Musset-Bilal F et al. (1994) Worm Breeder's Gazette "Characterization of the C. elegans Basement Membrane-Associated Protein SPARC"

Musset-Bilal F, Schwarzbauer JE, Ryan CS

[Worm Breeder's Gazette, 1994]

Characterization of the C. elegans Basement Membrane- Associated Frederique Musset-Bilal, Carol S. Ryan, and Jean E. Schwarzbauer Department of Molecular Biology, Princeton University, Princeton NJ 08544

Townsend SR et al. (1994) Worm Breeder's Gazette "C. elegans Molecular Genetics and Long PCR."

Finelli AL, Savage C, Xie T, Padgett RW, Townsend SR

[Worm Breeder's Gazette, 1994]

C. elegans Molecular Genetics and Long PCR Scott R. Townsend, Cathy Savage, Alyce L. Finelli, Ting Xie, and Richard W. Padgett, Waksman Institute and Department of Molecular Biology and Biochemistry, Rutgers University, Piscataway, NJ 08855

Bhamidipati A et al. (2000) J Cell Biol "ADP ribosylation factor-like protein 2 (Arl2) regulates the interaction of tubulin-folding cofactor D with native tubulin."

Lewis SA, Cowan NJ, Bhamidipati A

[J Cell Biol, 2000]

The ADP ribosylation factor-like proteins (Arls) are a family of small monomeric G proteins of unknown function. Here, we show that Arl2 interacts with the tubulin-specific chaperone protein known as cofactor D. Cofactors C, D, and E assemble the alpha/beta- tubulin heterodimer and also interact with native tubulin, stimulating it to hydrolyze GTP and thus acting together as a beta-tubulin GTPase activating protein (GAP). We find that Arl2 downregulates the tubulin GAP activity of C, D, and E, and inhibits the binding of D to native tubulin in vitro. We also find that overexpression of cofactors D or E in cultured cells results in the destruction of the tubulin heterodimer and of microtubules. Arl2 specifically prevents destruction of tubulin and microtubules by cofactor D, but not by cofactor E. We generated mutant forms of Arl2 based on the known properties of classical Ras-family mutations. Experiments using these altered forms of Arl2 in vitro and in vivo demonstrate that it is GDP-bound Arl2 that interacts with cofactor D, thereby averting tubulin and microtubule destruction. These data establish a role for Arl2 in modulating the interaction of tubulin-folding cofactors with native tubulin in vivo.

Wilkinson HA et al. (1994) Worm Breeder's Gazette "Reciprocal Changes in Expression of lin-12 and lag-2 Prior to Commitment of Z1.ppp and Z4.aaa."

Greenwald IS, Wilkinson HA, Fitzgerald K

[Worm Breeder's Gazette, 1994]

Reciprocal changes in expression of lin-12 and lag-2 prior to commitment of Z1.ppp and Z4.aaa. Hilary A. Wilkinson*, Kevin Fitzgerald and Iva Greenwald, HHMI and Dept. of Biochemistry and Molecular Biophysics, Columbia University College of Physicians and Surgeons, New York, NY 10032; *Current address: Merck Research Laboratories, Rahway, NJ 07065

Ishii N et al. (1988) Worm Breeder's Gazette "partial sequence of the unc-6 gene."

Ishii N, Stern BD, Culotti JG, Hedgecock EM

[Worm Breeder's Gazette, 1988]

In the previous issue (WBG 10(1) p.35), we reported cloning a small DNA fragment containing the Tc1 insertion which caused the unc-6 ( rh1035) mutation. Since then, we have isolated an 11.5 kb EcoRI fragment including this region from N2 DNA (NJ#14, EMBL4 vector) Alan Coulson has kindly positioned this fragment on the MRC genome map. We have now sequenced both the original 1.25 kb XbaI fragment of unc-6( rh1035) DNA (plasmid NJ#6) and a 2.7 kb HindIII fragment of N2 DNA subcloned from phage NJ#14. The 2.7 kb HindIII fragment has five exons which encode a hypothetical protein fragment of 360 residues. This fragment is not closely related to any protein in the current PIR database The last exon in the 2.7 kb HindIII fragment is followed by an intron which continues beyond the fragment. The first exon is preceded by a non-coding region which may be part of an intron or the unc-6 promoter region. In fact, a possible 21 residue signal sequence with an initiator methionine occurs in the first exon shortly upstream of the Tc1::rh1035 insertion site. TATA and CCAAT motifs occur about 90 and 120 bp upstream of the proposed initiator codon. The decanucleotide sequence TTTGCCTCTC is tandemly repeated about 200 bp upstream of this codon. [See Figure 1]

Bartolini F et al. (2005) J Cell Sci "Identification of a novel tubulin-destabilizing protein related to the chaperone cofactor E."

