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PubMed2002

Aspergillus nidulans polarity mutant swoA is complemented by protein O-mannosyltransferase pmtA.

Previously swoA was identified in Aspergillus nidulans as a single locus, temperature-sensitive (ts) mutant aberrant in polarity maintenance. swoA was complemented by transformation with a plasmid genomic library. The sequence of the complementing gene was identical to a previously submitted GenBank sequence for pmtA, a protein O-mannosyltransferase. The pmtA/swoA-2 gene hybridized to three cosmids that are located on chromosome V and the swoA mutation was mitotically mapped to chromosome V. PMTs are endoplasmic reticulum-resident proteins responsible for the first step of O-glycosylation. Structural predictions suggest that PmtA contains seven membrane spans similar to PMTs from Saccharomyces cerevisiae and other organisms. Phylogenetic analysis indicates that PmtA is most closely related to the S. cerevisiae sub-family of PMTs containing Pmt2, Pmt3 and Pmt6. The mutant pmtA/swoA-2 locus contained a lesion that changed Y662 to a stop codon, eliminating the final membrane spanning domain and interrupting a domain essential for function in other PMTs.

Amino Acid Sequence↗

PubMed2002

Cloning and transcription analysis of the Aspergillus aculeatus No. F-50 endoglucanase 2 (cmc2) gene.

The cmc2 gene, coding for an endoglucanase 2 (CMC2) of Aspergillus aculeatus, was cloned using both genomic and cDNA libraries, and sequenced. The gene consists of 1230 bp encoding a protein of 410 amino acid residues with a molecular mass of 43,697 Da. The CMC2, composed of an N-terminal catalytic domain belonging to the family 5 of glycosyl hydrolases and a C-terminal cellulose-binding domain (CBD) belonging to the family I of CBDs, showed identity with other fungal endoglucanases, particularly with that of A. niger, A. nidulans, A. kawachii and A. aculeatus. The transcription of the cmc2 gene in A. aculeatus cells that were grown on different carbon sources was measured. Analysis by the ribonuclease protection assay revealed that expression of the cmc2 gene is induced by cellulose and some disaccharides and repressed by glucose.

Journal Article↗

PubMed1992

Pig apolipoprotein R: a new member of the short consensus repeat family of proteins.

Apolipoprotein R (apoR) is a 23-kDa protein found on very low-density lipoprotein (VLDL), on chylomicrons, and in the d > 1.21 g/mL fraction of pig plasma. The plasma concentration of apoR is 5.1 micrograms/mL, with 11.5% of apoR found on VLDL. In vitro, apoR can transfer from the d > 1.21 g/mL infranatant onto artificial lipid emulsions or human chylomicrons but not onto human VLDL. An apoR cDNA was isolated from a pig liver lambda gt11 expression library. DNA sequence analysis of the apoR cDNA revealed 67% identity with the 3'-terminal region of human C4b-binding protein alpha-chain cDNA (C4BP alpha). C4BP alpha is a 70-kDa glycoprotein that regulates both the coagulation and the complement cascades. In plasma, C4BP alpha exists as disulfide-linked multimers consisting of seven C4BP alpha chains and a single C4BP beta chain. Like C4BP, apoR forms high molecular weight disulfide-linked complexes in plasma. However, unlike C4BP alpha, apoR complexes do not appear to contain C4BP beta. ApoR mRNA was detected in pig liver, spleen, lung, bone marrow, and lymph node, but was absent in intestine and white blood cells. This distribution is consistent with the production of apoR in terminally differentiated macrophages but not in blood monocytes. ApoR mRNA was not detected in RNA isolated from human liver or lung. ApoR may be a lipoprotein-borne regulator of either the coagulation or the complement cascades.

Amino Acid Sequence↗

PubMed1989

Structure of the human thyroid peroxidase gene: comparison and relationship to the human myeloperoxidase gene.

