Smith ST et al. (1996) Development "A conserved region of engrailed, shared among all en-, gsc-, Nk1-, Nk2- and msh-class homeoproteins, mediates active transcriptional repression in vivo."

Smith ST, Jaynes JB

[Development, 1996]

The engrailed homeoprotein is a dominantly acting or ''active'' transcriptional repressor both in cultured cells and in vivo. When retargeted via a homeodomain swap to the endogenous fushi tarazu gene (ftz), it actively represses it, resulting in a ftz mutant phenocopy. We have mapped functional regions of engrailed using this in vivo repression assay. In addition to a region containing an active repression domain identified in cell culture assays (K. Han and J. L. Manley (1993) EMBO J. 12, 2723-2733), we find that two evolutionarily conserved regions contribute to activity. The one of these that does not flank the HD is particularly crucial to repression activity in vivo. We find that this domain is present not only in all engrailed-class homeoproteins but also in all known members of several other classes, including goosecoid, Nk1, Nk2 and msh. Thus engrailed''s active repression function in vivo is dependent on a highly conserved interaction that was established early in the evolution of the homeobox gene superfamily. We further show using rescue transgenes that the widely conserved in vivo repression domain is required for the normal function of engrailed in the embryo.

Smith, Ewan St. John et al. (2013) International Worm Meeting "Chemical tuning of CO2-responsive BAG neurons."

Ringstad, Niels, Smith, Ewan St. John, Martinez-Velazquez, Luis Antonio

[International Worm Meeting, 2013]

Animals from diverse phyla possess neurons that are activated by the product of aerobic respiration, carbon dioxide (CO2). It has long been thought that such neurons primarily detect the products of CO2 hydration, protons and bicarbonate. To identify the specific chemical cue that activates BAG neurons, we studied isolated BAG neurons in culture, using methods that allow both monitoring of cell physiology and control of the extracellular and intracellular environments. We show that the majority of isolated BAG neurons showed calcium responses to molecular CO2, although a fraction of these cells can also be activated by acid stimuli. These responses to acid stimuli were not seen when the BAG neurons were tested in situ. One component of the BAG transduction pathway, the receptor-type guanylate cyclase GCY-9, suffices to confer cellular sensitivity to both CO2 and acid, indicating that it is a bifunctional chemoreceptor. We speculate that in other animals, receptors similarly capable of detecting molecular CO2 might mediate effects of CO2 on neural circuits and behavior.

Hu KJ et al. (1999) Nematology "Nematicidal metabolites produced by Photorhabdus luminescens (Enterobacteriaceae), bacterial symbiont of entomopathogenic nematodes."

Hu KJ, Li JX, Webster JM

[Nematology, 1999]

The secondary metabolites, 3,5-dihydroxy-4-isopropylstilbene (ST) and indole, from the culture filtrate of Photorhabdus luminescens MD, were shown to have nematicidal properties. ST caused nearly 100% mortality of 54 and adults of Aphelenchoides rhytium, Bursaphelenchus spp. and Caenorhabditis elegans at 100 mu g/ml, but had no effect on J2 of Meloidogyne incognita or infective juveniles (IJ) of Heterorhabditis megidis at 200 mu g/ml. Indole was lethal to several nematode species at 300 mu g/ml, and caused a high percentage of Bursaphelenchus spp. (54 and adults), M, incognita (J2) and Heterorhabditis spp. (IJ) to be paralysed at 300, 100 and 400 mu g/ml, respectively. Both ST and indole inhibited egg hatch of M, incognita. ST repelled IJ of some Steinernema spp. but not IJ of Heterorhabditis spp., and indole repelled IJ of some species of both Steinernema and Heterorhabditis. ST, but not indole, was produced in nematode-infected larval Galleria mellonella. after 24 h infection.