Cassimeris L, Tian G, Piehl M, Bartolini F, Cowan NJ, Lewis SA

[J Cell Sci, 2005]

Factors that regulate the microtubule cytoskeleton are critical in determining cell behavior. Here we describe the function of a novel protein that we term E-like based on its sequence similarity to the tubulin-specific chaperone cofactor E. We find that upon overexpression, E-like depolymerizes microtubules by committing tubulin to proteosomal degradation. Our data suggest that this function is direct and is based on the ability of E-like to disrupt the tubulin heterodimer in vitro. Suppression of E-like expression results in an increase in the number of stable microtubules and a tight clustering of endocellular membranes around the microtubule-organizing center, while the properties of dynamic microtubules are unaffected. These observations define E-like as a novel regulator of tubulin stability, and provide a link between tubulin turnover and vesicle transport.

Toth, Marton L. et al. (2009) International Worm Meeting "HSF-1 is an Essential Downstream Mediator of Resveratrol-induced, SIR-2.1-dependent Longevity in C. elegans."

Soti, Csaba, Toth, Marton L., Csermely, Peter, Dancso, Balazs

[International Worm Meeting, 2009]

Major longevity assurance mechanisms include the heat-shock response governed by the heat-shock transcription factor (HSF-1) and the metabolic stress response, exemplified by the Sir2 deacetylase. Sir2, and recently HSF-1 have been implicated in the life-span extending effect of dietary restriction. Resveratrol, a polyphenol from red wine, is a dietary restriction mimetic that induces longevity and displays an impressive therapeutic potential against various degenerative diseases via Sir2. Resveratrol has also been shown to induce the heat-shock response in mammalian cells. In this study, we have asked how the heat-shock response is involved in resveratrol-induced/Sir2-related longevity in C. elegans. We find that resveratrol specifically induces chaperone expression, thermotolerance and longevity depending on both SIR-2.1 and HSF-1. Moreover, we show that SIR-2.1 is a potent activator of HSF-1-dependent thermotolerance. Finally, we identify HSF-1 as an essential downstream effector of resveratrol-induced, SIR-2.1-dependent longevity in C. elegans. Thus, our results demonstrate a direct interaction of metabolic and proteotoxic stress responses in life-span regulation and indicate that the robustness of the heat-shock response may determine the therapeutic response to resveratrol. Marton Toth''s current address: Rutgers, The State University of NJ, Molecular Biology & Biochemistry, Piscataway, NJ.

Han, Suhao et al. (2009) International Worm Meeting "The role of the centrosomes in the control of cell polarity by the Wnt signaling in C. elegans.."

Han, Suhao, Herman, Michael, Huarcaya-Najarro, Elvis

[International Worm Meeting, 2009]

