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B Winnepenninckx

Publications and source records attributed to B Winnepenninckx.

16 recordsLinked to original sources
PubMed2004

A splice site mutation in the methyltransferase gene FTSJ1 in Xp11.23 is associated with non-syndromic mental retardation in a large Belgian family (MRX9).

Mental retardation is the most frequent cause of serious handicap in children and young adults. The underlying causes of this heterogeneous condition are both acquired and genetically based. A recently performed refinement of the linkage interval in a large Belgian family with mild to severe non-syndromic X linked mental retardation, classified as MRX9, revealed a candidate region of 11.3 Mb between markers DXS228 and DXS1204 on the short arm of the X chromosome. In order to identify the underlying disease gene in the MRX9 family, we established a gene catalogue for the candidate region and performed comprehensive mutation analysis by direct sequencing. A human homologue of the bacterial 23S rRNA methyltransferase Fstj, the FTSJ1 gene, is located within this region and displayed a sequence alteration in the conserved acceptor splice site of intron 3 (IVS3-2A>G) in all tested patients and carrier females of this family. In contrast, it was absent in all unaffected male family members tested. The mutation results in skipping of exon 4 and introduces a premature stop codon in exon 5, probably leading to a severely truncated protein. Our finding indicates that a protein, possibly associated with ribosomal stability, can be linked to X linked mental retardation (XLMR).

Amino Acid Sequence↗
PubMed1998

Characterization of the myoglobin and its coding gene of the mollusc Biomphalaria glabrata.

A cDNA clone isolated from a Biomphalaria glabrata (Mollusca, Gastropoda) neural cDNA library was identified as encoding a myoglobin-like protein of 148 amino acids with a single domain and a calculated mass of 16,049.29. Alignment with globin sequences with known tertiary structure confirms its overall globin nature. The expressed myoglobin was identified in the radular muscle and isolated. Oxygen equilibrium measurements on the protein reveal a high oxygen affinity. Val-B10 and Gln-E7, important residues for the determination of the oxygen affinity, are strikingly different from the standard molluscan pattern (Conti, E., Moser, C., Rizzi, M., Mattevi, A., Lionetti, C., Coda, A., Ascenzi, P., Brunori, M., Bolognesi, M. (1993) J. Mol. Biol. 233, 498-508). The single gene encoding the globin chain is interrupted by three introns at positions A3.2, B12.2, and G7.0. Comparison with other nonvertebrate globin genes reveals on the one hand conservation (B12.2 and G7.0) and on the other hand variability of the insertion positions (A3.2). The Biomphalaria myoglobin sequence was used together with all other molluscan globin sequences available to assess the origin and phylogeny of the phylum. Our results confirm the doubts raised about monophyletic origin of the Mollusca, which was first observed using SSU rRNA as a molecular marker.

Amino Acid Sequence↗
PubMed1998

Details of gastropod phylogeny inferred from 18S rRNA sequences.

Some generally accepted viewpoints on the phylogenetic relationships within the molluscan class Gastropoda are reassessed by comparing complete 18S rRNA sequences. Phylogenetic analyses were performed using the neighbor-joining and maximum parsimony methods. The previously suggested basal position of Archaeogastropoda, including Neritimorpha and Vetigastropoda, in the gastropod clade is confirmed. The present study also provides new molecular evidence for the monophyly of both Caenogastropoda and Euthyneura (Pulmonata and Opisthobranchia), making Prosobranchia paraphyletic. The relationships within Caenogastropoda and Euthyneura data turn out to be very unstable on the basis of the present 18S rRNA sequences. The present 18S rRNA data question, but are insufficient to decide on, muricacean (Neogastropoda), neotaenioglossan, pulmonate, or stylommatophoran monophyly. The analyses also focus on two systellommatophoran families, namely, Veronicellidae and Onchidiidae. It is suggested that Systellommatophora are not a monophyletic unit but, due to the lack of stability in the euthyneuran clade, their affinity to either Opisthobranchia or Pulmonata could not be determined.

Animals↗
PubMed1998

Dependence of the ligation efficiency of large DNA fragments isolated from agarose gels on the purification method.

The isolation of large DNA fragments (> 5 kb) from agarose gels can be problematic. The DNA yield is often low, and the purification may be insufficient for subsequent reactions such as sequencing or ligation. Here we have compared a number of commonly used methods and commercial kits for DNA recovery. Large DNA fragments (12 and 14 kb, respectively) were isolated from agarose gel and purified, the recovery yield was tested, and a well-defined amount of purified DNA was used in a standard ligation reaction. We observed dramatic differences in the efficiency of this ligation reaction depending on which recovery method had been used. However, the respective ligation efficiencies of the different methods were not related to their recovery yields.

Animals↗
PubMed1996

18S rRNA suggests that Entoprocta are protostomes, unrelated to Ectoprocta.

