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Biol Bull,
1998]
The identification of the molecular components of the developmental neurogenic programs in different organisms has revealed an astounding degree of conservation across phylogeny, suggesting that the basic mechanisms of neural development have also been conserved in evolution. One class of conserved neural regulatory genes, the LIM homeobox genes, encode transcription factors with two Zn-finger-like LIM domains and a DNA-binding homeodomain. Vertebrate members of this class have been implicated in neurogenesis by correlative expression evidence: e.g., the combinatorial expression of LIM homeobox genes in the vertebrate spinal cord suggested a "LIM-code" for specific motorneuronal targeting choices. Genetic analysis in Drosophila also demonstrated their essential role in axon pathfinding and the determination of neurotransmitter identity. The genome of the nematode Caenorhabditis elegans is almost completely sequenced, thus allowing the analysis of complete gene families in a metazoan organism. C. elegans contains seven LIM homeobox genes. Almost all C. elegans LIM homeobox genes fall into subclasses that are defined by the presence of similar genes from arthropods and vertebrates, suggesting a common origin for different subclasses of LIM homeobox genes.
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Trends Genet,
2000]
Homeobox genes play fundamental roles in development. They can be subdivided into several subfamilies, one of which is the LIM-homeobox subfamily. The primary structure of LIM-homeobox genes has been remarkably conserved through evolution. Have their functions similarly been conserved? A host of new data has been derived from mutational analysis in diverse organisms, such as nematodes, flies and vertebrates. These studies have revealed a prominent involvement of LIM-homeodomain proteins in tissue patterning and differentiation, and their function in neural patterning is evident in all organisms studied to date. Here, we summarize the recent findings on LIM-homeobox gene function, compare the function of these genes from different organisms and describe specific co-factor requirements.
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Curr Biol,
2003]
Recent studies highlight the striking similarity between vertebrate focal adhesion plaques and Caenorhabditis elegans muscle adhesion structures and position LIM domain proteins as central players at focal adhesions.
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Exp Gerontol,
2006]
Caenorhabditis elegans has been used to model aspects of a number of age-associated neurodegenerative diseases, including Alzheimer''s, Parkinson''s and Huntington''s diseases. These models have typically involved the transgenic expression of disease-associated human proteins. Here I describe my laboratory''s specific experience engineering C. elegans models of Alzheimer''s disease, and give a general consideration of the advantages and disadvantages of these C. elegans models. The type of insights that might be gained from using these (relatively) simple models are highlighted. In particular, I consider the potential these models have for uncovering common and unique fundamental toxic mechanisms underlying human neurodegenerative diseases.
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Curr Biol,
2001]
When meiotic cells complete S phase, homologous chromosomes pair, synapse and undergo recombination. A checkpoint protein is somehow required for meiotic chromosome pairing in C. elegans, thus providing a direct link between S phase and the rest of the meiotic program.
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Toxins (Basel),
2016]
Staphylococcus aureus is an opportunistic pathogen and the leading cause of a wide range of severe clinical infections. The range of diseases reflects the diversity of virulence factors produced by this pathogen. To establish an infection in the host, S. aureus expresses an inclusive set of virulence factors such as toxins, enzymes, adhesins, and other surface proteins that allow the pathogen to survive under extreme conditions and are essential for the bacteria's ability to spread through tissues. Expression and secretion of this array of toxins and enzymes are tightly controlled by a number of regulatory systems. S. aureus is also notorious for its ability to resist the arsenal of currently available antibiotics and dissemination of various multidrug-resistant S. aureus clones limits therapeutic options for a S. aureus infection. Recently, the development of anti-virulence therapeutics that neutralize S. aureus toxins or block the pathways that regulate toxin production has shown potential in thwarting the bacteria's acquisition of antibiotic resistance. In this review, we provide insights into the regulation of S. aureus toxin production and potential anti-virulence strategies that target S. aureus toxins.
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WormBook,
2007]
Because of their free-living life cycle alternatives, Strongyloides and related nematode parasites may represent the best models for translating C. elegans science to the study of nematode parasitism. S. stercoralis, a significant pathogen of humans, can be maintained in laboratory dogs and gerbils. Biosafety precautions necessary for work with S. stercoralis, though unfamiliar to many C. elegans researchers, are straightforward and easily accomplished. Although specialized methods are necessary for large-scale culture of the free-living stages of S. stercoralis, small-scale cultures for experimental purposes may be undertaken using minor modifications of standard C. elegans methods. Similarly, the morphological similarities between C. elegans and the free-living stages of S. stercoralis allow investigational methods such as laser cell ablation and DNA transformation by gonadal microinjection to be easily adapted from C. elegans to S. stercoralis. Comparative studies employing these methods have yielded new insights into the neuronal control of the infective process in parasites and its similarity to regulation of dauer development in C. elegans. Furthermore, we have developed a practical method for transient transformation of S. stercoralis with vector constructs having various tissue- and cell-specific expression patterns and have assembled these into a modular vector kit for distribution to the community.
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Ann Pharm Fr,
2006]
The Nematode Caenorhabditis elegans (C. elegans) is an established model increasingly used for studying human disease pathogenesis. C. elegans models are based on the mutagenesis of human disease genes conserved in this Nematode or on the transgenesis with disease genes not conserved in C. elegans. Genetic examinations will give new insights on the cellular and molecular mechanisms that are altered in some neurodegenerative diseases like Duchenne''s muscular dystrophy, Huntington''s disease and Alzheimer''s disease. C. elegans may be used for primary screening of new compounds that may be used as drugs in these diseases.
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Mol Cell,
2004]
Applying a combination of innovative approaches to understanding neuronal gene regulation in C. elegans, an article in the latest Developmental Cell (Wenick and Hobert, 2004) gives hope that reading the genome''s transcriptional regulatory code may one day be possible.
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Front Biosci,
2004]
Alzheimer''s disease (AD) is affecting more people every year due to the increase in elderly population. This disease is characterized by senior plaques, containing aggregated amyloid beta peptide (A beta), and neurofibrillary tangles in the AD brains. The A beta depositions are thought to increase in cellular oxidative stress, which subsequently produces neuronal cell death in the patient s brain, causing loss of memory and, in the latter stages, dementia. Diverse models have been established to test this, "Amyloid Toxicity Hypothesis of AD". Among these, the use of the nematode Caenorhabditis elegans has some advantages. This invertebrate has its entire genome known, as well as numerous gene homologues to those seen in humans. In relationship with the cell model, the nematode gives the benefit of an organismal view of the disease. The nematode''s short life span proves useful, when compared with that of mice, allowing mechanistic studies of the disease and pharmacological treatments. Alongside with other laboratories, we have used this in vivo model to correlate the Abeta expression with its toxicity through the observance of the organism''s behavior to provide a better understanding of the cellular processes underlining AD.