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B Wieringa

Publications and source records attributed to B Wieringa.

At least 163 records · Page 9Linked to original sources
PubMed1987

An interstitial duplication of the X chromosome in a male allows physical fine mapping of probes from the Xq13-q22 region.

An insertional translocation into the proximal long arm of the X chromosome in a boy showing muscular hypotony, growth retardation, psychomotor retardation, cryptorchidism, and Pelizaeus-Merzbacher disease (PMD) was identified as a duplication of the Xq21-q22 segment by employing DNA probes. With densitometric scanning for quantitation of hybridization signals, 15 Xq probes were assigned to the duplicated region. Analysis of the duplication allowed us to dissect the X-Y homologous region physically at Xq21 and to refine the assignments of the loci for DXYS5, DXYS12, DXYS13, DXS94, DXS95, DXS96, DXS111, and DXS211. Furthermore, we demonstrated the presence of two different DXYS13 and DXS17 alleles in genomic DNA of our patient, suggesting that the duplication resulted from a meiotic recombination event involving the two maternal X chromosomes.

Abnormalities, Multiple↗
PubMed1987

Cloning and nucleotide sequence of rat ornithine decarboxylase cDNA.

The enzyme ornithine decarboxylase (ODC; EC 4.1.1.17) catalyses the first and rate-limiting step in polyamine biosynthesis. Its activity is markedly increased in rapidly growing or regenerating tissue and is subject to regulation by a variety of trophic and mitogenic stimuli. ODC is therefore believed to play an essential role in the onset of cellular proliferation. In a molecular-biological approach to investigate ODC regulation upon induction by tumor promoters in rat liver we isolated an almost full-length rat ODC cDNA clone of 2.4 kb (designated pODC.E10) from a cDNA library of testosterone-induced rat kidney poly(A)+ RNA. Characterization by restriction-endonuclease mapping and sequence analysis showed strong homology to mouse ODC cDNA sequences previously published [Gupta and Coffino, J. Biol. Chem. 260 (1985) 2941-2944; Kahana and Nathans, Proc. Natl. Acad. Sci. USA 82 (1985) 1673-1677; Hickok et al., Proc. Natl. Acad. Sci. USA 83 (1986) 594-598]. This homology is most pronounced in the 461-aa-spanning coding region, amounting to 94% and 97% at the DNA and protein levels, respectively. In the 423-nt 5' leader the rat-mouse homology (approx. 75%) is most pronounced in a region of about 175 nt directly upstream from the translational start site. The leader sequence also contains a perfect inverted repeat of 54 nt and ten additional upstream ATG triplets, which are all followed by nonsense codons before the initiating ATG. In the 633-nt 3' trailer region of pODC.E10 an additional polyadenylation signal is observed more than 300 nt upstream from the 3' end. Rat-mouse homology is about 80% up to this first polyadenylation signal and is considerably less thereafter. The presence of two alternate polyadenylation sites most likely accounts for the 3' size heterogeneity observed in the two ODC mRNAs of 2.1 and 2.6 kb, respectively. In rat liver both mRNAs are coordinately induced by different tumor promoters. Finally, Southern blot analysis of normal rat liver and rat hepatoma DNA revealed that rat ODC, as in other rodents, belongs to a multigene family.

Amino Acid Sequence↗
PubMed1987

Structure and expression of the human creatine kinase B gene.

Various cDNAs for creatine kinase type B (CK-B) were isolated from human cDNA libraries using a 26-oligonucleotide guess-mer probe. One of the cDNAs appeared to be almost full-length and contained an open reading frame coding for the 381 amino acid residues of the human CK-B polypeptide. The nucleotide sequences of the translated region as well as the primary protein structure show a high degree of homology with known CK-B and CK-M sequences of other vertebrates. The level of CK-B RNA as a measure of CK-B gene activity was determined in various human tissues and cultured cells. Our results confirm that CK-B is expressed in a tissue-specific manner and give support to the previously proposed relation between CK-B gene activity and cell proliferation. Screening of genomic DNA with various cDNA regions as probes revealed that there is only one CK-B gene per haploid genome. Gene cloning and sequencing indicated that CK-B is coded for by a relatively small gene of 3.2 kb in size, which is partially overlapped by an HTF island (A. P. Bird (1986) Nature (London) 321, 557-558) with an extremely high G + C content at its 5' end.

Amino Acid Sequence↗
PubMed1987

Deletion of the DXS165 locus in patients with classical choroideremia.

Using various probes from the Xq21 region which is known to carry the choroideremia (tapetochoroideal dystrophy, TCD) locus, we have screened the DNAs from eight unrelated male choroidermia patients for microdeletions. In two of these patients, but not in any of 45 males tested as controls, lack of hybridization signals with probe plbD5 suggested a deletion encompassing the DXS165 locus and (part of) the TCD gene. Absence of additional clinical features in these patients and the fact that two closely linked, and probably flanking, TCD markers (DXYS1 and DXS72) are not deleted may indicate that the physical distance between the DXS165 locus and the TCD gene is small.

