Berninsone P et al. (2000) East Coast Worm Meeting "SQV-7, a protein involved in vulval invagination and embryonic development, transports UDP-glucuronic acid, UDP-N-acetylgalactosamine and UDP-galactose"

Hwang H-Y, Horvitz R, Berninsone P, Hirschberg C

[East Coast Worm Meeting, 2000]

Mutations in eight sqv (squashed vulva) genes (sqv-1 to 8) cause defects in vulval invagination and early embryonic development (1). SQV-1 and SQV-4 are similar to enzymes involved in nucleotide sugar metabolism (2), while SQV-3 and SQV-8 are similar to glycosyltransferases (3). SQV-7 is a multi-transmembrane protein resembling Golgi membrane nucleotide sugar transporters (4); these proteins specifically translocate nucleotide sugars from the cytosol into the lumen of the endoplasmic reticulum and Golgi apparatus where they are used as sugar donors by glycosyltransferases (4). Translocation is essential for glycosylation: yeast, protozoa and mammalian cell mutants defective in this function have a severe deficiency of the corresponding sugar in their glycoconjugates (4). Because GDP-mannose and UDP-glucose are the only nucleotide sugars transported into S.cerevisiae Golgi and ER vesicles in vivo and in vitro (5), this organism was used for expression of SQV-7 to determine its substrate specificity. We found that SQV-7 transports UDP-glucuronic acid, UDP-N-acetylgalactosamine and UDP-galactose in vitro, the first protein known to transport the former two nucleotide sugars. All three nucleotide derivatives are competitive, alternate, non-cooperative substrates, which suggests there is a single active site for all three substrates on SQV-7. Expression of the two mutant sqv-7 missense alleles results in significant reduction of the three transport activities. We hypothetize that in these mutants the biosynthesis of chondroitin, the major glycosaminoglycan in C. elegans (6), is more likely to be impaired than that of heparan sulfate since chondroitin polymerization requires both UDP-glucuronic acid and UDP-N-acetylgalactosamine while heparan sulfate polymerization does not require UDP-N-acetylgalactosamine. (1)Herman T. et al (1999) PNAS 96:968 (2)Hwang H. et al.(2000) East Coast C.elegans Meeting (3)Herman T. and Horvitz H. R. (1999) PNAS 96: 974 (4)Hirschberg C. et al (1998) Annu. Rev. Biochem.67: 49 (5)Berninsone P. et al (1997) J. Biol. Chem. 272: 12616 (6)Toyoda H. et al (2000) J. Biol. Chem. 275: 2269

J Grabitzki et al. (2004) European Worm Meeting "THE PCOME OF CAENORHABDITIS ELEGANS IDENTIFICATION OF PHOSPHORYLCHOLINE-SUBSTITUTED PROTEINS AND COMPARISON OF DEVELOPMENTAL CHANGES IN THE EXPRESSION OF THIS EPITOPE"

R Geyer, G Lochnit, J Grabitzki

[European Worm Meeting, 2004]

Caenorhabditis elegans has been found to be good model system for parasitic nematodes, drug screening and developmental studies. Like the respective parasitic worms, C. elegans expresses glycosphingolipids and glycoproteins, carrying, in part, phosphorylcholine (PC) substitutents, which might play important roles in nematode development, fertility and, at least in the case of parasites, the survival within the host (1). With the exception of a major secretory/ excretory product from Achanthocheilonema viteae (ES-62) (2) and the aspartyl-protease ASP-6 (3), no other proteins carrying this epitope has been identified and studied in detail yet. For C. elegans two N-linked PC-epitopes have been reported so far: (I) a pentamannosyl-core structure carrying three PC-residues (4) and (II) a trimannosyl-core species elongated by a N-acetylglucosamine substituted at C-6 with PC (5). Furthermore, in Dauer larvae of C. elegans there was evidence for the presence of glycans with the composition PC1Hex3HexNAc3 to PC2dHex2Hex4HexNAc7 (6). Here we present the 2D-electrophoretic separation of C. elegans proteins, the comparison of the PC-substitution pattern in distinct developmental stages and the mass spectrometric identification of PC-modified proteins. References: 1.Lochnit, G., Dennis, R. D., and Geyer, R. (2000) Biol Chem 381, 839-847 2.Harnett, W., Harnett, M. M., and Byron, O. (2003) Curr Protein Pept Sci 4, 59-71 3.Lochnit, G., Grabitzki, J., Henkel, B., and Geyer, R. (2003) Biochemical Journal submitted 4.Cipollo, J. F., Costello, C. E., and Hirschberg, C. B. (2002) J Biol Chem 277, 49143-49157 5.Haslam, S. M., Gems, D., Morris, H. R., and Dell, A. (2002) Biochem. Soc. Symp. 69, 117-134 6.Cipollo, J. F., Awad, A., Costello, C. E., Robbins, P. W., and Hirschberg, C. B. (2004) Proc Natl Acad Sci U S A 101, 3404-3408

