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1.
Science ; 208(4439): 57-9, 1980 Apr 04.
Artículo en Inglés | MEDLINE | ID: mdl-6927840

RESUMEN

Recombinant bacterial plasmids that contain DNA complementary to human preproinsulin messenger RNA have been constructed. One clone contains the entire preproinsulin coding region, as well as the 3' untranslated region of the messenger RNA and eight nucleotides of the 5' untranslated region. Additional sequence information for the 5' untranslated region was obtained with the use of insulinoma messenger RNA in conjunction with specific primers from the cloned DNA for enzymatic chain termination sequence analysis. The results confirm the amino acid sequence of human proinsulin previously determined, and predict the amino acid sequence of the human preproinsulin signal peptide.


Asunto(s)
Nucleótidos/genética , Proinsulina/genética , Precursores de Proteínas/genética , ARN Mensajero/genética , Secuencia de Aminoácidos , Secuencia de Bases , Clonación Molecular , ADN Recombinante , Humanos , Insulina , Hibridación de Ácido Nucleico
2.
Science ; 209(4456): 612-5, 1980 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-6248962

RESUMEN

Four recombinant lambda phages containing nucleotide sequences complementary to a cloned human preproinsulin DNA probe have been isolated from human DNA. Restriction analyses in conjunction with Southern hybridizations reveal two types of gene sequences. One isolate of each type was subjected to complete nucleotide sequence determination. The sequences contain the entire preproinsulin messenger RNA region, two intervening sequence. 260 nucleotides upstream from the messenger RNA capping site, and 35 nucleotides beyond the polyadenylate attachment site. Our results strongly suggest that these two gene types are allelic variants of a single insulin gene.


Asunto(s)
ADN , Genes , Variación Genética , Insulina/biosíntesis , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Clonación Molecular , Enzimas de Restricción del ADN , ADN Recombinante/metabolismo , Código Genético , Humanos , Hibridación de Ácido Nucleico , Proinsulina/biosíntesis , Ratas , Especificidad de la Especie
3.
Cancer Res ; 52(22): 6139-43, 1992 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-1384954

RESUMEN

The protooncogene c-kit encodes a tyrosine kinase with a molecular weight of 145,000, highly related to the platelet derived growth factor/colony stimulating factor receptors. Mutations of the murine gene result in impairment of hematopoiesis, gametogenesis, and of the melanocyte cell lineage. In order to elucidate c-kit functions in development and oncogenesis we have analyzed immunohistochemically its expression in human normal and transformed nonlymphoid tissues. The receptor has been detected in spermatogonia, melanocytes, and unexpectedly, in astrocytes, renal tubules, parotid cells, thyrocytes, and breast epithelium. While the gene product is expressed in seminoma, lung tumors, and melanoma of low invasiveness, no detectable levels have been detected in thyroid and breast carcinomas, astrocytomas, and invasive melanomas. In breast tumors these findings were confirmed by paired, Northern blot analysis of RNA preparations from normal and transformed tissue. The present results demonstrate that the c-kit receptor plays a role in the development of a larger spectrum of cell lineages. Furthermore, on the basis of the transformation associated changes, we speculate that, while in some cell types, c-kit expression positively regulates mitogenesis and is selected for in neoplastic transformation, in other tissues the c-kit pathway is involved in morphogenesis and differentiation and is, therefore, negatively selected in the course of tumor progression.


Asunto(s)
Transformación Celular Neoplásica/genética , Expresión Génica/genética , Neoplasias/genética , Proteínas Proto-Oncogénicas/genética , Adulto , Anticuerpos Monoclonales , Astrocitoma/química , Astrocitoma/genética , Northern Blotting , Neoplasias de la Mama/química , Neoplasias de la Mama/genética , Disgerminoma/química , Disgerminoma/genética , Epitelio/química , Epitelio/fisiología , Humanos , Inmunohistoquímica , Neoplasias Pulmonares/química , Neoplasias Pulmonares/genética , Melanoma/química , Melanoma/genética , Neoplasias/química , Proteínas Proto-Oncogénicas/análisis , Proteínas Proto-Oncogénicas c-kit , Neoplasias de la Tiroides/química , Neoplasias de la Tiroides/genética
4.
Oncogene ; 13(10): 2275-9, 1996 Nov 21.
Artículo en Inglés | MEDLINE | ID: mdl-8950995

