Best AM et al. (2018) Cell Microbiol "Evasion of phagotrophic predation by protist hosts and innate immunity of metazoan hosts by Legionella pneumophilla."

Best AM, Kwaik YA

[Cell Microbiol, 2018]

Legionella pneumophila is a ubiquitous environmental bacterium that has evolved to infect and proliferate within amoebae and other protists. It is thought that accidental inhalation of contaminated water particles by humans is what has enabled this pathogen to proliferate within alveolar macrophages and cause pneumonia. However, the highly evolved macrophages are equipped more sophisticated innate defense mechanisms than protists, such as the evolution of phagotrophic feeding into phagocytosis with more evolved innate defense processes. Not surprisingly, the majority of proteins involved in phagosome biogenesis (~80%) have origins in the phagotrophy stage of evolution. There are a plethora of highly evolved cellular and innate metazoan processes, not represented in Protist biology, that are modulated by L. pneumophila; including TLR2 signaling, NF-B, apoptotic and inflammatory processes, histone modification, caspases, and the NLRC-Naip5 inflammasomes. Importantly, L. pneumophila infects hemocytes of the invertebrate Galleria mellonella, kill G. mellonella larvae, and proliferate in and kill Drosophila adult flies and Caenorhabditis elegans. Although co-evolution with protist hosts has provided a substantial blueprint for L. pneumophila to infect macrophages, we discuss the further evolutionary aspects of co-evolution of L. pneumophila and its adaptation to modulate various highly evolved innate metazoan processes prior to becoming a human pathogen.

Schierenberg E et al. (1992) Seminars in Developmental Biology "The establishment of embryonic axes and determination of cell fates in embryos of the nematode Caenorhabditis elegans."

Schierenberg E, Strome S

[Seminars in Developmental Biology, 1992]

At the 4-cell stage of the C. elegans embryo, three axes can be defined: anterior-posterior (A-P), dorsal-ventral (D-V), and left-right (L-R). The A-P axis first becomes obvious in the newly fertilized 1-cell embryo. Pronouned cytoplasmic assymmetries arise along the A-P axis during the first cell cycle, after which the zygote undergoes a series of stem cell-like cleavages with an A-P orientation of the mitotic spindle; these cleavages generate several somatic founder cells and a primordial germ cell. The D-V and L-R axes are defined by the direction of spindle rotation as the 2-cell embryo divides into four cells. In contrast to the A-P axis, there do not appear to be cellular asymmetries associated with the D-V and L-R axes, and both axes can easily be reversed by micromanipulation. Thus, with respect to the roles that the embryonic axes serve in cell-fate determination in the early C. elegans embryo, it appears that internally transmitted developmental information is differentially segregated along the A-P axis, but not along the D-V or L-R axes. Instead, D-V and L-R differences in the fates of cells within lineages appear to be dictated by differential

Richie CT et al. (2005) Curr Biol "Chromosome segregation: Aurora B gets Tousled."

Golden A, Richie CT

[Curr Biol, 2005]

Aurora B kinases play important roles during mitosis in eukaryotic cells; new work in Caenorhabditis elegans has identified the Tousled kinase TLK-1 as a substrate activator of the model nematode''''s Aurora B kinase AIR-2 which acts to ensure proper chromosome segregation during

Blackwell TK et al. (2019) Genetics "TOR Signaling in Caenorhabditis elegans Development, Metabolism, and Aging."