Berninsone P et al. (2000) East Coast Worm Meeting "Defects in glycosaminoglycan biosynthesis cause the C. elegans Sqv phenotype and human Ehlers-Danlos syndrome"

Herman T, Hirschberg C, Hwang H-Y, Horvitz R, Berninsone P

[East Coast Worm Meeting, 2000]

Mutations in eight sqv (squashed vulva) genes result in several developmental abnormalities, including defective vulval invagination and maternal-effect lethality. The molecular identities of the six sqv genes cloned to date now suggest that the molecular basis for these defects lies in the disruption of the biosynthesis of glycosaminoglycans (GAG) of the structure (serine residue in the protein core)-xylose-galactose-galactose-glucuronic acid-(X-glucuronic acid)n, where X is either N-acetylgalactosamine or N-acetylglucosamine. Biosynthesis of GAGs requires the synthesis of nucleotide sugars in the cytoplasm and translocation of nucleotide sugars into the endoplasmic reticulum (ER) and/or Golgi, where polymerization of sugars is catalyzed by glycosyltransferases. SQV-4 is a UDP-glucose dehydrogenase, a key enzyme in UDP-glucuronic acid synthesis. SQV-7 is a multi-pass transmembrane protein that transports UDP-glucuronic acid, UDP-N-acetylgalactosamine and UDP-galactose from the cytoplasm into the ER and/or Golgi (see abstract by Berninsone et al.). Recently cloned mammalian homologs of sqv-3 and sqv-8 encode glycosyltransferases necessary for the biosynthesis of the GAG-protein linkage region of proteoglycans. SQV-3 is similar to galactosyltransferase I, and SQV-8 is similar to glucuronyltransferase I. SQV-1 is a cytoplasmic protein with weak similarities to nucleotide-sugar modifying enzymes, and SQV-5 is a novel protein with a single predicted transmembrane domain. We postulate that sqv-1 and sqv-5 are components of the same GAG biosynthesis pathway and that the GAGs are important for cell-cell or cell-matrix interactions in embryonic and vulval development. Mutations in the human homolog of sqv-3 are implicated as the cause of a progeroid variant of the connective-tissue disorder Ehlers-Danlos syndrome. The other five sqv genes also have close human counterparts, which suggest that a common pathway for modifying important cell surface and/or extracellular GAGs is present in humans and in C. elegans. Defects in the human counterparts of other sqv genes therefore may be responsible for aging disorders and connective tissue diseases such as Ehlers-Danlos syndrome.

Julia Grabitzki et al. (2006) European Worm Meeting "Phosphorylcholine-Modified Proteins of Caenorhabditis elegans are Specific to Developmental Stages"

Michael Ahrend, Gunter Lochnit, Julia Grabitzki, Rudolf Geyer

[European Worm Meeting, 2006]