Hresko MC et al. (1994) Worm Breeder's Gazette "Shoot First, Ask Questions Later"

Shrimankar PV, Hresko MC, Waterston RH

[Worm Breeder's Gazette, 1994]

Shoot First, Ask Questions Later M.C Hresko, P.V. Shrimankar and R.H. Waterston. Washington Univ. Sch. of Med., St. Louis, MO 63110. coutu@sequencer.wustl.edu and pvs@elegans.wustl.edu

McCarter JP et al. (1994) Worm Breeder's Gazette "Somatic Regulation of Germ-line Development. Introduction and Part I; Mitotic Proliferation"

Schedl TB, McCarter JP

[Worm Breeder's Gazette, 1994]

Somatic Regulation of Germ-line Development Introduction, and Part I; Mitotic Proliferation Jim McCarter and Tim Schedl. Dept. of Genetics, Washington Univ. School of Medicine, St. Louis, MO 63110, jim@wugenmail.wustl.edu

Consortium TCeGS (1994) Worm Breeder's Gazette "The C. elegans Genome Sequencing Project: A Progress Report."

Consortium TCeGS

[Worm Breeder's Gazette, 1994]

The C. elegans genome sequencing project: A progress report. The C. elegans Genome Consortium, Genome Sequencing Center, Washington University School of Medicine, St. Louis, Missouri, USA and Sanger Centre, Hinxton Hall, Cambridge, UK.

Consortium TCeGS (1994) Worm Breeder's Gazette "The C. elegans Genome Sequencing Project: A Progress Report"

Consortium TCeGS

[Worm Breeder's Gazette, 1994]

The C. elegans genome sequencing project: A progress report. The C. elegans Genome Consortium, Genome Sequencing Center, Washington University School of Medicine, St. Louis, Missouri, USA and Sanger Centre, Hinxton Hall, Cambridge, UK.

Li WQ et al. (1992) Worm Breeder's Gazette "Characterization of the Axonal Guidance and Outgrowth gene Unc-33"

Shaw JE, Li WQ, Herman RK

[Worm Breeder's Gazette, 1992]

Characterization of the axonal guidance and outgrowth gene unc-33 W. Li, R. K. Herman and J. E. Shaw Department of Genetics and Cell biology, University of Minnesota, St Paul, MN 55108

Verma S et al. (2015) IUBMB Life "Understanding the complexities of Salmonella-host crosstalk as revealed by in vivo model organisms."

Srikanth CV, Verma S

[IUBMB Life, 2015]

Foodborne infections caused by non-typhoidal Salmonellae, such as Salmonella enterica serovar Typhimurium (ST), pose a major challenge in the developed and developing world. With constant rise of drug-resistant strains, understanding the epidemiology, microbiology, pathogenesis and host-pathogen interactions biology is a mandatory requirement to enable health systems to be ready to combat these illnesses. Patient data from hospitals, at least from some parts of the world, have aided in epidemiological understanding of ST-mediated disease. Most of the other aspects connected to Salmonella-host crosstalk have come from model systems that offer convenience, genetic tractability and low maintenance costs that make them extremely valuable tools. Complex model systems such as the bovine model have helped in understanding key virulence factors needed for infection. Simple systems such as fruit flies and Caenorhabditis elegans have aided in identification of novel virulence factors, host pathways and mechanistic details of interactions. Some of the path-breaking concepts of the field have come from mice model of ST colitis, which allows genetic manipulations as well as high degree of similarity to human counterpart. Together, they are invaluable for correlating in vitro findings of ST-induced disease progression in vivo. The current review is a compilation of various advances of ST-host interactions at cellular and molecular levels that has come from investigations involving model organisms.

Broverman SA et al. (1992) Worm Breeder's Gazette "Transformation Rescue of him-8"

Meneely PM, Broverman SA

[Worm Breeder's Gazette, 1992]

1) him-8, him-5 and him-1 asymmetrically affect recombination (pairing?) of the X chromosome. - 2) Transformation rescue of him-8. Sherryl Broverman and Philip Meneely, FHCRC, 1124 Columbia St., Seattle WA 98104, (206) 667-4523i FAX 206 667 4737