All exons of the human thyroid peroxidase gene were cloned from phage and cosmid libraries and sequenced, including 2599 base pairs of upstream DNA. The gene contains 17 exons and covers at least 150 kilobase pairs of chromosome 2. The transcription start site was identified by both S1 mapping and primer extension; a typical TATA box was found 25 bases upstream of the putative start site. A comparison of the gene structures of thyroid peroxidase and a granulocyte protein, myeloperoxidase, revealed that the positions of the 3rd through 11th exon-intron junctions in thyroid peroxidase coincide exactly with those of the 2nd through 11th exon-intron junctions in myeloperoxidase except the 7th myeloperoxidase junction, that does not have any counterpart in thyroid peroxidase. The amino acid codon separation pattern in each junction is well conserved between both enzymes. Four exons, unique to thyroid peroxidase, are located at the 3' end of the gene (exons 13-16), each of which encompasses a different protein module. Three of these modules, representing exons 13, 14, and 15, bear significant similarities to C4b-beta 2 glycoprotein, the EGF-LDL receptor, and a typical transmembrane domain, respectively. The genes coding for these modules were probably fused to an ancestral peroxidase gene to generate the present thyroid peroxidase gene. The data suggest that intron loss, and/or insertion, and exon shuffling have played important roles in the evolution of the thyroid peroxidase gene.

Amino Acid Sequence↗

PubMed1990

A shared internal threonine-glutamic acid-threonine-proline repeat defines a family of Dictyostelium discoideum spore germination specific proteins.

A cDNA denoted pRK270 hybridizes to two mRNA species in RNA blots. The mRNAs specific to this clone are not expressed during vegetative growth and multicellular development. They are, however, found predominantly during early stages of spore germination, suggesting that their synthesis is rapidly and coordinately turned on during germination. Two different cDNAs named 270-6 and 270-11 were isolated, representing the two mRNAs. DNA blot analysis shows that 270 is a multigene family. Four genes were isolated from Dictyostelium genomic libraries and sequenced. The putative proteins coded for by these genes are about 51,000, 55,000, 76,000, and 100,000 Da. Two of the genes are expressed during spore germination while transcripts for the other two are not present during spore germination, vegetative growth, or the stages of multicellular development studied. The cDNAs and genes code for deduced proteins that possess a very unusual internal amino acid repeat comprised of the tetrapeptide threonine-glutamic acid-threonine-proline. The other portions of the proteins have no homology among themselves. The 270-6 protein shows excellent identity with avocado (Persea americana) cellulase, indicating that it may function as an endo-(1,4)-beta-D-glucanase.

Amino Acid Sequence↗

PubMed1999

The RRM domain of MINT, a novel Msx2 binding protein, recognizes and regulates the rat osteocalcin promoter.

Msx2 is a homeodomain transcriptional repressor that exerts tissue-specific actions during craniofacial skeletal and neural development. To identify coregulatory molecules that participate in transcriptional repression by Msx2, we applied a Farwestern expression cloning strategy to identify transcripts encoding proteins that bind Msx2. A lambdagt11 expression library from mouse brain was screened with radiolabeled GST-Msx2 fusion protein encompassing the core suppressor domain of Msx2. A cDNA was isolated that encodes a novel protein fragment that binds radiolabeled Msx2. Homeoprotein binding activity was confirmed by Farwestern analysis of the T7-epitope-tagged recombinant protein fragment, and interactions in vitro require Msx2 residues necessary for transcriptional suppression in vivo. On the basis of biochemical analyses, this novel protein was named MINT, an acronym for Msx2-interacting nuclear target protein. The original clone is part of a 12.6 kb transcript expressed at high levels in testis and at lower levels in calvarial osteoblasts and brain. Multiple clones isolated from a mouse testis library were sequenced to construct a MINT cDNA contig of 11 kb. Starting from an initiator Met in good Kozak context, a large nascent polypeptide of 3576 amino acids is predicted, in contiguous open reading frame with the Msx2 interaction domain residues 2070-2394. Protein sequence analysis reveals that MINT has three N-terminal RNA recognition motifs (RRMs) and four nuclear localization signals. Western blot analysis of fractionated cell extracts reveals that mature approximately 110 kDa (N-terminal) and approximately 250 kDa (C-terminal) MINT protein fragments accumulate in chromatin and nuclear matrix fractions, cosegregating with Msx2 and topoisomerase II. In gel shift assays, the MINT RRM domain selectively binds T- and G-rich DNA sequences; this includes a large G/T-rich inverted repeat element present in the proximal rat osteocalcin (OC) promoter, overlapping three cognates that support OC expression in osteoblasts. MINT and OC mRNAs are reciprocally regulated during differentiation of MC3T3E1 calvarial osteoblasts. Consistent with its proposed role as a nuclear transcriptional factor, transient expression of MINT(1-812) suppresses the FGF/forskolin-activated OC promoter, does not significantly regulate CMV promoter activity, but markedly upregulates the HSV thymidine kinase promoter in MC3T3E1 cells. In toto, these data indicate that the novel nuclear protein MINT binds the homeoprotein Msx2 and coregulates OC during craniofacial development. Msx2 and MINT both target an information-dense, osteoblast-specific regulatory region of the OC proximal promoter, nucleotides -141 to -111. The N-terminal MINT RRM domain represents an authentic dsDNA binding module for this novel vertebrate nuclear matrix protein. Acting as a scaffold protein, MINT potentially exerts both positive and negative regulatory actions by organizing transcriptional complexes in the nuclear matrix.

