McGhee JD (1987) Biochemistry "Purification and characterization of a carboxylesterase from the intestine of the nematode Caenorhabditis elegans."

McGhee JD

[Biochemistry, 1987]

The major intestinal esterase from the nematode Caenorhabditis elegans has been purified to essential homogeneity. Starting from whole worms, the overall purification is 9000-fold with a 10% recovery of activity. The esterase is a single polypeptide chain of Mr 60,000 and is stoichiometrically inhibited by organophosphates. Substrate preferences and inhibition patterns classify the enzyme as a carboxylesterase (EC 3.1.1.1), but the physiological function is unknown. The sequence of 13 amino acid residues at the esterase N- terminus has been determined. This partial sequence shows a surprisingly high degree of similarity to the N-terminal sequence of two carboxylesterases recently isolated from Drosophila mojavensis [Pen, J., van Beeumen, J., & Beintema, J. J. (1986) Biochem. J. 238, 691-699].

Murakami S et al. (1999) Curr Biol "Life extension and stress resistance in Caenorhabditis elegans modulated by the tkr-1 gene."

Johnson TE, Murakami S

[Curr Biol, 1999]

In this Brief Communication, which appeared in the 14 September 1998 issue of Current Biology, the UV dose was reported erroneously. The dose reported was 20 J/m2 but the actual dose used was 0.4 J/cm2. Also, the gene formally referred to as tkr-1 has since been renamed old-1 (overexpression longevity determination).

Nillegoda NB et al. (2015) Nature "Crucial HSP70 co-chaperone complex unlocks metazoan protein disaggregation."

Nillegoda NB, Wade RC, Szlachcic A, Morimoto RI, Guilbride DL, Berynskyy M, Kirstein J, Gao X, Arnsburg K, Aebersold R, Bukau B, Mayer MP, Stengel F, Stank A, Scior A

[Nature, 2015]

Protein aggregates are the hallmark of stressed and ageing cells, and characterize several pathophysiological states. Healthy metazoan cells effectively eliminate intracellular protein aggregates, indicating that efficient disaggregation and/or degradation mechanisms exist. However, metazoans lack the key heat-shock protein disaggregase HSP100 of non-metazoan HSP70-dependent protein disaggregation systems, and the human HSP70 system alone, even with the crucial HSP110 nucleotide exchange factor, has poor disaggregation activity in vitro. This unresolved conundrum is central to protein quality control biology. Here we show that synergic cooperation between complexed J-protein co-chaperones of classes A and B unleashes highly efficient protein disaggregation activity in human and nematode HSP70 systems. Metazoan mixed-class J-protein complexes are transient, involve complementary charged regions conserved in the J-domains and carboxy-terminal domains of each J-protein class, and are flexible with respect to subunit composition. Complex formation allows J-proteins to initiate transient higher order chaperone structures involving HSP70 and interacting nucleotide exchange factors. A network of cooperative class A and B J-protein interactions therefore provides the metazoan HSP70 machinery with powerful, flexible, and finely regulatable disaggregase activity and a further level of regulation crucial for cellular protein quality control.

Ramos CG et al. (2014) J Bacteriol "Retraction for Ramos et al., MtvR is a global small noncoding regulatory RNA in Burkholderia cenocepacia."

Leitao JH, da Costa PJ, Grilo AM, Feliciano JR, Ramos CG

[J Bacteriol, 2014]

Volume 195, no. 16, p. 35143523, 2013. A number of problems related to images published in this paper have been brought to our attention. Figure 1D contains duplicated images in lanes S and LE, and Fig. 4D and 6B contain images previously published in articles in this journal and in Microbiology and Microbial Pathogenesis, i.e., the following: C. G. Ramos, S. A. Sousa, A. M. Grilo, J. R. Feliciano, and J. H. Leitao, J. Bacteriol. 193:15151526, 2011. doi:10.1128/JB.01374-11. S. A. Sousa, C. G. Ramos, L. M. Moreira, and J. H. Leitao, Microbiology 156:896908, 2010. doi:10.1099/mic.0.035139-0. C. G. Ramos, S. A. Sousa, A. M. Grilo, L. Eberl, and J. H. Leitao, Microb. Pathog. 48:168177, 2010. doi: 10.1016/j.micpath.2010.02.006. Therefore, we retract the paper. We deeply regret this situation and apologize for any inconvenience to the editors and readers of Journal of Bacteriology, Microbial Pathogenesis, and Microbiology.