RESUMEN

Using a polymerase chain reaction (PCR) amplification strategy, we identified a novel protein tyrosine phosphatase (PTPase) designated Brain Derived Phosphatase (BDP1). The full length sequence encoded an open reading frame of 459 amino acids with no transmembrane domain and had a calculated molecular weight of 50 kDa. The predicted amino acid sequence contained a PEST motif and accordingly, BDP1 shared the greatest homology with members of the PTP-PEST family. When transiently expressed in 293 cells BDP1 hydrolyzed p-Nitrophenylphosphate, confirming it as a functional protein tyrosine phosphatase. Northern blot analysis indicated that BDP1 was expressed not only in brain, but also in colon and several different tumor-derived cell lines. Furthermore, BDP1 was found to differentially dephosphorylate autophosphorylated tyrosine kinases which are known to be overexpressed in tumor tissues.


Asunto(s)
Proteínas Tirosina Fosfatasas/genética , Secuencia de Aminoácidos , Secuencia de Bases , Encéfalo/enzimología , Humanos , Datos de Secuencia Molecular , Peso Molecular , Sistemas de Lectura Abierta/genética , Reacción en Cadena de la Polimerasa/métodos , Proteína Tirosina Fosfatasa no Receptora Tipo 12 , Proteínas Tirosina Fosfatasas/química , Proteínas Tirosina Fosfatasas/aislamiento & purificación , Células Tumorales Cultivadas/enzimología
5.
Oncogene ; 11(10): 2179-84, 1995 Nov 16.
Artículo en Inglés | MEDLINE | ID: mdl-7478540

RESUMEN

Complementary DNA (cDNA) encoding a novel member of the receptor tyrosine kinase (RTK) family has been isolated from colon carcinoma tissue. Colon carcinoma kinase 4 (CCK-4) mRNA is highly expressed in human lung tissue and at lower levels in the thyroid gland and ovary. While no mRNA was found in human adult colon tissues, expression varied remarkably in colon carcinoma-derived cell lines. CCK-4 cDNA encodes a chicken KLG-related, 1071 amino acid-long transmembrane glycoprotein containing several genetic alterations within the RTK consensus sequences. These define CCK-4 as a catalytically inactive member of the RTK family of proteins and, in analogy to HER3, suggest a potentially tumor-characteristic role as a signal amplifier or modulator for an as yet unidentified kinase-competent partner.


Asunto(s)
Moléculas de Adhesión Celular , Neoplasias del Colon/enzimología , Proteínas de Neoplasias/genética , Proteínas Tirosina Quinasas Receptoras/genética , Adulto , Secuencia de Aminoácidos , Secuencia de Bases , Neoplasias del Colon/genética , ADN de Neoplasias/análisis , ADN de Neoplasias/genética , ADN de Cadena Simple/análisis , ADN de Cadena Simple/genética , Expresión Génica , Humanos , Datos de Secuencia Molecular , Proteínas de Neoplasias/análisis , Reacción en Cadena de la Polimerasa , ARN Mensajero/análisis , ARN Mensajero/genética , Proteínas Tirosina Quinasas Receptoras/análisis , Proteínas Tirosina Quinasas Receptoras/clasificación , Transfección
6.
Mech Dev ; 55(2): 171-84, 1996 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-8861097