Amino Acid Sequence↗

PubMed2006

Development of the GENIPOL European flounder (Platichthys flesus) microarray and determination of temporal transcriptional responses to cadmium at low dose.

We have constructed a high density, 13 270-clone cDNA array for the sentinel fish species European flounder (Platichthys flesus), combining clones from suppressive subtractive hybridization and a liver cDNA library; DNA sequences of 5211 clones were determined. Fish were treated by single intraperitoneal injection with 50 micrograms cadmium chloride per kilogram body weight, a dose relevant to environmental exposures, and hepatic gene expression changes were determined at 1, 2, 4, 8, and 16 days postinjection in comparison to saline-treated controls. Gene expression responses were confirmed by real-time reverse transcription polymerase chain reaction (RT-PCR). Blast2GO gene ontology analysis highlighted a general induction of the unfolded protein response, response to oxidative stress, protein synthesis, transport, and degradation pathways, while apoptosis, cell cycle, cytoskeleton, and cytokine genes were also affected. Transcript levels of cytochrome P450 1A (CYP1A) were repressed and vitellogenin altered, real-time PCR showed induction of metallothionein. We thus describe the establishment of a useful resource for ecotoxicogenomics and the determination of the temporal molecular responses to cadmium, a prototypical heavy metal pollutant.

Animals↗

PubMed2003

Differential receptors create patterns diagnostic for ATP and GTP.

Herein we report the combination of a library of resin-bound sensors along with a multicomponent sensor array. This novel combinatorial array sensor system shows selectivity for nucleotide phosphates in solution. The design of the anchored receptor includes a 1,3,5-trisubstituted-2,4,6-triethylbenzene scaffold coupled with peptide libraries. Each chemosensor is placed into a micromachined cavity within a silicon wafer, and the optical changes observed by a charged-coupled device result in near-real-time digital analysis of solutions. A colorimetric displacement assay was performed, and time-dependent imaging studies of the selected sensing ensembles result in a differential responses upon addition of adenosine 5'-triphosphate (ATP), adenosine 5'-monophosphate (AMP), or guanosine 5'-triphosphate (GTP). An advantage to this approach is that it creates an array of sensors that gives a fingerprint response for each analyte. Principal component analysis indicates that the library of chemosensors can differentiate between ATP, GTP, and AMP. On the basis of factor loading values, individual sensors from the library were sequenced to elucidate their chemical composition.

Adenosine Triphosphate↗

PubMed1997

Molecular cloning of the cDNA coding for regucalcin and its mRNA expression in mouse liver: the expression is stimulated by calcium administration.

The molecular cloning of the cDNA coding for a Ca2+-binding protein regucalcin and its mRNA expression in mouse liver were investigated. The cDNA clone encoding a regucalcin was isolated from a mouse liver cDNA library and sequenced. Analysis of the sequence of the cloned cDNA showed that the cDNA encoded the complete amino acid sequence of the mouse regucalcin molecule; the cDNA had an open reading frame of 897 bp. Mouse regucalcin was composed of 299 amino acid residues, and its molecular weight was estimated to be 33,406 Da. The amino acid sequence of mouse regucalcin had 94% homology, as compared with that of rat regucalcin. Northern blot analysis with the mouse liver cDNA probe revealed that mouse regucalcin mRNA was mainly present in the liver but only slightly in the kidney with a size of 1.8 kb. Hepatic regucalcin mRNA level of male mouse was higher than that of female mouse. A single intraperitoneal administration of calcium chloride (5, 15, and 30 mg Ca2+/100 g body weight) to mice induced a remarkable increase in regucalcin mRNA in the liver; the increase in regucalcin mRNA levels at 30 min after calcium administration was dose-dependent. The present results demonstrate that regucalcin mRNA in mice is uniquely expressed in the liver, and that its expression is stimulated by calcium administration.

