Search results for "isoform"

H2-Mβ1 and H2-Mβ2 Heterodimers Equally Promote CLIP Removal in I-Aq Molecules from Autoimmune-prone DBA/1 Mice

2001

Antigen-presenting cells degrade endocytosed antigens, e.g. collagen type II, into peptides that are bound and presented to arthritogenic CD4(+) helper T cells by major histocompatibility complex (MHC) class II molecules. Efficient loading of many MHC class II alleles with peptides requires the assistance of H2-M (HLA-DM in humans), a heterodimeric MHC class II-like molecule that facilitates CLIP removal from MHC class II molecules and aids to shape the peptide repertoire presented by MHC class II to CD4(+) T cells. In contrast to the HLA-DM region in humans, the beta-chain locus is duplicated in mice, with the H2-Mb1 beta-chain distal to H2-Mb2 and the H2-Ma alpha-chain gene. H2-M alleles …

Oxidative inactivation of mitochondrial creatine kinase: Differential sensitivity of isoforms

2010

Expression analysis and functional activity of interleukin-7 splice variants.

2008

Alternative splicing results in multiple protein isoforms derived from a single gene. The magnitude of this process ranges from a complete loss of function to gain of new function. We examined, as a paradigm, alternative splicing of the non-redundant human cytokine, interleukin-7 (IL-7). We show that extensive IL-7 splicing in human tissues of different histology, including MTB+ granuloma lesions, transformed tissue and tumor cell lines. IL-7 splice variants were expressed as recombinant proteins. A differentially spliced IL-7 isoform, lacking exon 5, leads to STAT-5 phosphorylation in CD4+ and CD8+ T cells, promotes thymocyte maturation and T-cell survival. Human tumor lesions show aberran…

RNA-binding activity of the rat calmodulin-binding PEP-19 protein and of the long PEP-19 isoform

2012

Synthesis of H1˚ histone protein, in the developing rat brain, seems to be regulated mainly at the post-transcriptional level. Since regulation of RNA metabolism depends on a series of RNA-binding proteins, we have been searching for RNA-binding proteins involved in the post-transcriptional regulation of the H1˚ gene. We recently reported isolation, from a cDNA expression library, of an insert encoding a novel protein, the C-terminal half of which is identical to that of PEP-19, a brain-specific protein involved in calcium metabolism. The novel protein was called long PEP-19 isoform (LPI). Herein we show that LPI, as well as PEP-19, can bind H1˚ RNA. Moreover, in order to improve production…

NAIP-deltaEx10-11: a novel splice variant of the apoptosis inhibitor NAIP differently expressed in drug-sensitive and multidrug-resistant HL60 leukem…

2002

Alterations of neuronal apoptosis inhibitory protein (NAIP), a member of the inhibitory of apoptosis protein (IAP) family of inhibitors of apoptosis, have been previously associated with different neurodegenerative disorders. This study indicated the existence of a novel NAIP splice variant. This isoform, NAIP-deltaEx10-11, was found in tumor cell lines of different origin and in normal adult brain. Analysis of the putative protein predicted that the NAIP variant lacks part of the third BIR domain as well as the COOH-terminal tail of regular NAIP. This might suggest that it is endowed with a reduced antiapoptotic activity. This view is supported by the fact that NAIP-deltaEx10-11 mRNA and p…

Serological identification and expression analysis of gastric cancer-associated genes

2002

Serological identification of tumour antigens by recombinant expression cloning has proved to be an effective strategy for the identification of cancer-associated genes having a relevance to cancer aetiology and progression, and for defining possible targets for immunotherapeutic intervention. In the present study we applied this technique to identify immunogenic proteins for gastric cancer that resulted in isolation of 14 distinct serum-reactive antigens. In order to evaluate their role in tumourigenesis and assess the immunogenicity of the identified antigens, we characterised each cDNA clone by DNA sequence analysis, mRNA tissue distribution, comparison of mRNA levels in cancerous and ad…

Developmental expression of two Haliotis asinina hemocyanin isoforms

2005

Hemocyanins are large copper-containing respiratory proteins that play a role in oxygen transport in many molluscs. In some species only one hemocyanin isoform is present while in others two are expressed. The physiological relevance of these isoforms is unclear and the developmental and tissue-specific expression of hemocyanin genes is largely unknown. Here we show that two hemocyanin genes in the gastropod Haliotis asinina, which encode H. asinina hemocyanin (HaH1) and HaH2 isoforms, are developmentally expressed. These genes initially are expressed in a small number of mesenchyme cells at trochophore and pre-torsional veliger stages, with HaH1 expression slightly preceding HaH2. These ce…

Muscleblind isoforms are functionally distinct and regulate α-actinin splicing

2007

Drosophila Muscleblind (Mbl) proteins control terminal muscle and neural differentiation, but their molecular function has not been experimentally addressed. Such an analysis is relevant as the human Muscleblind-like homologs (MBNL1-3) are implicated in the pathogenesis of the inherited muscular developmental and degenerative disease myotonic dystrophy. The Drosophila muscleblind gene expresses four protein coding splice forms (mblA to mblD) that are differentially expressed during the Drosophila life cycle, and which vary markedly in their ability to rescue the embryonic lethal phenotype of muscleblind mutant flies. Analysis of muscleblind mutant embryos reveals misregulated alternative sp…

Aberrantly activated claudin 6 and 18.2 as potential therapy targets in non-small-cell lung cancer

2014

Claudins (CLDNs) are central components of tight junctions that regulate epithelial-cell barrier function and polarity. Altered CLDN expression patterns have been demonstrated in numerous cancer types and lineage-specific CLDNs have been proposed as therapy targets. The objective of this study was to assess which fraction of patients with non-small-cell lung cancer (NSCLC) express CLDN6 and CLDN18 isoform 2 (CLDN18.2). Protein expression of CLDN6 and CLDN18.2 was examined by immunohistochemistry on a tissue microarray (n=355) and transcript levels were supportively determined based on gene expression microarray data from fresh-frozen NSCLC tissues (n=196). Both were analyzed with regard to …

Intronic promoters and their noncoding transcripts: A new source of cancer-associated genes

2012

Recent studies of mammalian genomes suggest that alternative promoters are associated with various disorders, including cancer. Here we present an intronic promoter of the murine proteinase 3 gene, which drives the expression of an alternative mRNA in intron 2 of the prtn3 gene. The proximal promoter sequences were identified and a series of promoter deletion constructs were used to identify the sequence elements that are required for basal promoter activity. Expression of the homeobox transcription factor CUX1 p75 isoform was found to suppress the activity of the alternative PR3 promoter. Data base analyses, multiple alignments and expression data showed that the intronic PR3 promoter is a…