RESUMEN

Members of the Polycomb group (Pc-G) of genes encode transcriptional regulators that control the expression of key developmental effector genes in Drosophila melanogaster. Although multiple Pc-G genes have been identified and characterized in Drosophila, information about these important regulatory proteins in vertebrates, including their precise expression patterns, has remained scarce. We report here the cloning of Enx-1, a novel vertebrate Pc-G gene, which encodes the murine homolog of the Drosophila Enhancer of zeste (E(z)) gene. Drosophila E(z) controls the expression of several homeobox genes as well as some segmentation genes and its disruption causes multiple phenotypes in Drosophila development. Analysis of the primary structure of murine Enx-1 reveals the conservation of several regions, including the previously described SET domain and a newly defined CXC domain. In addition, we find the SET domain to be conserved in evolutionarily distant species ranging from vertebrates to plants and fungi. The expression pattern analysis of Enx-1 reveals ubiquitous expression throughout early embryogenesis, while in later embryonic development Enx-1 expression becomes restricted to specific sites within the central and peripheral nervous system and to the major sites of fetal hematopoiesis. In adult stages we also find Enx-1 expression to be restricted to specific tissues, including spleen, testis and placenta.


Asunto(s)
Proteínas de Drosophila , Regulación del Desarrollo de la Expresión Génica , Proteínas de Insectos/genética , Proteínas Represoras/genética , Factores de Transcripción/genética , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Clonación Molecular , Secuencia Conservada , Drosophila/embriología , Drosophila/genética , Ratones , Ratones Endogámicos BALB C , Datos de Secuencia Molecular , Complejo Represivo Polycomb 1 , Proteínas del Grupo Polycomb , Alineación de Secuencia
10.
Proc Natl Acad Sci U S A ; 81(2): 380-4, 1984 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-6582494

RESUMEN

We have synthesized two oligodeoxyribonucleotide mixtures that contain sequences complementary to different parts of the hypothetical mRNA sequence of xenopsin, a biologically active octapeptide found in skin extracts from Xenopus laevis. The two primer pools were independently used to initiate reverse transcription on skin poly(A)+ RNA and the resulting cDNAs were then used to screen in parallel a cDNA library prepared from skin poly(A)+ RNA. One of the clones that hybridized with both probes was subjected to sequence analysis. It contains a nearly full-length DNA copy of a mRNA of approximately equal to 490 nucleotides that encodes a xenopsin precursor protein. The deduced precursor is 80 amino acids long, exhibits a putative signal sequence at the NH2 terminus, and contains the biologically active peptide at the COOH terminus. The region corresponding to the NH2-terminal portion of the xenopsin precursor shows a striking nucleotide and amino acid sequence homology with the precursor of PYLa, another recently described peptide from Xenopus skin.


Asunto(s)
Oligopéptidos/genética , Proteínas de Xenopus , Xenopus laevis/fisiología , Secuencia de Aminoácidos , Animales , Clonación Molecular , ADN/genética , Neurotensina/genética , Péptidos , Precursores de Proteínas/genética , ARN Mensajero/genética
11.
Proc Natl Acad Sci U S A ; 77(5): 2546-50, 1980 May.
Artículo en Inglés | MEDLINE | ID: mdl-6994099

RESUMEN

The complete nucleotide sequence of the actin gene from Saccharomyces cerevisiae has been determined. The coding region is interrupted by a 304-base-pair intervening sequence that is located within the triplet coding for amino acid 4. DNA sequences of the intron-exon junctions are similar to those found in higher eukaryotes and can be aligned such that the intron starts with the dinucleotide 5'-G-T-3' and ends with 5'-A-G-3'. Regions fo homology within the sequences upstream from the initiation codon and those following the termination codon have been detected between the yeast iso-1-cytochrome c gene and the actin gene. As deduced from the nucleotide sequence, yeast actin has 374 amino acid residues. Its primary structure, especially the NH2-terminal third of the protein, is highly conserved during evolution.