Amino Acid Sequence↗

PubMed1998

Molecular cloning of a zinc finger gene eZNF from a human inner ear cDNA library, and in situ expression pattern of its mouse homologue in mouse inner ear.

We have isolated and characterized the cDNA for eZNF, a zinc finger gene expressed in human inner ear, from a kinetically enriched human inner ear cDNA library. The sequence of full length cDNA was determined and its expression pattern characterized. A high degree of homology is shared between eZNF and rat transcription factor Kid-1. It belongs to the C2H2 class of zinc finger genes, contains a Kruppel-associated box (KRAB) domain near the N-terminus, and has consensus sites for phosphorylation. The gene is expressed in kidney and inner ear structures of mouse and human as determined by Northern blot analysis. In situ hybridization was used to demonstrate specific expression of the mouse eZNF homologue in epithelial layers of the saccule, semicircular canals, and the cochlea of newborn mice. The genomic clone corresponding to the cDNA was isolated and used for fluorescence in situ hybridization to localize it to human chromosome 5qter. The identification of genes expressed in human inner ear by representational difference analysis, their chromosomal location, and expression pattern of their homologues in developing mouse inner ear comprise a strategy that can potentially identify genes important in hearing and deafness.

Amino Acid Sequence↗

PubMed2003

Genomic structure of mouse PIR-A6, an activating member of the paired immunoglobulin-like receptor gene family.

The gene for one of the activating members of the paired Ig-like receptor family, Pira6, was isolated from a genomic library and sequenced. The first of 9 exons in the approximately 8.2 kb Pira6 gene encodes the 5' untranslated region, the translation initiation site, and approximately half of the signal sequence. The second exon encodes the rest of the signal sequence, exons 3-8 each encode a single Ig-like extracellular domain, and exon 9 encodes the transmembrane region, cytoplasmic tail and 3' UTR with four polyadenylation signals and six mRNA instability sequences. A soluble form of PIR-A6 may be generated by alternative splicing. The exonic sequences account for approximately 42% of the Pira6 gene and approximately 34% for the single inhibitory Pirb gene, thus defining Pira and Pirb as genes with relatively short intronic sequences. Extensive sequence homology was found between Pira6 and Pirb from approximately 2 kb upstream of the ATG initiation site to the beginning of intron 8. The Pir genes appear to be distributed in three regions of the proximal end of chromosome 7 based on the present data and an analysis of currently available mouse genomic sequence databases. One region contains a single Pir gene which is almost identical to Pira6, and the other two contain multiple Pir genes in opposite transcriptional orientations. Potential binding sites for hemopoiesis-specific and ubiquitous transcription factors were identified upstream of the Pira6 transcription start sites that reside within the initiator consensus sequence motif. These results provide important clues to the coordinate regulation observed for PIR-A and PIR-B expression during hematopoiesis.

Amino Acid Sequence↗

PubMed2003

Bst-2/HM1.24 is a raft-associated apical membrane protein with an unusual topology.

An expression screen of a rat cDNA library for sequences encoding Golgi-localized integral membrane proteins identified a protein with an apparent novel topology, i.e. with both an N-terminal transmembrane domain and a C-terminal glycosyl-phosphatidylinositol (GPI) anchor. Our data are consistent with this. Thus, the protein would have a topology that, in mammalian cells, is shared only by a minor, but pathologically important, topological isoform of the prion protein (PrP). The human orthologue of this protein has been described previously (BST-2 or HM1.24 antigen) as a cell surface molecule that appears to be involved in early pre-B-cell development and which is present at elevated levels at the surface of myeloma cells. We show that rat BST-2/HM1.24 has both a cell surface and an intracellular (juxtanuclear) location and is efficiently internalized from the cell surface. We also show that the cell surface pool of BST-2/HM1.24 is predominantly present in the apical plasma membrane of polarized cells. The fact that rat BST-2/HM1.24 apparently possesses a GPI anchor led us to speculate that it might exist in cholesterol-rich lipid microdomains (lipid rafts) at the plasma membrane. Data from several experiments are consistent with this localization. We present a model in which BST-2/HM1.24 serves to link adjacent lipid rafts within the plasma membrane.

Amino Acid Sequence↗

PubMedDate not supplied

A novel steroid thyroid hormone receptor-related gene inappropriately expressed in human hepatocellular carcinoma.