Han M, Wu Z, Sewell AK, Blackwell TK

[Genetics, 2019]

The <b>T</b>arget <b>o</b>f <b>R</b>apamycin (TOR or mTOR) is a serine/threonine kinase that regulates growth, development, and behaviors by modulating protein synthesis, autophagy, and multiple other cellular processes in response to changes in nutrients and other cues. Over recent years, TOR has been studied intensively in mammalian cell culture and genetic systems because of its importance in growth, metabolism, cancer, and aging. Through its advantages for unbiased, and high-throughput, genetic and <i>in vivo</i> studies, <i>Caenorhabditis elegans</i> has made major contributions to our understanding of TOR biology. Genetic analyses in the worm have revealed unexpected aspects of TOR functions and regulation, and have the potential to further expand our understanding of how growth and metabolic regulation influence development. In the aging field, <i>C. elegans</i> has played a leading role in revealing the promise of TOR inhibition as a strategy for extending life span, and identifying mechanisms that function upstream and downstream of TOR to influence aging. Here, we review the state of the TOR field in <i>C. elegans</i>, and focus on what we have learned about its functions in development, metabolism, and aging. We discuss knowledge gaps, including the potential pitfalls in translating findings back and forth across organisms, but also describe how TOR is important for <i>C. elegans</i> biology, and how <i>C. elegans</i> work has developed paradigms of great importance for the broader TOR field.

Burns RG et al. (1996) Trends in Cell Biology "Getting to the heart of B-tubulin."

Farrell KW, Burns RG

[Trends in Cell Biology, 1996]

Cellular microtubules assemble and disassemble at a variety of rates and frequencies, and these properties contribute directly to the cell-cycle-associated rearrangements of the microtubule cytoskeleton and to the molecular basis of mitosis. The kinetics of assembly/disassembly are governed, in part, by the hydrolysis of GTP bound to the B-tubulin nucleotide-binding site. The B-tubulin GTP-binding site, therefore, lies at the heart of microtubule assembly-disassembly kinetics, and the elucidation of its structure is central to an understanding of the cellular behaviour of microtubules. Unfortunately, the crystallographic structure of B-tubulin is not yet available. In this review, we describe the progress being made using mutagenesis and biochemical studies to understand the structure of this unusual GTP-binding site.

Pinos D et al. (2021) Microbiol Mol Biol Rev "Response Mechanisms of Invertebrates to Bacillus thuringiensis and Its Pesticidal Proteins."

Ferre J, Hernandez-Martinez P, Andres-Garrido A, Pinos D

[Microbiol Mol Biol Rev, 2021]

SUMMARYExtensive use of chemical insecticides adversely affects both environment and human health. One of the most popular biological pest control alternatives is bioinsecticides based on <i>Bacillus thuringiensis</i> This entomopathogenic bacterium produces different protein types which are toxic to several insect, mite, and nematode species. Currently, insecticidal proteins belonging to the Cry and Vip3 groups are widely used to control insect pests both in formulated sprays and in transgenic crops. However, the benefits of <i>B. thuringiensis</i>-based products are threatened by insect resistance evolution. Numerous studies have highlighted that mutations in genes coding for surrogate receptors are responsible for conferring resistance to <i>B. thuringiensis</i> Nevertheless, other mechanisms may also contribute to the reduction of the effectiveness of <i>B. thuringiensis</i>-based products for managing insect pests and even to the acquisition of resistance. Here, we review the relevant literature reporting how invertebrates (mainly insects and <i>Caenorhabditis elegans</i>) respond to exposure to <i>B. thuringiensis</i> as either whole bacteria, spores, and/or its pesticidal proteins.

Epstein HF (1986) "Differential roles of myosin isoforms in filament assembly."

Epstein HF

[1986]

Wild-type body wall muscle cells of Caenorhabditis elegans produce at a constant ratio two myosin heavy chain isoforms, A and B, that form homodimeric myosins. Electron microscopy of negatively stained complexes of isoform-specific antibodies with isolated thick filaments shows that the surface of the 9.7 =B5m long filament is differentiated with respect to myosin content: a medial 1.8 =B5m zone contains myosin A and two polar 4.4 = =B5m zones contain myosin B. Biochemical and electron microscopic studies show that at 0.45 M KC1, pH 6.35, myosin B and paramyosin are solubilized. The medial all-myosin A region with novel core structures extending in a polar manner remain. These dissociation experiments suggest a sequential model for wild-type thick filament assembly in which myosins A and B would participate in the initiation and termination of assembly, respectively. Analysis of mutant thick filaments clarifies the relationship of the myosin isoforms. CB190 (unc-54 I) thick filaments contain myosin A only and have normal length. CB1214 (unc-15 I) mutants produce no paramyosin, and their thick filaments are composed of a medial myosin region

Caffrey CR et al. (2018) PLoS Negl Trop Dis "Cysteine proteases as digestive enzymes in parasitic helminths."

