Detectable Expression (detectable + expression)

Distribution by Scientific Domains


Selected Abstracts


Cloning and nucleotide sequencing of three heat shock protein genes (hsp90, hsc70, and hsp19.5) from the diamondback moth, Plutella xylostella (L.) and their expression in relation to developmental stage and temperature

ARCHIVES OF INSECT BIOCHEMISTRY AND PHYSIOLOGY (ELECTRONIC), Issue 2 2006
Shoji Sonoda
Abstract Heat shock protein genes, hsp90, hsc70, and hsp19.5, were cloned and sequenced from the diamondback moth, Plutella xylostella (L.) by RT-PCR and RACE method. The cDNA sequence analysis of hsp90 and hsp19.5 revealed open reading frames (ORFs) of 2,151 and 522 bp in length, which encode proteins with calculated molecular weights of 82.4 and 19.5 kDa, respectively. Analysis of cDNA from hsc70 revealed an ORF of 1,878 bp coding a protein with a calculated molecular weight of 69.3 kDa. Furthermore, the analysis of genomic DNA from hsc70 confirmed the presence of introns while no introns were apparent in hsp90 and hsp19.5. Southern blot analysis suggested the presence of multiple copies of each gene family in the DBM genome. Detectable expression of hsp19.5 was observed at the pupal stage while expression of hsp90 and hsc70 was detected at both pupal and adult stages. At adult stage, females showed a higher expression of hsp90 and hsc70 than males. An increased expression was observed in all three genes after exposure to a high temperature in both sexes. These results suggest that in addition to a heat shock response, these HSP genes might be involved in other functions during the course of development in DBM. Arch. Insect Biochem. Physiol. 62:80,90, 2006. © 2006 Wiley-Liss, Inc. [source]


Identification of novel splice variants of the human catalytic subunit c, of cAMP-dependent protein kinase

FEBS JOURNAL, Issue 19 2001
Sigurd Ørstavik
Four different isoforms of the catalytic subunit of cAMP-dependent protein kinase, termed C,, C,, C, and PrKX have been identified. Here we demonstrate that the human C, gene encodes six splice variants, designated C,1, C,2, C,3, C,4, C,4ab and C,4abc. The C, splice variants differ in their N-terminal ends due to differential splicing of four different forms of exon 1 designated exon 1-1, 1-2, 1-3, 1-4 and three exons designated a, b and c. All these exons are located upstream of exon 2 in the C, gene. The previously identified human C, variant has been termed C,1, and is similar to the C, isoform identified in the mouse, ox, pig and several other mammals. Human C,2, which is the homologue of bovine C,2, has no homologue in the mouse. Human C,3 and C,4 are homologous to the murine C,3 and C,2 splice variants, whereas human C,4ab and C,4abc represent novel isofoms previously not identified in any other species. At the mRNA level, the C, splice variants reveal tissue specific expression. C,1 was most abundantly expressed in the brain, with low-level expression in several other tissues. The C,3 and C,4 splice variants were uniquely expressed in human brain in contrast to C,2, which was most abundantly expressed in tissues of the immune system, with no detectable expression in brain. We suggest that the various C, splice variants when complexed with regulatory subunits may give rise to novel holoenzymes of protein kinase A that may be important for mediating specific effects of cAMP. [source]


Detection of elafin as a candidate biomarker for ulcerative colitis by whole-genome microarray screening

INFLAMMATORY BOWEL DISEASES, Issue 9 2006
Carl-Fredrik Flach PhD
Abstract The cause of ulcerative colitis (UC) is largely unknown. Microarray studies are an efficient way of investigating the various genes involved. Here, we have used whole-genome microarrays to clarify the clinical picture and to identify new biomarkers for improved diagnosis. Rectal biopsies were taken from five UC patients and five matched controls, and RNA transcripts were prepared. After labeling, each sample was individually applied to the microarray chips. All transcripts that were more than 10-fold up-regulated in all five patients were analyzed further in seven additional patients and seven controls using quantitative polymerase chain reaction. Of 47,000 transcripts examined, 4 were highly up-regulated in all patients: those encoding elafin, a secreted protease inhibitor, the ion and amino acid transporter B0,+ (SLC6A14), and the metabolic enzyme aldolase B, as well as a recently identified transcript named similar to numb-interacting homolog. The up-regulation of these transcripts appears to follow the progression of the disease because elevated expression was detected in the proximal part of the colon in patients with total colitis but not in patients with left-sided colitis. Immunohistologic examination showed very distinct differences in the expression of elafin. Extensive expression was detected in enterocytes and goblet cells of the affected mucosa, whereas there was no detectable expression in unaffected mucosa and in healthy controls. The results implicate four transcripts and proteins of special interest as possible targets for pharmacologic interference and as biomarkers in UC. Of these, elafin may be of special interest because it is a secreted protein that may be measured in body fluids. [source]


Expression and characterization of ,-glucosidase III in the dwarf honeybee, Apis florea (Hymenoptera: Apoidea: Apidae)