We have previously isolated from a human hepatocellular carcinoma a hepatitis B virus integration in a 147-base-pair cellular DNA fragment, similar to steroid- and c-erb-A/thyroid-hormone receptor genes. We have now cloned the corresponding complementary DNA from a human-liver cDNA library. Nucleotide sequence analysis revealed that the overall structure of the cellular gene, which we have named hap, is similar to that of the DNA-binding hormone receptors. That is, it displays two highly conserved regions identified as the putative DNA-binding and hormone-binding domains of the c-erb A/steroid receptors. Six out of seven hepatoma and hepatoma-derived cell-lines express a 2.5-kilobase (kb) hap messenger RNA species which is undetectable in normal adult and fetal livers but present in all non-hepatic tissues analysed. The data suggest that the hap gene product may be a novel ligand-responsive regulatory protein whose inappropriate expression in liver may relate to the hepatocellular carcinogenesis.

Amino Acid Sequence↗

PubMed1997

Differential expression of a cDNA clone in human liver versus hepatic cancer--highly homologous to aryl-dialkyl-phosphatase.

We applied the technique of mRNA differential display to normal liver tissue and hepatoma cell line Hep3B. One of the isolated cDNA clones was expressed in human normal liver tissue but not in the human hepatocarcinoma cell line. Northern Blot analysis confirmed that high level of mRNA was expressed in human normal liver tissue but the level was decreased in non-cancerous liver tissue from hepatoma patients. Low level or no expression was observed in human hepatoma tissue. One of these transcripts was about 1.8 kb in length. Southern Blot analysis showed that it was a single copy gene. We obtained a full length cDNA clone of 2,395 bp by screening human liver 5'-stretch plus cDNA library. Nucleotide sequence indicated that this clone was highly homologous to aryl-dialkyl-phosphatase and possessed two polymorphic sites. Aryl-dialkyl-phosphatase which has a prominent role in the metabolism of several toxic, synthetic compounds, may be potentially related to human hepatocarcinoma susceptibility. The biological significance of its differential expression in normal versus malignant tissue is discussed.

Amino Acid Sequence↗

PubMed1991

Molecular cloning, expression and characterization of ovine TNF alpha.

Tumour necrosis factor alpha (TNF alpha) is a cytokine with a wide range of effects on both lymphoid and non-lymphoid cell types. By hybridization with a human TNF alpha cDNA probe the corresponding ovine cDNA was isolated from a lipopolysaccharide (LPS) stimulated alveolar macrophage cDNA library. The sequence of the cDNA clone showed that ovine TNF alpha encodes a polypeptide of 234 amino acids that, based on analysis of human TNF alpha, is processed to a protein of 157 amino acids. The nucleotide and amino acid sequences showed a high degree of homology to the equivalent human and mouse molecules. In a mammalian COS cell expression system the ovine cDNA was found to encode a protein which was able to lyse actinomycin-D treated WEHI-164 cells and induce COS cells to produce and secrete interleukin 6 (IL-6). Further experiments demonstrated the importance of sequences within the 3' untranslated region of the cDNA in determining the level of expression of ovine TNF alpha. Northern blot analysis was used to analyse the kinetics of induction of ovine TNF alpha mRNA in alveolar macrophages stimulated with a variety of mitogens. Addition of LPS increased mRNA encoding TNF alpha at 1 h and 5 h but not 24 h post stimulation. In contrast, addition of phorbol myristic acid (PMA) led to increased TNF alpha mRNA at 5 h while the combination of PMA and ionomycin increased the level of specific mRNA detected at 1 h, 5 h and 24 h. From genomic analysis ovine TNF alpha appears to exist as a single copy.

Amino Acid Sequence↗

PubMed2025

Comprehensive discovery and functional characterization of the noncanonical proteome.