The Ento- and Ectoprocta are sometimes placed together in the Bryozoa, which have variously been regarded as proto- or deuterostomes. However, Entoprocta have also been allied to the pseudocoelomates, while Ectoprocta are often united with the Brachiopoda and Phoronida in the (super)phylum Lophophorata. Hence, the phylogenetic relationships of these taxa are still much debated. We determined complete 18S rRNA sequences of two entoprocts, an ectoproct, an inarticulate brachiopod, a phoronid, two annelids, and a platyhelminth. Phylogenetic analyses of these data show that (1) entoprocts and lophophorates have spiralian, protostomous affinities, (2) Ento- and Ectoprocta are not sister taxa, (3) phoronids and brachiopods form a monophyletic clade, and (4) neither Ectoprocta or Annelida appear to be monophyletic. Both deuterostomous and pseudocoelomate features may have arisen at least two times in evolutionary history. These results advocate a Spiralia-Radialia-based classification rather than one based on the Protostomia-Deuterostomia concept.

Animals↗
PubMed1996

The new generation Siemens Multiline lithotripter tube "M": early results in ureteral calculi.

The Siemens electromagnetic Lithostar tube "C" and the new multiline tube "M" lithotripters were compared for the in situ treatment of ureteral calculi. A series of 248 patients with a calcium oxalate ureteral stone (proven by stone analysis) more than 4 mm in diameter were treated between December 1994 and September 1995 with the tube M Multiline lithotripter. The results were compared with those of 462 patients treated in prior years with tube C. High energy levels were obtained without sedation in 11% of patients with tube C and in 61% with tube M. The proportion of patients needing additional analgetics was 11% and 6%, respectively. The percentages of patients reporting no pain at all were 7 and 77. In proximal calculi, stone-free status was achieved in 63 of 79 patients (80%) with tube C and in 82 of 91 patients (90%) with tube M (p = 0.057). In distal calculi, stone-free status was achieved in 124 of 173 patients (72%) with tube C and in 134 of 157 patients (85%) with tube M (p = 0.0027). The evacuation rate for distal ureteral stones was significantly higher with tube M, which implies that the new shock head can enable the operator to apply higher energy without sedation because of the better tolerance.

Humans↗
PubMed1996

Investigation of molluscan phylogeny on the basis of 18S rRNA sequences.

The 18S rRNA sequences of 12 molluscs, representing the extant classes Gastropoda, Bivalvia, Polyplacophora, Scaphopoda, and Caudofoveata, were determined and compared with selected known 18S rRNA sequences of Metazoa, including other Mollusca. These data do not provide support for a close relationship between Platyhelminthes (Turbellaria) and Mollusca, but rather suggest that the latter group belongs to a clade of eutrochozoan coelomates. The 18S rRNA data fail to recover molluscan, bivalve, or gastropod monophyly. However, the branching pattern of the eutrochozoan phyla and classes is unstable, probably due to the explosive Cambrian radiation during which these groups arose. Similarly, the 18S rRNA data do not provide a reliable signal for the molluscan interclass relationships. Nevertheless, we obtained strong preliminary support for phylogenetic inferences at more restricted taxonomic levels, such as the monophyly of Polyplacophora, Caenogastropoda, Euthyneura, Heterodonta, and Arcoida.

Animals↗
PubMed1995

Phylogeny of protostome worms derived from 18S rRNA sequences.

The phylogenetic relationships of protostome worms were studied by comparing new complete 18S rRNA sequences of Vestimentifera, Pogonophora, Sipuncula, Echiura, Nemertea, and Annelida with existing 18S rRNA sequences of Mollusca, Arthropoda, Chordata, and Platyhelminthes. Phylogenetic trees were inferred via neighbor-joining and maximum parsimony analyses. These suggest that (1) Sipuncula and Echiura are not sister groups; (2) Nemertea are protostomes; (3) Vestimentifera and Pogonophora are protostomes that have a common ancestor with Echiura; and (4) Vestimentifera and Pogonophora are a monophyletic clade.

Animals↗
PubMed1995

18S rRNA data indicate that Aschelminthes are polyphyletic in origin and consist of at least three distinct clades.

The Aschelminthes is a collection of at least eight animal phyla, historically grouped together because the absence of a true body cavity was perceived as a pseudocoelom. Analyses of 18S rRNA sequences from six Aschelminth phyla (including four previously unpublished sequences) support polyphyly for the Aschelminthes. At least three distinct groups of Aschelminthes were detected: the Priapulida among the protostomes, the Rotifera-Acanthocephala as a sister group to the protostomes, and the Nematoda as a basal group to the triploblastic Eumetazoa.

Acanthocephala↗
PubMed1995

CARD: a drawing tool for RNA secondary structure models.

A graphical editor was developed to create publication-quality representations of RNA secondary structure models. A user-defined model can be gradually assembled from structural elements such as helix segments and loops. The type of structural element to be drawn is chosen from a menu. Its nucleotide sequence has to be entered from the keyboard. Afterwards, drawings can be manipulated by moving, deleting, rotating, copying or changing the structural elements separately. An example of a secondary structure model is given for a complete 18S rRNA molecule.

Nucleic Acid Conformation↗