BACKGROUND LIN-12/Notch signaling is important for cell-cell interactions during development, and mutations resulting in constitutive LIN-12/Notch signaling can cause cancer. Loss of negative regulators of lin-12/Notch activity has the potential for influencing cell fate decisions during development and the genesis or aggressiveness of cancer. METHODOLOGY/PRINCIPAL FINDINGS We describe two ne...

BACKGROUND Generation of asymmetry in the one-cell embryo of C. elegans establishes the anterior--posterior axis (A-P), and is necessary for the proper identity of early blastomeres. Conserved PAR proteins are asymmetrically distributed and are required for the generation of this early asymmetry. The small G protein Cdc42 is a key regulator of polarity in other systems, and recently it has been...

Of 222 Vibrio cholerae isolates from diverse clinical and environmental sources, 219 produced visible growth in alkaline peptone broth when incubated overnight at 42 degrees C. In field trials conducted to compare enrichment at incubation temperatures of 42 and 35 degrees C, significantly higher rates of isolation (P less than 0.05) and recovery (P less than 0.01) of V. cholerae from oysters we...

In this study, the function of the NAD(P)H dehydrogenase (NDH)-dependent pathway in suppressing the accumulation of reactive oxygen species in chloroplasts was investigated. Hydrogen peroxide accumulated in the leaves of tobacco (Nicotiana tabacum) defective in ndhC-ndhK-ndhJ (DeltandhCKJ) at 42 degrees C and 4 degrees C, and in that of wild-type leaves at 4 degrees C. The maximum quantum effic...

BACKGROUND Biological timing mechanisms that integrate cyclical and successive processes are not well understood. C. elegans molting cycles involve rhythmic cellular and animal behaviors linked to the periodic reconstruction of cuticles. Molts are coordinated with successive transitions in the temporal fates of epidermal blast cells, which are programmed by genes in the heterochronic regulatory...

Genes that specify cell fate can influence multiple aspects of neuronal differentiation, including axon guidance, target selection and synapse formation. Mutations in the unc-42 gene disrupt axon guidance along the C. elegans ventral nerve cord and cause distinct functional defects in sensory-locomotory neural circuits. Here we show that unc-42 encodes a novel homeodomain protein that specifies...

We tested whether resistance of lymphocytes to heat stress is modified by breed, intracellular glutathione content, and extracellular antioxidants. In the first experiment, lymphocytes from Angus (Bos taurus, non-heat-tolerant), Brahman (B. indicus, heat-tolerant), and Senepol (B. taurus, heat-tolerant) heifers (12 heifers per breed) were cultured at 45 degrees C for 3 h to evaluate thermal kil...