Julia Grabitzki, Michael Ahrend, Rudolf Geyer and Gunter Lochnit. The free-living nematode Caenorhabditis elegans has been found to be an excellent model system for developmental studies [1] investigating parasitic nematodes [2] and drug screening [3]. Structural analyses of glycoconjugates derived from this organism revealed the presence of nematode specific glycosphingolipids of the arthro-series, carrying, in part, phosphorylcholine (PC) substituents [2]. PC, a small haptenic molecule, is found in a wide variety of prokaryotic organisms, i. e. bacteria, and in eukaryotic parasites such as nematodes. There is evidence that PC-substituted proteins glycolipids are assumed to be responsible for a variety of immunological effects including invasion mechanisms and long-term persistence of parasites within the host [4]. In contrast to PC-modified glycosphingolipids [5], only a limited number of PC-carrying (glyco)proteins were identified so far [6-9]. We have analysed the expression of PC-modified proteins of C. elegans during developmental stages using two dimensional SDS-Page separation, 2D-Western-blot and MALDI-TOF mass spectrometry. The pattern of PC-modified proteins was found to be stage specific. The PC-modification on proteins was most abundant in the egg and dauer larvae-stages followed by the adult-stage and L4. Only small amounts of the PC-substitution were found in L3 and L2. In L1 we couldnt detect any PC-Modification. The prediction of the cellular localisation of the identified proteins revealed a predominant cytosolic and mitochondrial occurrence of the PC- modification. Most of the identified proteins are involved in metabolism or in protein synthesis.. 1.. Brenner, S., Genetics, 1974. 77(1): p. 71-94.. 2.. Lochnit, G., R.D. Dennis, and R. Geyer, Biol Chem, 2000. 381(9-10): p. 839-47.. 3.. Lochnit, G., R. Bongaarts, and R. Geyer, Int J Parasitol, 2005. 35(8): p. 911-23.. 4.. Harnett, W. and M.M. Harnett, Mod. Asp. Immunobiol., 2000. 1(2): p. 40-42.. 5.. Friedl, C.H., G. Lochnit, R. Geyer, M. Karas, and U. Bahr, Anal Biochem, 2000. 284(2): p. 279-87.. 6.. Haslam, S.M., H.R. Morris, and A. Dell, Trends Parasitol, 2001. 17(5): p. 231-5.. 7.. Cipollo, J.F., C.E. Costello, and C.B. Hirschberg, J Biol Chem, 2002. 277(51): p. 49143-57.. 8.. Cipollo, J.F., A.M. Awad, C.E. Costello, and C.B. Hirschberg, J Biol Chem, 2005. 280(28): p. 26063-72.

Zhao Y et al. (2007) BMC Genomics "Poly-G/poly-C tracts in the genomes of Caenorhabditis."

Zhao Y, O'Neil NJ, Rose AM

[BMC Genomics, 2007]

ABSTRACT: BACKGROUND: In the genome of Caenorhabditis elegans, homopolymeric poly-G/poly-C tracts (G/C tracts) exist at high frequency and are maintained by the activity of the DOG-1 protein. The frequency and distribution of G/C tracts in the genomes of C. elegans and the related nematode, C. briggsae were analyzed to investigate possible biological roles for G/C tracts. RESULTS: In C. elegans, G/C tracts are distributed along every chromosome in a non-random pattern. Most G/C tracts are within introns or are close to genes. Analysis of SAGE data showed that G/C tracts correlate with the levels of regional gene expression in C. elegans. G/C tracts are over-represented and dispersed across all chromosomes in another Caenorhabditis species, C. briggase. However, the positions and distribution of G/C tracts in C. briggsae differ from those in C. elegans. Furthermore, the C. briggsae dog-1 ortholog CBG19723 can rescue the mutator phenotype of C. elegans dog-1 mutants. CONCLUSIONS: The abundance and genomic distribution of G/C tracts in C. elegans, the effect of G/C tracts on regional transcription levels, and the lack of positional conservation of G/C tracts in C. briggsae suggest a role for G/C tracts in chromatin structure but not in the transcriptional regulation of specific genes.

Bhagwati P Gupta et al. (2002) West Coast Worm Meeting "Genetic analysis of the vulval mutants in C. briggsae"

Shahla Gharib, Bhagwati P Gupta, Paul W Sternberg, Jennifer X Li

[West Coast Worm Meeting, 2002]

To understand the evolution of developmental mechanisms, we are doing a comparative analysis of vulval patterning in C. elegans and C. briggsae. C. briggsae is closely related to C. elegans and has identical looking vulval morphology. However, recent studies have indicated subtle differences in the underlying mechanisms of development. The recent completion of C. briggsae genome sequence by the C. elegans Sequencing Consortium is extremely valuable in identifying the conserved genes between C. elegans and C. briggsae.

