Characterization of cuticle collagens and their biosynthetic process in C. elegans sensory ray morphogenesis

There is no doubt that the immense amount of information that is being generated by the initial sequencing and secondary interrogation of various genomes will change the face of glycobiological research. However, a major area of concern is that detailed structural knowledge of the ultimate products of genes that are identified as being involved in glycoconjugate biosynthesis is still limited. This is illustrated clearly by the nematode worm Caenorhabditis elegans, which was the first multicellular organism to have its entire genome sequenced. To date, only limited structural data on the glycosylated molecules of this organism have been reported. Our laboratory is addressing this problem by performing detailed MS structural characterization of the N-linked glycans of C. elegans; high-mannose structures dominate, with only minor amounts of complex-type structures. Novel, highly fucosylated truncated structures are also present which are difucosylated on the proximal N-acetylglucosamine of the chitobiose core as well as containing unusual Fucα1–2Gal1–2Man as peripheral structures. The implications of these results in terms of the identification of ligands for genomically predicted lectins and potential glycosyltransferases are discussed in this chapter. Current knowledge on the glycomes of other model organisms such as Dictyostelium discoideum, Saccharomyces cerevisiae and Drosophila melanogaster is also discussed briefly.

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Faculty Opinions recommendation of Characterization of HCP-6, a C. elegans protein required to prevent chromosome twisting and merotelic attachment.

Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature ◽

10.3410/f.1007263.90256 ◽

2002 ◽

Author(s):

Tatsuya Hirano

Keyword(s):

C Elegans

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Faculty Opinions recommendation of Characterization of HCP-6, a C. elegans protein required to prevent chromosome twisting and merotelic attachment.

Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature ◽

10.3410/f.1007263.99606 ◽

2002 ◽

Author(s):

Robin Allshire

Keyword(s):

C Elegans

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Characterization of Caenorhabditis elegans Homologs of the Down Syndrome Candidate Gene DYRK1A

Genetics ◽

10.1093/genetics/163.2.571 ◽

2003 ◽

Vol 163 (2) ◽

pp. 571-580 ◽

Cited By ~ 1

Author(s):

William B Raich ◽

Celine Moorman ◽

Clay O Lacefield ◽

Jonah Lehrer ◽

Dusan Bartsch ◽

...

Keyword(s):

Down Syndrome ◽

Caenorhabditis Elegans ◽

Trisomy 21 ◽

Gene Dosage ◽

Inducible Promoters ◽

C Elegans ◽

Dual Specificity ◽

Specificity Protein

Abstract The pathology of trisomy 21/Down syndrome includes cognitive and memory deficits. Increased expression of the dual-specificity protein kinase DYRK1A kinase (DYRK1A) appears to play a significant role in the neuropathology of Down syndrome. To shed light on the cellular role of DYRK1A and related genes we identified three DYRK/minibrain-like genes in the genome sequence of Caenorhabditis elegans, termed mbk-1, mbk-2, and hpk-1. We found these genes to be widely expressed and to localize to distinct subcellular compartments. We isolated deletion alleles in all three genes and show that loss of mbk-1, the gene most closely related to DYRK1A, causes no obvious defects, while another gene, mbk-2, is essential for viability. The overexpression of DYRK1A in Down syndrome led us to examine the effects of overexpression of its C. elegans ortholog mbk-1. We found that animals containing additional copies of the mbk-1 gene display behavioral defects in chemotaxis toward volatile chemoattractants and that the extent of these defects correlates with mbk-1 gene dosage. Using tissue-specific and inducible promoters, we show that additional copies of mbk-1 can impair olfaction cell-autonomously in mature, fully differentiated neurons and that this impairment is reversible. Our results suggest that increased gene dosage of human DYRK1A in trisomy 21 may disrupt the function of fully differentiated neurons and that this disruption is reversible.

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Functional Characterization of the Adenylyl Cyclase Genesgs-1by Analysis of a Mutational Spectrum inCaenorhabditis elegans

Genetics ◽

10.1093/genetics/161.1.133 ◽

2002 ◽

Vol 161 (1) ◽

pp. 133-142 ◽

Cited By ~ 4

Author(s):

Celine Moorman ◽

Ronald H A Plasterk

Keyword(s):

Life Span ◽

Adenylyl Cyclase ◽

Neuronal Degeneration ◽

Functional Characterization ◽

Adenylyl Cyclases ◽

Loss Of Function ◽

C Elegans ◽

Larval Stages ◽

Pharyngeal Pumping

AbstractThe sgs-1 (suppressor of activated Gαs) gene encodes one of the four adenylyl cyclases in the nematode C. elegans and is most similar to mammalian adenylyl cyclase type IX. We isolated a complete loss-of-function mutation in sgs-1 and found it to result in animals with retarded development that arrest in variable larval stages. sgs-1 mutant animals exhibit lethargic movement and pharyngeal pumping and (while not reaching adulthood) have a mean life span that is >50% extended compared to wild type. An extensive set of reduction-of-function mutations in sgs-1 was isolated in a screen for suppressors of a neuronal degeneration phenotype induced by the expression of a constitutively active version of the heterotrimeric Gαs subunit of C. elegans. Although most of these mutations change conserved residues within the catalytic domains of sgs-1, mutations in the less-conserved transmembrane domains are also found. The sgs-1 reduction-of-function mutants are viable and have reduced locomotion rates, but do not show defects in pharyngeal pumping or life span.

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Isolation and Characterization of Strain Exiguobacterium sp. KRL4, a Producer of Bioactive Secondary Metabolites from a Tibetan Glacier

Microorganisms ◽

10.3390/microorganisms9050890 ◽

2021 ◽

Vol 9 (5) ◽

pp. 890

Author(s):

Pietro Tedesco ◽

Fortunato Palma Esposito ◽

Antonio Masino ◽

Giovanni Andrea Vitale ◽

Emiliana Tortorella ◽

...

Keyword(s):

Phenotypic Analysis ◽

Biological Assays ◽

C Elegans ◽

Isolation And Characterization ◽

Wide Range ◽

Protein Encoding ◽

Nematocidal Activity ◽

Extremophilic Microorganisms ◽

Unique Source

Extremophilic microorganisms represent a unique source of novel natural products. Among them, cold adapted bacteria and particularly alpine microorganisms are still underexplored. Here, we describe the isolation and characterization of a novel Gram-positive, aerobic rod-shaped alpine bacterium (KRL4), isolated from sediments from the Karuola glacier in Tibet, China. Complete phenotypic analysis was performed revealing the great adaptability of the strain to a wide range of temperatures (5–40 °C), pHs (5.5–8.5), and salinities (0–15% w/v NaCl). Genome sequencing identified KRL4 as a member of the placeholder genus Exiguobacterium_A and annotation revealed that only half of the protein-encoding genes (1522 of 3079) could be assigned a putative function. An analysis of the secondary metabolite clusters revealed the presence of two uncharacterized phytoene synthase containing pathways and a novel siderophore pathway. Biological assays confirmed that the strain produces molecules with antioxidant and siderophore activities. Furthermore, intracellular extracts showed nematocidal activity towards C. elegans, suggesting that strain KRL4 is a source of anthelmintic compounds.

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