The intercellular junctions in the anterior myoepithelium and posterior pigmented epithelium of the rhesus monkey iris were examined using an ultrastructural tracer, conventional electron microscopy, and the freeze-fracture technique. Within the anterior myoepithelium the lateral cell margins were joined by puncta adhaerentia, desmosomes, and gap junctions. The distribution of the puncta adhaer...

PLEKHA7 is a recently identified protein of the epithelial zonula adhaerens (ZA), and is part of a protein complex that stabilizes the ZA, by linking it to microtubules. Since the ZA is important in the assembly and disassembly of tight junctions (TJ), we asked whether PLEKHA7 is involved in modulating epithelial TJ barrier function. We generated clonal MDCK cell lines in which one of four diff...

Further detailed observation has been made on the ultrastructure of the six strains of Yoshida ascites hepatoma representing various growth rates and pathological characteristics. Common to all the ascites hepatoma were the large, irregular nuclei with hypertrophied nucleoli, increased free ribosomes, and no microbodies. The present investigation throughout many transplant generations has revea...

Retinoids are vital for normal embryonic development and are necessary during postnatal development and adulthood for the maintenance of the reproductive and nervous system and for visual pigment synthesis. STRA6 (Stimulated by retinoic acid 6) is the cell surface receptor for retinol binding protein (RBP4), which facilitates the cellular uptake of retinol. Mutations in Stra6 are responsible fo...

The Muscleblind (MBL) protein family is a deeply conserved family of RNA binding proteins that regulate alternative splicing, alternative polyadenylation, RNA stability and RNA localization. Their inactivation due to sequestration by expanded CUG repeats causes symptoms in the neuromuscular disease myotonic dystrophy. MBL zinc fingers are the most highly conserved portion of these proteins, and...

Trichoplax adhaerens has only six cell types. The function as well as the structure of crystal cells, the least numerous cell type, presented an enigma. Crystal cells are arrayed around the perimeter of the animal and each contains a birefringent crystal. Crystal cells resemble lithocytes in other animals so we looked for evidence they are gravity sensors. Confocal microscopy showed that their ...

Aggregation of adult rat hepatocytes, isolated by the collagenase perfusion technique, was studied by ultrastructural methods and the indirect immunofluorescence technique using anti-actin antibodies. In a primary culture the cells rapidly made contact with each other by filopodia-like structures, as seen by scanning electron microscopy. In a few hours this led to stable adhesion of the cells. ...

Dicer proteins are highly conserved, are present in organisms ranging from plants to metazoans, and are essential components of the RNA interference pathway. Although the complement of Dicer proteins has been investigated in many "higher" metazoans, there has been no corresponding characterization of Dicer proteins in any early-branching metazoan. We cloned partial cDNAs of genes belonging to t...

The insect chemoreceptor superfamily consists of 2 gene families, the highly diverse gustatory receptors (GRs) found in all arthropods with sequenced genomes and the odorant receptors that evolved from a GR lineage and have been found only in insects to date. Here, I describe relatives of the insect chemoreceptor superfamily, specifically the basal GR family, in diverse other animals, showing t...