Antika TR et al. (2023) J Biol Chem "Sequence-specific targeting of C. elegans C-Ala to the D-loop of tRNAAla."

Horng JC, Hsu HL, Nazilah KR, Wang CC, Wang TL, Wang SC, Antika TR, Chuang TH, Chrestella DJ, Wang SW, Tseng YK, Pan HC

[J Biol Chem, 2023]

Alanyl-tRNA synthetase (AlaRS) retains a conserved prototype structure throughout its biology. Nevertheless, its C-terminal domain (C-Ala) is highly diverged and has been shown to play a role in either tRNA or DNA binding. Interestingly, we discovered that Caenorhabditis elegans cytoplasmic C-Ala (Ce-C-Ala_c) robustly binds both ligands. How Ce-C-Ala_c targets its cognate tRNA and whether a similar feature is conserved in its mitochondrial counterpart remain elusive. We show that the N- and C-terminal subdomains of Ce-C-Ala_c are responsible for DNA and tRNA binding, respectively. Ce-C-Ala_c specifically recognized the conserved invariant base G¹⁸ in the D-loop of tRNA^Ala through a highly conserved lysine residue, K934. Despite bearing little resemblance to other C-Ala domains, C. elegans mitochondrial C-Ala (Ce-C-Ala_m) robustly bound both tRNA^Ala and DNA and maintained targeting specificity for the D-loop of its cognate tRNA. This study uncovers the underlying mechanism of how C. elegans C-Ala specifically targets the D-loop of tRNA^Ala.

Blumenthal TE et al. (1994) Worm Breeder's Gazette "C. elegans U2AF 65."

Zorio DAR, Lea K, Blumenthal TE

[Worm Breeder's Gazette, 1994]

C. elegans U2AF65

Oomura, S. et al. (2019) International Worm Meeting "Early embryogenesis of C. inopinata, a sibling species of C.elegans."

Matsumura, Y., Haruta, N., Hoshi, Y., Sugimoto, A., Oomura, S.

[International Worm Meeting, 2019]

C. inopinata is a newly discovered sibling species of C. elegans. Despite their phylogenetic closeness, they have many differences in morphology and ecology. For example, while C. elegans is hermaphroditic, C. inopinata is gonochoristic; C. inopinata is nearly twice as long as C. elegans. A comparative analysis of C. elegans and C. inopinata enables us to study how genomic changes cause these phenotypic differences. In this study, we focused on early embryogenesis of C. inopinata. First, by the microparticle bombardment method we made a C. inopinata line that express GFP::histone in whole body, and compared the early embryogenesis with C. elegans by DIC and fluorescent live imaging. We found that the position of pronuclei and polar bodies were different between these two species. In C. elegans, the female and male pronuclei first become visible in anterior and posterior sides, respectively, then they meet at the center of embryo. On the other hand, the initial position of pronuclei were more closely located in C. inopinata. Also, the polar bodies usually appear in the anterior side of embryo in C. elegans, but they appeared at random positions in C. inopinata. Therefore, we infer that C. inopinata may have a different polarity formation mechanism from that in C. elegans. We are also analyzing temperature dependency of embryogenesis in C. inopinata, whose optimal temperature is ~7 degree higher than that in C. elegans.

Guven K (1995) Journal of Thermal Biology "Differential expression of hsp70 proteins in response to heat and cadmium in Caenorhabditis elegans."

Guven K

[Journal of Thermal Biology, 1995]

1. The patterns of HSP70 expression induced in Caenorhabditis elegans by mild (31 degrees C) or severe (34 degrees C) heat shock, and by cadmium ions at 31 degrees C, have been compared with those expressed constitutively ill 20 degrees C controls by 1- and a-dimensional immunoblotting. 2. The 2D spot patterns become more complex with increasing severity of stress (34 degrees C > 31 degrees C + Cd > 31 degrees C > 20 degrees C). 3. A stress-inducible transgene construct is minimally active at 31 degrees C, but is abundantly expressed in the presence of cadmium or at 34 degrees C. 4. Differing degrees or types of stress may differentially induce available hsp70