has been shown to inhibit the progression of tumors in rodent models and is being investigated for use in human disease. Understanding the rodent/human species-specificity of urokinase inhibitors is therefore critical for interpretation of rodent cancer progression models that use these inhibitors. We report here studies with a panel of 11 diverse urokinase inhibitors in both human and mouse enzymatic assays. Inhibitors such as amiloride, B428, and naphthamidine, that occupy only the S1 subsite pocket were found to be nearly equipotent between the human and the murine enzymes. Inhibitors that access additional, more distal, pockets were significantly more potent against the human enzyme but there was no corresponding potency increase against the murine enzyme. X-ray crystallographic structures of these compounds bound to the serine protease domain of human urokinase were solved and examined in order to explain the human/mouse potency differences. The differences in inhibitor potency could be attributed to four amino acid residues that differ between murine and human urokinases: 60, 99, 146, and 192. These residues are Asp, His, Ser, and Gln in human and Gln, Tyr, Glu, and Lys in mouse, respectively. Compounds bearing a cationic group that interacts with residue 60 will preferentially bind to the human enzyme because of favorable electrostatic interactions. The hydrogen bonding to residue 192 and steric considerations with residues 99 and 146 also contribute to the species specificity. The nonparallel human/mouse enzyme inhibition observations were extended to a cell-culture assay of urokinase-activated plasminogen-mediated fibronectin degradation with analogous results. These studies will aid the interpretation of in vivo evaluation of urokinase inhibitors.

Amidines↗
PubMed2005

Differential expression of the NRG1 repressor controls species-specific regulation of chlamydospore development in Candida albicans and Candida dubliniensis.

Candida albicans and Candida dubliniensis are opportunistic fungal pathogens that are closely related but differ in their epidemiology and in some phenotypic characteristics, including certain virulence-related traits. A comparison of these two species at the molecular level could therefore provide new insights into the biology and pathogenicity of Candida. Both species share the ability to produce chlamydospores, but only C. dubliniensis forms pseudohyphae with abundant chlamydospores on Staib agar (syn. Guizotia abyssinica creatinine agar), on which C. albicans grows as a budding yeast. To understand the basis of this species-specific, differential regulation of morphogenetic development, we set out to identify C. albicans genes that repress chlamydospore formation under these conditions. A C. albicans genomic library was integrated into the C. dubliniensis genome and transformants were screened for clones in which filamentation and/or chlamydospore production on Staib agar was suppressed. This screen identified two genes, CaNRG1 and CaPDE2, encoding a general transcriptional repressor and a high affinity cAMP phosphodiesterase, respectively. Expression of CaNRG1 in C. dubliniensis repressed pseudohyphae and chlamydospore formation, whereas expression of CaPDE2 only reduced the extent of filamentous growth but did not affect chlamydospore formation. We found that C. dubliniensis, but not C. albicans, specifically downregulates NRG1 expression on Staib medium to allow chlamydospore development. Artificial overexpression of CdNRG1 suppressed pseudohyphal growth and production of chlamydospores in C. dubliniensis. Conversely, deletion of CaNRG1 in C. albicans resulted in chlamydospore formation on Staib agar, confirming its central role in the regulation of this morphogenetic process. Our results demonstrate that differential regulation of a single gene, NRG1, in C. albicans and C. dubliniensis is responsible for their species-specific response to environmental signals that induce chlamydospore development.

Agar↗