Caffrey CR, Smith D, Dalton JP, Rebello KM, Goupil L

[PLoS Negl Trop Dis, 2018]

We briefly review cysteine proteases (orthologs of mammalian cathepsins B, L, F, and C) that are expressed in flatworm and nematode parasites. Emphasis is placed on enzyme activities that have been functionally characterized, are associated with the parasite gut, and putatively contribute to degrading host proteins to absorbable nutrients [1-4]. Often, gut proteases are expressed as multigene families, as is the case with Fasciola [5] and Haemonchus [6], presumably expanding the range of substrates that can be degraded, not least during parasite migration through host tissues [5]. The application of the free-living planarian and Caenorhabditis elegans as investigative models for parasite cysteine proteases is discussed. Finally, because of their central nutritive contribution, targeting the component gut proteases with small-molecule chemical inhibitors and understanding their utility as vaccine candidates are active areas of research [7].

Barnes TM (1994) Trends in Genetics "OPUS-A growing family of gap junction proteins?"

Barnes TM

[Trends in Genetics, 1994]

Recently, Krishnan et al. Reported the cloning and sequencing of the Drosophila shaking-B (shakB; alias Passover, or Pas) gene, required for the jump response to an optical stimulus. The predicted gene product was similar to those of both the Drosophila gene lethal (1) optic ganglion reduced [l(1)ogre] and the Caenorhabditis elegans gene unc-7, which together define a new family of evolutionarily conserved proteins that may be membrane-associated. Below I describe three additional members of this family, as identified by sequence homologies. An alignment of all these sequences permits a more informed prediction of the general structure of members of this family. The structure is that of a new type of multipass transmembrane protein. On the basis of the phenotypes of mutant organisms, I suggest that the encoded proteins may be members of a family of invertebrate

Lv Z et al. (2015) Parasitol Res "Genome mining offers a new starting point for parasitology research."

Wu Z, Ji P, Li H, Cai Y, Zhang L, Luo S, Wang H, Lv Z

[Parasitol Res, 2015]

Parasites including helminthes, protozoa, and medical arthropod vectors are a major cause of global infectious diseases, affecting one-sixth of the world's population, which are responsible for enormous levels of morbidity and mortality important and remain impediments to economic development especially in tropical countries. Prevalent drug resistance, lack of highly effective and practical vaccines, as well as specific and sensitive diagnostic markers are proving to be challenging problems in parasitic disease control in most parts of the world. The impressive progress recently made in genome-wide analysis of parasites of medical importance, including trematodes of Clonorchis sinensis, Opisthorchis viverrini, Schistosoma haematobium, S. japonicum, and S. mansoni; nematodes of Brugia malayi, Loa loa, Necator americanus, Trichinella spiralis, and Trichuris suis; cestodes of Echinococcus granulosus, E. multilocularis, and Taenia solium; protozoa of Babesia bovis, B. microti, Cryptosporidium hominis, Eimeria falciformis, E. histolytica, Giardia intestinalis, Leishmania braziliensis, L. donovani, L. major, Plasmodium falciparum, P. vivax, Trichomonas vaginalis, Trypanosoma brucei and T. cruzi; and medical arthropod vectors of Aedes aegypti, Anopheles darlingi, A. sinensis, and Culex quinquefasciatus, have been systematically covered in this review for a comprehensive understanding of the genetic information contained in nuclear, mitochondrial, kinetoplast, plastid, or endosymbiotic bacterial genomes of parasites, further valuable insight into parasite-host interactions and development of promising novel drug and vaccine candidates and preferable diagnostic tools, thereby underpinning the prevention and control of parasitic diseases.