Asunto(s)
Actinas/genética , Genes , Saccharomyces cerevisiae/genética , Aminoácidos/análisis , Secuencia de Bases , Codón , ADN Recombinante , Precursores de Ácido Nucleico/genética , ARN Mensajero/genética
12.
Eur J Biochem ; 179(2): 281-5, 1989 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-2465151

RESUMEN

From genomic libraries of Xenopus laevis, parts of the genes coding for the precursors of the skin peptides GLa (peptide with amino-terminal glycine and carboxy-terminal leucinamide), xenopsin and levitide have been isolated and sequenced. The gene for prepropeptide GLa comprises four exons, separated by relatively small introns. The gene for preproxenopsin is composed of five exons, of which all but the last one have been analyzed. This is a large gene encompassing at least 25,000 base pairs. In addition, two exons of the gene for preprolevitide have been isolated. A comparison of these genes reveals the presence of a homologous exon. This exon contains 161 bp, starts one base pair prior to the initiation codon and encodes a signal peptide and part of a pro region with processing sites. In addition, the two genes for preprocaerulein analyzed previously [Vlasak et al. (1987) Eur. J. Biochem. 169, 53-58] also contain a similar exon. This demonstrates the existence of a homologous export exon in genes encoding the precursors of different skin peptides.


Asunto(s)
Péptidos Catiónicos Antimicrobianos , Péptidos/genética , Señales de Clasificación de Proteína/genética , Piel/análisis , Proteínas de Xenopus , Animales , Secuencia de Bases , Ceruletida/genética , Clonación Molecular , ADN/análisis , Exones , Genes , Código Genético , Intrones , Datos de Secuencia Molecular , Oligopéptidos/genética , Péptidos/análisis , ARN/análisis , Homología de Secuencia de Ácido Nucleico , Xenopus laevis
13.
Biochemistry ; 15(12): 2541-6, 1976 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-779826

RESUMEN

The studies presented were undertaken to clarify the unsettled question whether the synthesis of histones with a N-acetylserine residue at the amino terminal end is initiated with methionine. Histones were synthesized in vitro in a rabbit reticulocyte lysate, primed with a mRNA preparation from ascites cells. Initiation of polypeptide synthesis was investigated by using N-formyl[35S]met-tRNAfMet from yeast to label the N-termini. N-Formylmethionine was incorporated into histones H1 and H4 whose N-terminal amino acid is alpha-N-acetylserine. By comparison of tryptic peptides derived from these two histones labeled either with methionine or formylmethionine and from Edman degradation it is shown that N-terminal acetylated histones are initiated with methionine, as is the case for other eukaryotic and bacterial proteins.


Asunto(s)
Histonas/biosíntesis , Metionina/metabolismo , Biosíntesis de Proteínas , Secuencia de Aminoácidos , Animales , Escherichia coli/metabolismo , Ratones , Neoplasias Experimentales , Fragmentos de Péptidos/análisis , ARN Mensajero/metabolismo
14.
J Biol Chem ; 257(16): 9438-43, 1982 Aug 25.
Artículo en Inglés | MEDLINE | ID: mdl-7107576

RESUMEN

We have determined the nucleotide sequence of the gene that codes for an H1 histone associated with euchromatin in the sea urchin Strongylocentrotus purpuratus. The gene codes for a protein of 205 amino acids. The nucleotide sequence of this gene is homologous to the sequence of H1 mRNA that is expressed during early embryonic development. We have compared the nucleotide and protein coding sequences of this H1 gene to those of the early H1 histone gene of the sea urchin Psammechinus miliaris. There is considerable drift by nucleotide substitution between the two genes randomly distributed across the mRNA coding region. Despite this divergence of nucleotide sequence, there are local constraints on amino acid substitutions throughout the molecule and especially in its central region. We have also compared the amino acid sequence in this central hydrophobic region of the euchromatic S. purpuratus H1 histone to the same region in H1 and H5 histones associated with heterochromatin. We show that certain amino acids are conserved and aligned in frameworks in all the sequenced H1 proteins.