Miller DM et al. (1992) Worm Breeder's Gazette "unc-4 LacZ Expression in A-Type Motor Neurons"

Miller DM, Niemeyer CJ

[Worm Breeder's Gazette, 1992]

unc-4 LacZ expression in A-type motor neurons David M. Miller and Charles J. Niemeyer, Dept. of Cell Biology, Duke Univ. Medical Ctr, Durham, NC 27710

J Duerr et al. (1999) International C. elegans Meeting "Chromogranin A Immunoreactivity in C. elegans"

L Eiden, J Gaskin, J Rand, J Duerr

[International C. elegans Meeting, 1999]

Chromogranin A (CGA) is the most abundant protein in chromaffin granules, catecholamine-containing vesicles of the mammalian adrenal medulla. It is also widespread in the nervous system and in a number of other endocrine tissues. CGA is believed to be a pro-hormone, comprising more than one peptide (neuro)hormone. In addition, its biochemical properties have led to the suggestion that it may also have intracellular roles. Antibodies to CGA have identified a related sequence in at least one invertebrate, the lobster (Rieker et al.). Antibodies against a portion of CGA have also been used on Ascaris suum (Brownlee et al.), where immunoreactivity was found in the ventral and lateral nerve cords. However, no sequence highly homologous to CGA has yet been described by the sequencing consortium. We have used antibodies against two peptides derived from vertebrate CGA to examine the distribution of related peptides in C. elegans . Antibodies to both CGA peptides recognize a number of bands on Westerns, including a shared band of the appropriate size for CGA. Like bonafide CGA, this protein is resistant to boiling. However, antibodies against the two peptides give different patterns on fixed worms. An antibody against the N-terminal peptide strongly labels a subset of neurons in the head ganglia, including some sensory neurons. unc-104 mutants, in which synaptic vesicles and proteins are mislocalized in cell bodies, show an enrichment of anti-CGA in a subset of neuronal somas. This is consistent with the CGA-like immunoreactivity being enriched in synaptic vesicles, as would be expected for a neuropeptide. On the other hand, antibodies to a peptide from the middle of the protein label most neurons in a uniform way and this staining is not altered in unc-104 mutants. We are currently trying to understand this difference in pattern and to determine whether the antigens recognized by the anti-CGA antibodies reflect the distribution of proteins or peptides with CGA-related functions. This work was supported by grants from OCAST and NIH.

J Duerr et al. (1999) International C. elegans Meeting "Development of Neurotransmitter Phenotypes in the VC Motor Neurons"

J Duerr, J Rand, J Gaskin, D Frisby

[International C. elegans Meeting, 1999]

The VC neurons are a class of six post-embryonic motor neurons with synapses on the vulva muscles, other body muscles, and a few other motor neurons (White et al.). In late L4, all six VCs develop FMRFamide-like immunoreactivity (Schinkmann and Li) and some are induced to branch by the vulva (Li and Chalfie). We have used specific antibodies to determine that some of the VCs probably use acetylcholine and a monoamine as well as a FMRFamide-like peptide as neurotransmitters. The antibodies we used were generated against synaptic proteins, so they only weakly label cell bodies (whose position aids greatly in cell identification). Therefore, we used unc-104 mutants (in which synaptic proteins are mislocalized in somas) as well as over-expressing transgenic lines (in which 'excess' protein is found in somas) to identify neurons. In adults, all of the VCs are usually labeled with antibodies to two cholinergic markers, the acetylcholine synthetic enzyme choline acetyltransferase (ChAT, encoded by cha-1 ) and the vesicular acetylcholine transporter (VAChT, encoded by unc-17 ). VC4 and VC5, but not the other VCs, are also labeled with antibodies to a monoaminergic marker, the vesicular monoamine transporter (VMAT, encoded by cat-1 ). Antibodies to ChAT, VAChT, and VMAT label the VC motor neurons in slightly different patterns spatially and temporally. When the VCs are born in late L1, they do not exhibit detectable cholinergic or aminergic immunoreactivity. This is consistent with the expression pattern of other post-embryonic cholinergic neurons. During larval development, the intensity of cholinergic immunoreactivity increases fairly uniformly in most post-embryonic ventral nerve cord cholinergic neurons. However, some of the VCs continue to lack detectable immunoreactivity or express very low and variable levels. As the vulva develops, ChAT and VMAT immunoreactivity greatly increase in VC4 and VC5 and increase slightly in some of the other VCs. This is followed by expression of VMAT in VC4 and VC5 (but not in the other VCs). We are studying the temporal and spatial patterns of these and other late VC markers to try and understand their regulation and relevance. This work was supported by grants from OCAST and NIH.