Multicellular organisms contain a diversity of cell types. One of the major mechanisms responsible for the generation of this cellular diversity are asymmetric cell divisions. A successful asymmetric cell division must be oriented to the body axis, which requires the establishment of the cell polarity. In the Caenorhabditis elegans embryo, the centrosomes initiate the establishment of polarity in response to a polarity signal established by the sperm entry point (Cowan and Hyman, 2004). During later embryonic and postembryonic development the polarities of many divisions are controlled by Wnt signaling and the Wnt/PCP pathways, but the role the centrosomes play in these divisions is not clear. Centrosome formation during C. elegans embryonic development requires the function of SPD-5, a coiled-coil protein. In spd-5 mutant embryos, the pericentriolar material (PCM) fails to form, leading to the loss of centrosomes and centrosomal asters, resulting in the loss of embryonic polarity (Hamill et al., 2002). Recently, we discovered that SPD-5 may play a role in the control of postembryonic cell polarities that are also controlled by Wnt signaling. Specifically we found that spd-5(RNAi) causes defects in T and B cell polarities. Using SPD-5 antisera, we observed SPD-5 localization in a pattern consistent with centrosomes in many cells in developing larvae. In addition, we observed SPD-5 localization to the cytoplasm of the seam cells. To further investigate the role of SPD-5 in the control of T cell polarity, we have constructed a gfp::spd-5 fusion protein driven by the SCM (seam cell maker) promoter. Our preliminary results indicate that the localization of the GFP::SPD-5 fusion protein in wild-type animals also consistent with centrosome positions. We are using this GFP::SPD-5 fusion protein as well as genetic experiments to further investigate the molecular and genetic interactions of SPD-5 with Wnt signaling, centrosomal and other cytoskeletal components. References: Cowan, C. R., Hyman, A. A., 2004. Nature. 431, 92-6. Hamill, D. R., et al., 2002. Dev Cell. 3, 673-84.

Tsai MC et al. (2007) J Cell Biol "Microtubules are involved in anterior-posterior axis formation in C. elegans embryos."

Tsai MC, Ahringer J

[J Cell Biol, 2007]

Microtubules deliver positional signals and are required for establishing polarity in many different organisms and cell types. In Caenorhabditis elegans embryos, posterior polarity is induced by an unknown centrosome-dependent signal. Whether microtubules are involved in this signaling process has been the subject of controversy. Although early studies supported such an involvement (O''Connell, K.F., K.N. Maxwell, and J.G. White. 2000. Dev. Biol. 222:55-70; Wallenfang, M.R., and G. Seydoux. 2000. Nature. 408:89-92; Hamill, D.R., A.F. Severson, J.C. Carter, and B. Bowerman. 2002. Dev. Cell. 3:673-684), recent work involving RNA interference knockdown of tubulin led to the conclusion that centrosomes induce polarity independently of microtubules (Cowan, C.R., and A.A. Hyman. 2004. Nature. 431:92-96; Sonneville, R., and P. Gonczy. 2004. Development. 131: 3527-3543). In this study, we investigate the consequences of tubulin knockdown on polarity signaling. We find that tubulin depletion delays polarity induction relative to wild type and that polarity only occurs when a small, late-growing microtubule aster is visible at the centrosome. We also show that the process of a normal meiosis produces a microtubule-dependent polarity signal and that the relative levels of anterior and posterior PAR (partitioning defective) polarity proteins influence the response to polarity signaling. Our results support a role for microtubules in the induction of embryonic polarity in C. elegans.

Jenkins NL et al. (2000) European Worm Meeting "C. elegans and humans share similar patterns of non-linear growth"

Lithgow GJ, Clayton PE, Jenkins NL, Foster P, Gill MS

[European Worm Meeting, 2000]

Human growth is generally considered to be a relatively smooth, continuous process. However when examined frequently over short time periods growth is non-linear, with variations in height occurring at daily, weekly, monthly and annual intervals. This pattern of growth is likely to be dictated by nutritional, environmental, hormonal and genetic influences, but delineation of the relative contribution of each is not practical or ethical in humans. We have therefore sought to establish C. elegans as a model in which to characterise the processes that underpin non-linear growth. We have examined short-term growth by video microscopy in the Bristol N2 strain with size determinations made every 15 minutes over 12 hours in both L1 and L3. Length and area were calculated from triplicate images. Using curve fitting, individual growth curves exhibited periods of rapid growth interspersed by periods of little or no growth, consistent with the non-linear growth observed in human studies. Smoothed empirical growth velocities were calculated as the difference between successive measurements, scaled by the intervening time period. These data suggest that L1 growth can be characterised by 5-7 growth spurts of duration 80-95 min, with velocity ranging from a peak of 0.27-0.34m/min to a nadir of 0.01-0.05m/min. We are particularly interested in trying to relate the pattern of short-term growth to events in the cell lineage. Moreover the apparent conservation of short-term growth patterns between nematodes and humans suggests that C. elegans could be used to uncover novel genes that influence the kinetics of growth in both species. comments: Affiliations: Academic Unit of Child Health (MG, PC), School of Biological Sciences (MG, NJ, GL), Dept of Mathematics (PF).