INSECT SCIENCE, Issue 4 2007
CHANPEN CHANCHAO
Abstract Alpha-glucosidase is synthesized in the hypopharyngeal glands located in the head of worker bees including Apis florea. To analyze the developmental stage-specific expression of the ,-glucosidase gene in A. florea, total RNA was isolated from eggs, and the heads of nurse and forager bees. By reverse transcription polymerase chain reaction (RT-PCR), it was shown that the highest expression levels of the ,-glucosidase III gene, in the three examined developmental stadia, were found in forager bees, with much lower expression levels in nurse bees and no detectable expression in eggs. A complete ,-glucosidase III cDNA was obtained by RT-PCR and sequenced. The 1 701 bp cDNA nucleotide sequence and the predicted 567 amino acids it encodes were assayed by BLASTn, BLASTp and BLASTx programs and revealed a 95% and 94% similarity to the A. mellifera,-glucosidase III gene at the DNA and amino acid sequence levels, respectively. For purification of the active encoded enzyme, forager bee heads were homogenized in sodium phosphate buffer solution and the crude extract (0.30 U/mg) sequentially precipitated with 95% saturated ammonium sulfate (0.18 U/mg), and purified by DEAE cellulose ion exchange chromatography (0.17 U/mg), and gel filtration on Superdex 200 (0.52 U/mg). After resolution through sodium dodecyl sulfate-polyacrylamide gel electrophoresis, a single enzymically active band (73 kDa) was identified from renatured substrate gels. Excision of this band, elution of the protein and tryptic peptide digestives identified by matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS) revealed six matching masses to the A. mellifera (Q17958) and predicted A. florea,-glucosidase III protein with 12% coverage, supporting the probable purification of the same ,-glucosidase III protein as that encoded by the cloned cDNA. [source]


Spondylarthritis in HLA,B27/human ,2 -microglobulin,transgenic rats is not prevented by lack of CD8

ARTHRITIS & RHEUMATISM, Issue 7 2009
Joel D. Taurog
Objective HLA,B27 predisposes to spondylarthritis by an unknown mechanism. A logical candidate mechanism is through recognition of B27 by CD8+ T cells. The purpose of this study was to examine the effects of a lack of CD8 on the spondylarthritis that develops in B27/human ,2 -microglobulin (Hu,2m),transgenic rats. Methods A missense mutation in the CD8a gene that causes a loss of CD8, expression was identified in offspring of a male Sprague-Dawley rat that had been treated with the mutagen N -ethyl- N -nitrosourea. The mutation was crossed into B27/Hu,2m-transgenic lines on the Lewis background. CD8a,/, and CD8a+/, progeny were compared on a mixed SD-LEW background as well as after at least 10 backcrosses to LEW rats. CD8 function was assessed by generating cytolytic T lymphocytes (CTLs) against allogeneic DA strain antigens. Results Homozygous mutant rats showed normal CD8a and CD8b messenger RNA levels but no detectable expression of either protein and an almost complete abrogation of the allogeneic CTL response. Two disease phenotypes previously observed in different B27/Hu,2m-transgenic lines also occurred in the respective CD8a,/, -transgenic rat lines. There was no significant difference in disease prevalence or severity between CD8a,/, rats and CD8a+/, rats. Conclusion All of the previously described disease manifestations in HLA,B27/Hu,2m-transgenic rats arise in the absence of any functional CD8+ T cells. It thus seems unlikely that classic T cell recognition of HLA,B27 is of primary importance in this animal model. The possibility of a secondary role of a CD8-dependent mechanism cannot be entirely excluded. [source]


Immunomodulatory activity of a methionine aminopeptidase-2 inhibitor on B cell differentiation

CLINICAL & EXPERIMENTAL IMMUNOLOGY, Issue 3 2009
R. C. Priest
Summary Methionine aminopeptidase-2 (MetAP-2) inhibitors have potent anti-angiogenesis activity and are being developed for the treatment of solid tumours. The recently observed specific expression of MetAP-2 in germinal centre B cells suggests that it has a role in regulating B cell function. We have demonstrated a potent MetAP-2-dependent inhibitory effect on the antibody secretion from B cell receptor and CD40 co-stimulated primary human B cells in the presence of interleukin-21. The effect of MetAP-2 inhibition on antibody secretion was due to a block in differentiation of B cells into plasma cells. Immunohistochemical analysis of germinal centres from human, mouse and marmoset spleen showed a similar expression pattern of MetAP-2 in the marmoset and man, whereas mouse spleen showed no detectable expression. In a marmoset, T dependent immunization model, the MetAP-2 inhibitor suppressed an antigen-specific antibody response. Furthermore, histological analysis showed loss of B cells in the spleen and disrupted germinal centre formation. These results provide experimental evidence to support a novel role for MetAP-2 in immunomodulation. These effects of MetAP-2 are mediated by disruption of the germinal centre reaction and a block in the differentiation of B cells into plasma cells. [source]