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[
Oncogene,
1999]
1q21 is frequently involved in different types of translocation in many types of cancers. Jumping translocation (JT) is an unbalanced translocation that comprises amplified chromosomal segments jumping to various telomeres. In this study, we identified a novel gene human JTB (Jumping Translocation Breakpoint) at 1q21, which fused with the telomeric repeats of acceptor telomeres in a case of JT. hJTB (human JTB) encodes a trans-membrane protein that is highly conserved among divergent eukaryotic species. JT results in a hJTB truncation, which potentially produces an hJTB product devoid of the trans-membrane domain. hJTB is located in a gene-rich region at 1q21, called EDC (Epidermal Differentiation Complex). This is the first report identifying the gene involved in unbalanced translocations at 1q21.
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[
Mol Phylogenet Evol,
1997]
Nematodes are known to be a useful system for studies of comparative development. Here we perform a molecular phylogenetic analysis to allow for the independent interpretation of the developmental and morphological changes observed among a selected set of nematode species. Our molecular phylogenetic analysis is based on coding regions of the genes for RNA polymerase II, the small subunit rRNA and an expansion segment of the large subunit rRNA. Sequences were compared from five species in the family (Rhabditidae) that includes the developmental model organism Caenorhabditis elegans and from an outgroup taxon Aduncospiculum halicti (Diplogasterina). The phylogenetic analysis does not support the monophyly of the subfamily Mesorhabditinae and identifies the unnamed strain PS1010 as a sister taxon of C. elegans despite its morphologically divergent buccal capsule. On the basis of the inferred framework, we can begin to interpret the evolution of vulval development and of morphological differences among these nematode species.
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[
Canadian Journal of Zoology,
1997]
The buccal capsule of Aduncospiculum halicti (Diplogasterina) is compared with that of Zeldia punctata (Cephalobina) and Caenorhabditis elegans (Rhabditina). Characters are mapped on an independent DNA-based phylogenetic tree (inferred from RNA polymerase II and rDNA sequences) to test evolutionary hypotheses. Irrespective of dimorphism, the buccal capsule wall of A. halicti consists of an anterior to posterior series of six cuticular structures classically termed rhabdions. These are defined according to their internal differentiations, discontinuities in profiles, and underlying tissues. Homologies of rhabdions 1 and 2 in A. halicti are proposed on the basis of position and association with adjacent tissues, consistent with those of Cephalobina and Rhabditina. Rhabdion 3 is associated with radial epithelial cells as is the mesorhabdion in C. elegans; this contrasts with Z. punctata, where a rhabdion in a similar position is associated with radial muscle cells. Dorsal and subventral teeth in A. halicti comprise rhabdions 4 and 5; this may be homologous with a corresponding region in Z. punctata but contrasts with C. elegans, where the corresponding region consists of a single metarhabdion. These characters, when mapped on the sequence-based tree, suggest that A. halicti and Diplogasterina share with C. elegans and other Rhabditina derived characters, including a mesorhabdion associated with epithelial cells, but retain some apparently primitive features shared with Cephalobina.
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[
J Neurophysiol,
2015]
Although the ability to detect humidity (i.e., hygrosensation) represents an important sensory attribute in many animal species (including humans), the neurophysiological and molecular bases of such sensory ability remain largely unknown in many animals. Recently, Russell and colleagues (Russell J, Vidal-Gadea AG, Makay A, Lanam C, Pierce-Shimomura JT. Proc Natl Acad Sci USA 111: 8269-8274, 2014) provided for the first time neuromolecular evidence for the sensory integration of thermal and mechanical sensory cues which underpin the hygrosensation strategy of an animal (i.e., the free-living roundworm Caenorhabditis elegans) that lacks specific sensory organs for humidity detection (i.e., hygroreceptors). Due to the remarkable similarities in the hygrosensation transduction mechanisms used by hygroreceptor-provided (e.g., insects) and hygroreceptor-lacking species (e.g., roundworms and humans), the findings of Russell et al. highlight potentially universal mechanisms for humidity detection that could be shared across a wide range of species, including humans.
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Garey JR, Thomas WK, Dorris M, Frisse LM, Vanfleteren JR, De Ley P, Mackey LY, Vierstraete A, Liu LX, Scheldeman P, Blaxter ML, Vida JT
[
Nature,
1998]
Nematodes are important: parasitic nematodes threaten the health of plants, animals and humans on a global scale; interstitial nematodes pervade sediment and soil ecosystems in overwhelming numbers; and Caenorhabditis elegans is a favourite experimental model system. A lack of clearly homologous characters and the absence of an informative fossil record have prevented us from deriving a consistent evolutionary framework for the phylum. Here we present a phylogenetic analysis, using 53 small subunit ribosomal DNA sequences from a wide range of nematodes. With this analysis, we can compare animal-parasitic, plant-parasitic and free-living taxa using a common measurement. Our results indicate that convergent morphological evolution may be extensive and that present higher-level classification of the Nematoda will need revision. We identify five major clades within the phylum, all of which include parasitic species. We suggest that animal parasitism arose independently at least four times, and plant parasitism three times. We clarify the relationship of C. elegans to major parasitic groups; this will allow more effective exploitation of our genetic and biological knowledge of this model species.