Asunto(s)
Cromatina/metabolismo , ADN , Histonas/genética , Erizos de Mar/embriología , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Histonas/metabolismo , ARN Mensajero
15.
Cell ; 15(3): 1033-44, 1978 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-728984

RESUMEN

The DNA sequence of two cloned segments of the histone gene repeat unit of the sea urchin S. purpuratus has been determined. One sequence contains the contiguous H2B and H3 genes and their interdigitated spacer regions; the other comprises the H2A gene and flanking spacer sequences. Analysis of the coding regions reveals a methionine residue within the H2A protein. H2A, which generally lacks this amino acid, contains methionine only in a protein variant which is synthesized in early sea urchin embryogenesis. We thus conclude that the cloned DNA represents a set of genes which is active early in development. Codon selection is markedly skewed and similar for each of the three genes. The DNA sequences are co-linear with known histone protein sequences and-unlike several other eucaryotic genes-do not show any insertions in the coding regions. The spacer regions are relatively AT-rich although GC cluster are scattered throughout. Several short stretches of homology are found in regions both upstream and downstream from the protein coding segments. The conservation of these sequences and their location at analogous sites suggest that they are involved in gene transcription or in mRNA translation. No tandem or dispersed repeats were found, with the exception of the remarkable sequence having the structure located in the spacer between the H2A and H1 genes.


Asunto(s)
ADN/genética , Histonas/genética , Erizos de Mar/genética , Animales , Secuencia de Bases , Mapeo Cromosómico , Codón , Ligamiento Genético , Terminación de la Cadena Péptídica Traduccional , Biosíntesis de Proteínas , ARN Mensajero/genética
16.
Proc Natl Acad Sci U S A ; 77(3): 1265-9, 1980 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-6154927

RESUMEN

We have determined the sequence of the untranslated leader nucleotides of all five histone mRNAs from Strongylocentrotus purpuratus by the dideoxy chain termination method. Total polysomal RNA from sea urchin embryos was used as a substrate for cDNA synthesis primed by specific DNA restriction fragments. Each of the primers was derived from the 5'-terminal part of the coding region for a different histone protein. The five histone mRNA leader sequences are different in length and primary structure. The 5' termini of all five histone mRNAs coincide with the unique heptanucleotide Py-Py-A-T-T-C-Pu in genomic DNA. This sequence, which defines the start of the individual histone mRNAs, is preceded by the A+T-rich octanucleotide identified in front of all eukaryotic structural genes where sequences have been determined to date.


Asunto(s)
Genes , Histonas/genética , ARN Mensajero/genética , Erizos de Mar/genética , Animales , Secuencia de Bases , Codón , ADN Polimerasa Dirigida por ARN/metabolismo , Transcripción Genética
17.
Mol Biol Rep ; 9(1-2): 33-8, 1983 May.
Artículo en Inglés | MEDLINE | ID: mdl-6888377

RESUMEN

A cDNA library prepared from mRNA of Xenopus laevis embryos was screened with a genomic DNA fragment containing various transcribed repetitive sequence elements. Comparison of the nucleotide sequence of two isolated cDNAs and their genomic relatives allows one to define two transcribed repetitive sequence elements. One of them belongs to a highly reiterated family and consists of a tandem array of homologous subunits of 77-80 bp. The other is reiterated approximately 2200 times, has a size of 260 bp and displays a conserved region of 135 bp. The data are consistent with the presence of repetitive sequence transcripts in the 3' part of mRNA molecules.


Asunto(s)
Secuencias Repetitivas de Ácidos Nucleicos , Xenopus laevis/crecimiento & desarrollo , Animales , Secuencia de Bases , Clonación Molecular , Peso Molecular , ARN Mensajero/genética , Transcripción Genética , Xenopus laevis/embriología , Xenopus laevis/genética
18.
Int J Cancer ; 52(5): 713-7, 1992 Nov 11.
Artículo en Inglés | MEDLINE | ID: mdl-1385336

RESUMEN

The proto-oncogene c-kit encodes a tyrosine kinase receptor related to the PDGF/CSF-1 receptors. Mutations of this gene result in impairment of hematopoiesis, melanogenesis and gametogenesis. Using monoclonal antibodies to the c-kit gene product, we have analyzed its expression in normal and transformed human tissues. Unexpectedly, the receptor was found to be expressed in normal mammary epithelium. While in benign breast lesions, the c-kit gene product was detected at variable levels in 82% of the instances, in primary tumors, no product could be identified in 87% of the cases. This phenotype is maintained in metastatic foci. These findings were confirmed by paired Northern blot analysis of RNA preparations from normal and tumor tissues. These results demonstrate that the c-kit receptor may also be involved in the growth control of mammary epithelium and that this function may be impaired following malignant transformation and de-differentiation.


