Dishevelled controls apical docking and planar polarization of basal bodies in ciliated epithelial cells

The planar cell polarity (PCP) signaling system governs many aspects of polarized cell behavior. Here, we use an in vivo model of vertebrate mucociliary epithelial development to show that Dishevelled (Dvl) is essential for the apical positioning of basal bodies. We find that Dvl and Inturned mediate the activation of the Rho GTPase specifically at basal bodies, and that these three proteins together mediate the docking of basal bodies to the apical plasma membrane. Moreover, we find that this docking involves a Dvl-dependent association of basal bodies with membrane-bound vesicles and the vesicle-trafficking protein, Sec8. Once docked, basal bodies again require Dvl and Rho for the planar polarization that underlies directional beating of cilia. These results demonstrate previously undescribed functions for PCP signaling components and suggest that a common signaling apparatus governs both apical docking and planar polarization of basal bodies.     

Dermatologically active sesquiterpene lactones in trichomes ofParthenium hysterophorus L. (Compositae)

Summary Scanning electron microscopy of the leaf surface, phyllaries and achene-complex ofParthenium hysterophorus L. showed the presence of 4 types of glandular and non-glandular trichomes. Chemical analysis established the presence of sesquiterpene lactones in the trichomes that cause eczematous dermatitis.Acknowledgments. We thank Dr.Garry Cole, University of Texas, for the use of the AMR-1000 Scanning electron microscope andJudy Stevenson for technical assistance. The work at the University of Texas was supported by the National Science Foundation (Grant No. BMS 71-01088) and the Robert A. Welch Foundation (Grant No. F-130).     

The behavioral effects of 2,5-dimethoxy-4-alkyl amphetamines

Cellular and Molecular Life Sciences - Le comportement des rats a été fortement influencé par des dérivés de la 2,5-diméthoxyamphétamine Le mécanisme...     

Response ofHeliothis virescens to pheromonal components and an inhibitor in olfactometers

Summary Laboratory-reared males ofHeliothis virescens (F.) that were released in olfactometers in the laboratory were attracted to theH. virescens synthetic pheromone, but not to (Z)-9-tetradecen-1-ol formate (Z-9-TDF), or to either pheromonal component, (Z)-11-hexadecenal (Z-11-HDAL) or (Z)-9-tetradecenal (Z-9-TDAL). Also, they did not respond to the pheromone when it was dispersed simultaneously with Z-9-TDF. The proximity of the test chemicals in the olfactometer made little, if any, difference in the response ofH. virescens males to the pheromone source. Preexposure to the synthetic pheromone, Z-9-TDF, Z-11-HDAL, or Z-9-TDAL greatly reduced the number ofH. virescens males responding to the pheromone. This reduction was probably caused by habituation of the moths to these chemicals.The authors wish to thank A. H. Baumhover, E. Hart and other personnel of the Tobacco Research Laboratory, Oxford, N. C., for supplying many of the insects used in these studies.     

Odorous urine following asparagus ingestion in man

The production of odorous urine after the ingestion of asparagus has been shown to occur in 43% of 800 volunteers investigated. This characteristic is reproducible over a 12-month-period and has been shown to remain with individuals for virtually a lifetime. Family studies suggest that the ability to produce the odorous urine is inherited as an autosomal dominant trait.     

Regulation of immunity by self-reactive T cells

A basic principle of immunology is that lymphocytes respond to foreign antigens but tolerate self tissues. For developing T cells, the ability to distinguish self from non-self is acquired in the thymus, where the majority of self-reactive cells are eliminated. Recently, however, it has become apparent that some self-reactive T cells avoid being destroyed and instead differentiate into specialized regulatory cells. This appears to be beneficial. Subpopulations of self-reactive T cells have a strong influence on self tolerance and may represent targets for therapeutic intervention to control a variety of autoimmune diseases, tumour growth and infection.