Sommer RJ et al. (1994) Worm Breeder's Gazette "Evolution of Vulva-Formation: Part II: Species With a Central Vulva"

Sternberg PW, Sommer RJ

[Worm Breeder's Gazette, 1994]

Evolution of vulva-formation: Part II: Species with a central vulva Ralf J. Sommer & Paul W. Sternberg, California Institute of Technology, Division of Biology 156-29, Pasadena, CA 91125

Jun-ichi Aikawa (2001) International C. elegans Meeting "Molecular characterization of heparan sulfate/heparin N-deacetylase/N-sulfotransferase in worms"

Jun-ichi Aikawa

[International C. elegans Meeting, 2001]

Heparan sulfate binds and activates a large variety of growth factors, enzymes and extracellular matrix proteins. These interactions largely depend on the specific arrangement of sulfated moieties and uronic acid epimers within the chains. These oligosaccharide sequences are generated in a step-wise manner, initiated by the formation of a linkage tetrasaccharide which is then extended by copolymerization of alternating a1,4GlcNAc and b1,4GlcA residues. As the chains polymerize, they undergo a series of sulfation and epimerization reactions. The first set of modifications involves the removal of acetyl units from subsets of GlcNAc residues, and the addition of sulfate groups to the resulting free amino groups. These reactions are catalyzed by a family of enzymes designated as GlcNAc N-deacetylase/N-sulfotransferases (NDST), since they simultaneously. Four members of the family have been identified in vertebrates, with single orthologs present in Drosophila and C. elegans. We have revealed tissue-specific expression pattern and unique enzymatic properties of these four isozymes1,2). In fly, loss of NDST (sulfateless) results in unsulfated chains and defective signaling by multiple growth factors and morphogens. I reconstituted cDNA for worm NDST from EST clones and 5' RACE products. Enzymatic activities will be discussed. 1) Aikawa, J. & Esko, J. D J. Biol. Chem. 274, 2690-2695 (1999) 2) Aikawa, J., Grobe, K., Tsujimoto, M. & Esko, J. D J. Biol. Chem. 276, 5876-5882 (2001)

Dreyfus DH et al. (1999) Mol Immunol "Comparative analysis of invertebrate Tc6 sequences that resemble the vertebrate V(D)J recombination signal sequences (RSS)."

Gelfand EW, Dreyfus DH

[Mol Immunol, 1999]

Invertebrate cells lack the p53 recombination checkpoint but contain mobile DNA sequences that transpose by a mechanism in part shared with excision of the V(D)J recombination signal sequences (RSS). In this work, inversion, deletion, and duplication of sequences associated with an invertebrate C. elegans Tc6 element is described. The structure of this C. elegans sequence and other dispersed Tc6 elements suggests that covalently closed 'hairpin' structures are not unique to excision of the V(D)J RSS by the RAG proteins, but rather can be generated by transposases at transposon termini leading to characteristic inversion and duplication events. Comparative analysis of recombination events at invertebrate sequences resembling the vertebrate V(D)J RSS may be useful in understanding V(D)J recombination-mediated recombination events in malignant vertebrate cells or genetic diseases such as ataxia telangectasia, in which the p53 recombination checkpoint is defective.