Asunto(s)
Neoplasias de la Mama/genética , Mama/fisiología , Proteínas Proto-Oncogénicas/metabolismo , Northern Blotting , Catepsinas/metabolismo , Epitelio/fisiología , Expresión Génica , Humanos , Metástasis de la Neoplasia , Pronóstico , Proto-Oncogenes Mas , Proteínas Proto-Oncogénicas/genética , Proteínas Proto-Oncogénicas c-kit , ARN Mensajero/genética , ARN Neoplásico/genética , Receptores de Esteroides/metabolismo
19.
Cell ; 9(4 Pt 1): 495-502, 1976 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-795548

RESUMEN

A 2000 base pair (bp) DNA fragment can be excised from sea urchin (S. purpuratus) histone gene repeat units with restriction endonuclease Eco R1. This DNA, which has been cloned in a bacterial plasmid, is known to encompass two of the five histone genes. The fragment has a single endonuclease Hind III cleavage site in one of the genes and a Hae III cleavage site in the other gene. We now report the nucleotide sequences of 62 bp adjacent to the Hind III site and 42 bp adjacent to the Hae III cleavage site. The results identify the cloned DNA as histone genes, show that it codes for histone proteins H2A and H3, and locate and orient H2A and H3 genes with respect to restriction endonuclease sites in the repeat unit.


Asunto(s)
ADN/análisis , Genes , Histonas/biosíntesis , Animales , Secuencia de Bases , Enzimas de Restricción del ADN , ADN Recombinante , Escherichia coli , Datos de Secuencia Molecular , Plásmidos , Erizos de Mar
20.
Nature ; 386(6621): 181-6, 1997 Mar 13.
Artículo en Inglés | MEDLINE | ID: mdl-9062191

RESUMEN

Phosphotyrosine phosphatases are critical negative or positive regulators in the intracellular signalling pathways that result in growth-factor-specific cell responses such as mitosis, differentiation, migration, survival, transformation or death. The SH2-domain-containing phosphotyrosine phosphatase SHP-2 is a positive signal transducer for several receptor tyrosine kinases (RTKs) and cytokine receptors. To investigate its mechanism of action we purified a tyrosine-phosphorylated glycoprotein which in different cell types associates tightly with SHP-2 and appears to serve as its substrate. Peptide sequencing in conjunction with complementary DNA cloning revealed a new gene family of at least fifteen members designated signal-regulatory proteins (SIRPs). They consist of two subtypes distinguished by the presence or absence of a cytoplasmic SHP-2-binding domain. The transmembrane polypeptide SIRP alpha1 is a substrate of activated RTKs and in its tyrosine-phosphorylated form binds SHP-2 through SH2 interactions and acts as its substrate. It also binds SHP-1 and Grb2 in vitro and has negative regulatory effects on cellular responses induced by growth factors, oncogenes or insulin. Our findings indicate that proteins belonging to the SIRP family generally regulate signals defining different physiological and pathological processes.


Asunto(s)
Proteínas de la Membrana/metabolismo , Proteínas Tirosina Fosfatasas/metabolismo , Proteínas Tirosina Quinasas Receptoras/metabolismo , Transducción de Señal , Secuencia de Aminoácidos , Animales , División Celular/efectos de los fármacos , Células Cultivadas , Factor de Crecimiento Epidérmico/farmacología , Humanos , Insulina/farmacología , Proteínas de la Membrana/genética , Datos de Secuencia Molecular , Mutación Puntual , Ratas , Transfección , Dominios Homologos src
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