The systematic identification and functional characterization of noncanonical translation products, such as novel peptides, will facilitate the understanding of the human genome and provide new insights into cell biology. Here, we constructed a high-coverage peptide sequencing reference library with 11,668,944 open reading frames and employed an ultrafiltration tandem mass spectrometry assay to identify novel peptides. Through these methods, we discovered 8945 previously unannotated peptides from normal gastric tissues, gastric cancer tissues and cell lines, nearly half of which were derived from noncoding RNAs. Moreover, our CRISPR screening revealed that 1161 peptides are involved in tumor cell proliferation. The presence and physiological function of a subset of these peptides, selected based on screening scores, amino acid length, and various indicators, were verified through Flag-knockin and multiple other methods. To further characterize the potential regulatory mechanisms involved, we constructed a framework based on artificial intelligence structure prediction and peptide‒protein interaction network analysis for the top 100 candidates and revealed that these cancer-related peptides have diverse subcellular locations and participate in organelle-specific processes. Further investigation verified the interacting partners of pep1-nc-OLMALINC, pep5-nc-TRHDE-AS1, pep-nc-ZNF436-AS1 and pep2-nc-AC027045.3, and the functions of these peptides in mitochondrial complex assembly, energy metabolism, and cholesterol metabolism, respectively. We showed that pep5-nc-TRHDE-AS1 and pep2-nc-AC027045.3 had substantial impacts on tumor growth in xenograft models. Furthermore, the dysregulation of these four peptides is closely correlated with clinical prognosis. Taken together, our study provides a comprehensive characterization of the noncanonical proteome, and highlights critical roles of these previously unannotated peptides in cancer biology.

Humans↗

PubMed1998

Truncated c-Myb expression in the human leukemia cell line TK-6.

The c-MYB proto-oncogene encodes a transcription factor which plays an important role in hematopoiesis. We detected truncated c-MYB mRNA (2.0 kb) and c-Myb protein (55 kDa) in the TK-6 cell line, which was established from a patient with chronic myelogenous leukemia in T cell blast crisis. Mutated c-MYB cDNA clone (WTK-1) was isolated from a TK-6 cell cDNA library and sequenced in its entirety. Compared with the wild-type human c-MYB sequence, the WTK-1 sequence diverged at the 3' ends of exons 9. A termination codon was present as the second codon downstream from the point of divergence and was followed by a previously unknown rearranged sequence. The conceptual protein encoded by WTK-1 (Myb(TK-6)) comprises 402 amino acids and lacks the negative regulatory domain of the normal c-Myb, reminiscent of the activated form of Myb protein. Luciferase reporter assay in NIH3T3 cells showed that the expression vector encoding Myb(TK-6) stimulated Myb-regulated mim-1 promoter more effectively than that encoding wild-type human c-Myb, suggesting that Myb(TK-6) is functional as a transcription factor, and thus as a potential transforming protein. Southern blot and mutant allele-specific polymerase chain reaction analyses showed that the same rearrangement of the c-MYB gene in TK-6 was present in late, but not in early, specimens obtained from the patient, indicating that this mutation had been acquired during disease progression.

Adult↗

PubMed1998

A variant transcript encoding an isoform of the human protein tyrosine kinase EPHB2 is generated by alternative splicing and alternative use of polyadenylation signals.

We previously isolated and characterized cDNA clones of DRT (EPHB2), encoding a receptor protein-tyrosine kinase of the EPH family. Northern blot analysis showed that EPHB2 transcripts are expressed in three sizes of approximately 4, 5, and 11 kb, suggesting that these transcripts are generated by alternative splicing and/or alternative use of polyadenylation sites. To explore this possibility, we isolated additional EPHB2 cDNA clones, including clone 5K-1, by re-screening the human fetal brain cDNA library. Nucleotide sequence analysis of clone 5K-1 revealed that it represents a variant transcript of EPHB2 (EPHB2v). Relative to the EPHB2 cDNA sequence previously reported, clone 5K-1 has two coding region deletions of 3 and 93 nucleotides. Nucleotide sequence analyses of EPHB2 genomic DNA fragments corresponding to these deletions suggest that the EPHB2v transcript is generated by alternative splicing. The 3' end of clone 5K-1 contains a polyadenosine stretch preceded by a potential polyadenylation signal, which is not used to generate the EPHB2 transcript. Taken together, these data indicate that EPHB2v is generated by both alternative splicing and alternative use of polyadenylation sites. The EPHB2v protein lacks one arginine residue that resides immediately following the EPHB2 transmembrane domain. In contrast, as a result of the frame shift caused by the 93 nucleotide deletion, the C-terminus of the EPHB2v protein is longer by 70 amino acids than that of EPHB2. We also show that the human neuroblastoma cell line SY5Y and NTera-2N neurons express high levels of EPHB2 and lower levels of EPHB2v. These structural variations found between the EPHB2 and EPHB2v proteins may reflect functional heterogeneity of EPHB2.

Alternative Splicing↗