Choroid↗
PubMed1987

Localization of PEPD to the long arm of chromosome 19.

A panel of human-rodent somatic cell hybrids containing different regions of chromosome 19 has been used to obtain a regional localization for peptidase D. The results assign PEPD to the long arm of chromosome 19, in the region cen-q13.2

Animals↗
PubMed1986

A physical map of 4 million bp around the Duchenne muscular dystrophy gene on the human X-chromosome.

Employing pulsed field gradient electrophoresis, we constructed a 4.5 million bp (Mb) Sfil restriction map of the human X-chromosomal region p21, harboring genes for Duchenne (DMD) and Becker Muscular Dystrophy. In a DMD patient with additional chronic granulomatosis and retinitis pigmentosa, the proximal 3.5 Mb is deleted. Another DMD patient, with additional glycerol kinase deficiency and adrenal hypoplasia, lacks at least 3.3 Mb in the middle region, including marker C7 but not B24, placing C7 closer to DMD. Another DMD patient has a partial pERT-87 deletion of minimally 140 kb. Truncated Sfil fragments in a female X:21 translocation patient place the junction probe XJ1.1 115 kb from the distal end of the normal fragment. Probe pERT-84 maps to the same fragment, within 750 kb of XJ1.1.

Chromosome Aberrations↗
PubMed1986

Isolation of a random cosmid clone, cX5, which defines a new polymorphic locus DXS148 near the locus for Duchenne muscular dystrophy.

We have isolated a random cosmid cX5 (DXS148), which maps into a small Xp21 deletion associated with Duchenne muscular dystrophy (DMD), chronic granulomatous disease (CGD), retinitis pigmentosa (RP) and McLeod syndrome, cX5 maps proximally outside several other deletions associated with DMD, glycerol kinase deficiency (GK) and adrenal hypoplasia (AHC). The following order of loci is proposed: centromere-OTC-cX5 (DXS148)-754 (DXS84)-PERT87 (DXS164)/DMD-telomere. A subclone cX5.7, isolated from this cosmid, identifies an MspI RFLP, with a minor allele frequency of 35%. This probe forms an important adjunct to the existing RFLPs for family studies in Duchenne muscular dystrophy.

Chromosome Deletion↗
PubMed1986

Demonstration of X chromatin in drumstick-like nuclear appendages of leukocytes by in situ hybridization on blood smears.

An X chromosome specific nucleic acid probe was used to study the positions of the X chromosomes in leukocyte nuclei by in situ hybridization to smears of peripheral blood. This autoradiographic approach allowed the first direct demonstration of the presence of X chromosomal material in the drumstick-like structures of female polymorphonuclear leukocytes.

Cell Nucleus↗
PubMed1986

Submicroscopic interstitial deletion of the X chromosome explains a complex genetic syndrome dominated by Norrie disease.

Norrie disease (ND), an X-linked recessive disorder, is characterized by congenital blindness followed by bulbar atrophy. We have examined a three-generation family in which ND is part of a complex X-linked syndrome with severe mental retardation, hypogonadism, growth disturbances, and increased susceptibility to infections as additional features. This syndrome is apparently due to an interstitial deletion, as evidenced by the failure of the L1.28 DNA probe (DXS7 locus, Xp11.3) to detect complementary DNA sequences on the defective X chromosome of an affected male and of several obligatory heterozygotes. Attempts to further define this deletion with other DNA probes from the proximal short arm of the X chromosome or by prometaphase chromosome analysis were unsuccessful.

Adolescent↗
PubMed1986

Toward early diagnosis of myotonic dystrophy: construction and characterization of a somatic cell hybrid with a single human der(19) chromosome.

We have constructed a somatic cell hybrid line, designated 908K1, with a single human der(19) chromosome on a Chinese hamster background by employing conventional as well as microcell-mediated cell fusion techniques. The der(19) chromosome comprises the 19p13.1----q13.2 segment, as well as the distal (Xq24----qter) portion of the X chromosome long arm, and is stably retained by HAT selection. Extensive characterization of this hybrid line and comparison with other somatic cell hybrids has enabled us to regionally assign PGK2 to the distal short arm of chromosome 19 and to narrow down the assignments of CYP1, TGFB, and ERCC1 on 19q. Moreover, a cosmid library has been constructed from this microcell hybrid. By screening this library, as well as a chromosome 19-enriched library obtained elsewhere, 14 single-copy probes have been isolated that map on the 19p13.1----q13.2 segment, and 5 probes were assigned to the distal Xq. It is anticipated that these probes will be useful for the diagnosis of myotonic dystrophy and fra(X) mental retardation.

