Ultrastructure of the Z-organ and associated apophyses in Xiphinema coxi coxi was studied by transmission electron microscopy to determine their structural origin and relationship with other parts of the genital tract. The Z-organ of X. coxi coxi is oval-shaped, ca. 30 microm long and 16 microm wide. It is clearly distinguished from the other parts of the female genital tract by its thick muscu...

Ultrafiltration experiments with laryngotracheitis virus were. first reported by Beach (1930), Gibbs (1931) and Beach (1931). These investigators used the porcelain filters of Berkefeld and the fibrous filters of Seitz and agreed that the virus particles passed readily through the Berkefeld V filters, occasionally through the Berkefeld N filters, and were completely retained by the Berkefeld W ...

Glutamate receptors are ligand-gated ion channels that mediate fast excitatory synaptic transmission throughout the central nervous system. Functional receptors are homo- or heteromeric tetramers with each subunit contributing a re-entrant pore loop that dips into the membrane from the cytoplasmic side. The pore loops form a narrow constriction near their apex with a wide vestibule toward the c...

JCB • VOLUME 167 • NUMBER 6 • 2004 994 Opening closed pores closed mitosis may be less closed than was thought, based on results from Colin De Souza, Stephen Osmani, and colleagues (The Ohio State University, Columbus, OH). The authors find that a fungus opens nuclear pores during mitosis to permit diffusion into and out of the nucleus. Simple organisms may thus be viable model systems for the ...

Address correspondence to Shoichiro Tsukita, M.D., Ph.D., Department of Cell Biology, Faculty of Medicine, Kyoto University, Sakyo-ku, Kyoto 606-8501, Japan. Tel.: 81-75-753-4372. Fax: 81-75-753-4660. E-mail:htsukita @mfour.med.kyoto-u.ac.jp 1 Abbreviations used in this paper: CPE, Clostridium perfringens enterotoxin; TJ, tight junction. In vertebrates, tight junctions (TJs) 1 play a central ro...

channel pores where no very long jumps are possible. For pores with an elevation that varies like a random walk (red) and alternating pores (blue) the scaled mean square displacement /t is asymp-totically constant. 1. Introduction In general, diffusion of gas particles depends on the collisions between the gas molecules as well as on the collisions of the gas with the pore walls. Of pa...

Pardaxins are a class of ichthyotoxic peptides isolated from fish mucous glands. Pardaxins physically interact with cell membranes by forming pores or voltage-gated ion channels that disrupt cellular functions. Here we report the high-resolution structure of synthetic pardaxin Pa4 in sodium dodecylphosphocholine micelles, as determined by (1)H solution NMR spectroscopy. The peptide adopts a ben...

The history of the investigations into interalveolar communications (pores of Kohn) shows that the question whether they exist and, if so, their nature has for approximately a century been contentious. The present electron microscopic study of the lungs of mice demonstrates that alveolar pores are normal structures, with edges composed of intact alveolar wall. A number of planes are demonstrate...