lin-36, a Class B Synthetic Multivulva Gene, Encodes a Novel Protein Jeffrey H. Thomas and H. Robert Horvitz, HHMI, Dept. Biology, MIT, Cambridge, MA 02139, USA
It is an honor and a great pleasure to introduce Dr. Robert Horvitz to you as the 1998 recipient of the Alfred Sloan Prize of the General Motors Cancer Research Foundation. Let me begin by telling you a little bit about Bob's
THE C. ELEGANS CLEAVAGE AND POLYADENYLATION SlGNAL Tom Blumenthal, Department of Biology, Indiana University. Bloomington, IN 47405; Owen White and Chris Fields, Institute For Genomic Research, Gaithersburg, MD, 20878
The growth promoting activity of protein-haemin co-precipitates from ferritin, apoferritin, transferrin, bovine serum albumin, conalbumin and egg white on maturation and reproduction of C. briggsae has been evaluated. Ferritin, apoferritin and transferrin were found to be biologically highly active in the presence of haemin. Bovine serum albumin, conalbumin and egg white were slightly active. Maturation and reproduction of C. briggsae on the coagulates from bovine serum albumin and egg white were nearly independent of the dose administered, probably because the limited availability of haemin from these coagulates permits but slow growth, even in the presence of abundant proteinaceous material. Bovine serum albumin, egg white and conalbumin failed to support continuous growth of C. briggsae. It is supposed that the limited availability of haemin from these coagulates inhibits normal maturation and reproduction of the F1 progeny. These experiments clearly demonstrate the requirement for particulate haem. The requirement for
For everyone who deals with the characterization of expression patterns in the nervous system, the truly impressive paper of White et al., 1986 ("Mind of the Worm") serves as the ultimate source of knowledge. While the largely invariant neural cell body positions described by Sulston et al. are an essential tool in the identification of neurons, the axon morphologies described by White et al. greatly facilitate the identification of a given neuron.
A variety of specimens including bacteria, ciliates, choanoflagellates (Salpingoeca rosetta), zebrafish (Danio rerio) embryos, nematode worms (Caenorhabditis elegans), and leaves of white clover (Trifolium repens) plants were high pressure frozen, freeze-substituted, infiltrated with either Epon, Epon-Araldite, or LR White resins, and polymerized. Total processing time from freezing to blocks ready to section was about 6 h. For epoxy embedding the specimens were freeze-substituted in 1% osmium tetroxide plus 0.1% uranyl acetate in acetone. For embedding in LR White the freeze-substitution medium was 0.2% uranyl acetate in acetone. Rapid infiltration was achieved by centrifugation through increasing concentrations of resin followed by polymerization at 100C for 1.5-2 h. The preservation of ultrastructure was comparable to standard freeze substitution and resin embedding methods that take days to complete. On-section immunolabeling results for actin and tubulin molecules were positive with very low background labeling. The LR White methods offer a safer, quicker, and less-expensive alternative to Lowicryl embedding of specimens processed for on-section immunolabeling without traditional aldehyde fixatives.
The original version of this article [1] unfortunately contained a mistake. The author list contained a spelling error for the author Hannah V. McCue. The original article has been corrected for this error. The corrected author list is given below:Xi Chen, Hannah V. McCue, Shi Quan Wong, Sudhanva S. Kashyap, Brian C. Kraemer, Jeff W. Barclay, Robert D. Burgoyne and Alan Morgan
J Environ Sci Health A Tox Hazard Subst Environ Eng,
2017]
This study aimed to investigate the biological impact of exposure on domestic light emitting diodes (LED) lighting using the free-living nematode Caenorhabditis elegans as a model. Nematodes were separately exposed to white LED light covering the range of 380-750nm, blue light at 450nm and black light at 380-420nm for one life cycle (egg to adult) with dark exposure as the control. Each light range induced stress to the nematode C. elegans such as reducing the number of the hatched eggs and/or delayed the maturation of the hatched eggs to the adult stage. In addition, it lowered or prevented the ability of adults to lay eggs and impaired the locomotion in the exposed worms. The observed type of biological stress was also associated with the production of reactive oxygen species (ROS) as compared to nematodes grown in the dark. It is concluded that the blue light component of white LED light may cause health problems, and further investigation is required to test commercial brands of white LEDs that emit different amounts of blue light.
For the first time, scientists have the nearly complete genetic instructions for an animal that, like humans, has a nervous system, digests food, and reproduces sexually. The 97-million-base genome of the tiny roundworm Caenorhabditis elegans was deciphered by an international team led by Robert Waterston and John Sulston. The work was reported in a special issue of the journal Science (December 11, 1998) that featured six articles describing the history and significance of the accomplishment and some early sequence-analysis results.