Animals↗
PubMed1984

A minimal intron length but no specific internal sequence is required for splicing the large rabbit beta-globin intron.

We constructed rabbit beta-globin genes with deletions in the large intron, extending from the midpoint toward the 5' or 3' splice sites. Analysis of transcripts in transformed HeLa cells showed that six 5' proximal intron nucleotides allowed normal splicing. Correct splicing at the 3' splice site required 12 or more 3' proximal intron nucleotides; optimal efficiency required 24 nucleotides. Remarkably, a mini-intron comprising six 5' and 24 3' intron nucleotides gave no correctly spliced transcripts; extending the miniintron with polyoma or pBR322 fragments to 80 or more nucleotides restored normal splicing. Thus other than in yeast nuclear genes, no specific internal intron sequences appear to be needed but a minimal intron length is important.

Animals↗
PubMed1983

Unusual splice sites revealed by mutagenic inactivation of an authentic splice site of the rabbit beta-globin gene.

Only one of six point mutations of the sequence around one end of the larger of the introns of the rabbit beta-globin gene seriously affects the normal removal of the intron and splicing of the gene. That mutation converts a GT sequence, invariably found at the 5' end of introns, into an AT, which is no longer recognized as a signal for intron removal. Instead, three normally unused (cryptic) sites are used, leading to aberrant gene transcripts. One of the cryptic sites is an exception to the invariable GT sequence.

Animals↗
PubMed1983

Evidence against a scanning model of RNA splicing.

A cloned rabbit beta-globin gene was modified by introducing a DNA fragment containing the 5' splice region of the large intron upstream or downstream of its natural counterpart. Analogous constructions were carried out with the 3' splice region. The genes were linked to SV40 DNA, transiently expressed in HeLa cells and the transcripts analyzed by S1 mapping. In all cases, the splice site further removed from the intron was utilized to the complete exclusion of its counterpart. This finding argues persuasively against a simple scanning model of RNA splicing, in which the splicing enzyme(s) attaches at the 'donor' spliced region and moves along the intron until it encounters the closest 'acceptor' splice region. A model compatible with the currently known facts is presented.

Base Sequence↗
PubMed1981

Structure of the chicken apo very low density lipoprotein II gene.

We describe two cloned genomic DNA fragments, both bearing the entire apo very low density lipoprotein II gene. Electron microscopy and restriction enzyme mapping showed that this gene is split into at least four coding sequences by three or more intervening sequences. A very short exon at the 5'-end of the gene is separated by a 1.5-kilobase intron from the second exon, which codes for the AUG initiation codon of the mRNA.

Animals↗
PubMed1981

The nucleotide sequence of the very low density lipoprotein II mRNA from chicken.

The nucleotide sequence of an almost complete, double-stranded cDNA of chicken Very Low Density Lipoprotein II mRNA, carried in recombinant plasmid pVLDLII 3.33 (Wieringa et al., 1979, 7: 2147-2163) is presented. A stretch of 318 nucleotides codes for the pre-VLDLII polypeptide, which consists of a 24 amino acids signal and a 82 amino acids secreted protein. The coding stretch is flanked by 57 nucleotides in the 5'-leader sequence of the mRNA, and 258 nucleotides in the 3'-non-coding region. Hypothetical self-complementary structures of parts of the mRNA are presented.

Animals↗
PubMed1981

Translation in vivo and in vitro of mRNAs coding for vitellogenin, serum albumin and very-low-density lipoprotein II from chicken liver. A difference in translational efficiency.

Characterisation of polysomes from estrogenized chicken liver revealed that very-low-density lipoprotein II (VLDLII), serum albumin and vitellogenin mRNAs are differently packed with ribosomes during translation in vivo. Tne ribosome density per number of nucleotides is high for VLDLII mRNA, intermediate for serum albumin mRNA and low for vitellogenin mRNA. This difference in ribosomal load is maintained throughout the period of hormone effect. The differential utilisation observed for vitellogenin and VLDLII mRNAs partly explains the large difference in molar production rate between these yolk protein precursors. Translation properties and efficiency of the three hepatic mRNAs were also compared in the mRNA-depleted reticulocyte lysate. Elongation of the nascent chains for vitellogenin and serum albumin proceeded in a discontinuous fashion. Initiation in vitro was studied at varying ionic strengths, in the presence of aurintricarboxylic acid, and at suboptimal hemin concentrations. VLDLII mRNA expression is by far the most resistant to 7-methylguanosine 5'-triphosphate (m7GTP) and high salt concentrations, vitellogenin mRNA the least. This behaviour resembles the differential utilisation of the mRNAs in vivo. The putative structural basis of these differences is discussed.

Animals↗