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The New York Times,
1997]
His tall figure bent over a computer screen in his laboratory at the Massachusetts General Hospital, Dr. Gary Ruvkun rummages through a distant genetic data base for matches to a gene he believes is involved in diabetes. ?You learn how to read these as they are ratcheting by,? he says, while lines of data streak up his screen. ?I think MTV is good training.?
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Am J Hum Genet,
1998]
Since Sydney Brenner wrote this statement in a visionary research proposal addressed to Max Perutz 35 years ago, an enormous amount of information has been gathered on the biology of the nematode Caenorhabditis elegans ("the worm"), both fulfilling his predictions and exceeding his original expectations. Researchers have identified every cell in the worm and have described all the lineages by which these cells are formed...
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Cells,
2018]
Theodor Boveri is considered as the "father" of centrosome biology. Boveri's fundamental findings have laid the groundwork for decades of research on centrosomes. Here, we briefly review his early work on centrosomes and his first description of the centriole. Mainly focusing on centriole structure, duplication, and centriole assembly factors in <i>C. elegans</i>, we will highlight the role of this model in studying germ line centrosomes in nematodes. Last but not least, we will point to future directions of the <i>C. elegans</i> centrosome field.
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Semin Cell Dev Biol,
2014]
The ability to generate behavioral plasticity according to ever-changing physiological demands and environmental conditions is a universal feature of decision-making circuits in all animals. Decision-making requires complex integration of internal states with sensory context. As a mate searching strategy, the Caenorhabditis elegans male modifies his exploratory behavior in relation to a source of food according to recent sensory experience with mates. Information about the reproductive and nutritional status of the male is also incorporated in his choice of exploratory behavior. The study of mate searching in the C. elegans male, a genetic model organism with a nervous system of only 383 neurons, provides the opportunity to elucidate the molecular and cellular mechanisms of state-dependent control of behavior and sensory integration. Here I review our progress in understanding the physiological and environmental regulation of the male's exploratory choices - to explore in search of mates or to exploit a source of food - and the neural circuits and neuromodulator pathways underlying this decision.
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Chembiochem,
2003]
I never expected to spend most of my life studying worms. However, when the time came for me to choose an area for my postdoctoral research, I was intrigued both with the problems of neurobiology and with the approaches of genetics. Having heard that a new "genetic organism" with a remarkably simple nervous system was being explored by Sydney Brenner - the microscopic soil nematode Caenorhabditis elegans - I decided to join Sydney in his efforts.
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Nat Rev Genet,
2002]
The nematode Caenorhabditis elegans was chosen as a model genetic organism because its attributes, chiefly its hermaphroditic lifestyle and rapid generation time, make it suitable for the isolation and characterization of genetic mutants. The most important challenge for the geneticist is to design a genetic screen that will identify mutations that specifically disrupt the biological process of interest. Since 1974, when Sydney Brenner published his pioneering genetic screen, researchers have developed increasingly powerful methods for identifying genes and genetic pathways in C. elegans.
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Semin Cell Dev Biol,
2014]
Intromission of a male's copulatory organ into his mate's genital orifice is a behavioral step that is conserved in most terrestrial mating behaviors. The behavior serves to anchor the male to his mate and aids in the transmission of the male's gametes into the female. In all animals, the successful execution of intromission likely involves coordinated sensory/motor regulation coupled with constant self-monitoring. The compact male C. elegans reproductive nervous system provides an accessible experimental model for identification and dissection of the molecular and cellular circuit components that promote different motor outputs required for the transfer of the male's genetic material into the self-fertilizing hermaphrodite. The C. elegans male tail contains forty-one sex-specific muscles and 81 sex-specific neurons, which promote different steps of mating behavior. In this review, I will outline the functional contributions of the male-specific sensory-motor neurons and their postsynaptic muscles that control the motions of the male copulatory spicules during the various phases of intromission behavior and ejaculation. In addition, I will summarize the roles of neurotransmitter receptors and ion channels that regulate the outputs of individual circuit components and describe how the intromission circuit uses these molecules to regulate reproductive behavior during male aging and nutritional deprivation.
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Trends Genet,
1997]
Focused studies on model organisms with favorable features have been important for advancing many areas of biology. Nematodes have been a successful model for analyzing development. Can they also be used to study evolution? Paul Sternberg and his present and former colleagues are attempting to answer this question by studying variation of that well-described little structure, the nematode vulva. Their efforts have been well rewarded. Two recent publications extend a series of papers showing a surprising degree of evolutionary variability in vulval development among species. Could it be that comparison of nematode species will prove to be as powerful for penetrating the intimate mechanisms of evolutionary change as analysis of mutant nematodes has been to understanding mechanisms of development?
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Journal of Helminthology,
1955]
Osche (1952) has recently published a sorely needed, comprehensive revision of the genus Rhabditis Dujardin [1844] (sensu lato) including detailed study of certain features of the cephalic end, especially of the stoma or mouth cavity. For some time to come his study will surely be the point of departure for morpholigical and systematic work on the group. On the basis principally of the structure of the metastom (a subdivision of the stoma) and of the esophagus, he recognizes some eight subgenera in the genus Rhabditis, which are as follows: Rhabditis Dujardin [1844] (sensu stricto), Choriorhabditis Osche, 1952, Telorhabditis Osche, 1952, Caenorhabditis Osche, 1952, Mesorhabditis Osche, 1952, Teratorhabditis Oshce, 1952, Protorhabditis Osche, 1952, and Parasitorhabditis Fuch, 1937. For all of these save the last he lists the species recognized by him. For a revision of Parasitorhabditis he refers to an unpublished manuscript by Ruhm.....
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Cell,
2001]
Formation of the three primary germ layers, ectoderm, mesoderm, and endoderm, is an early distinction between groups of cells in developing embryos. Our understanding of their generation in vertebrates has benefitted from the classical experiments of Nieuwkoop and his colleagues (referenced in Nieuwkoop, 1997), in which explants of tissue from the animal hemisphere of amphibian embryos (fated to form ectoderm) apposed to explants of vegetal tissue (fated to form endoderm) were induced to form mesoderm. These results have been widely interpreted as indicating that mesoderm forms at the interface between presumptive endoderm and presumptive ectoderm as a consequence of inductive signals from the former to the latter. However, recent data from nematodes and zebrafish suggest that endoderm and some portion of the mesoderm may derive from a bipotential layer of cells, called the mesendoderm. In addition, the genes involved in this process may be conserved.