NO is an important regulatory molecule in eukaryotes. Much of its effect is ascribed to the action of NO as a signalling molecule. However, NO can also directly modify proteins thus affecting their activities. Although the signalling functions of NO are relatively well recognized in plants, very little is known about its potential influence on the structural integrity of plant cells. In this st...

To determine whether or-smooth muscle (ar-SM) isoactin is expressed in the maturing kidney as well as the changes associated with maturation, we processed for immunocytochemistry kidney sections from Wistar-Kyoto rats at various prenatal (15, 17, 19, and 20 days) and postnatal (2, 5,10,15, and 90 days) ages using a monoclonal anti-or-SM actin antibody. At 15 days of gestation, only a few mesenc...

Hair cells, the inner ear's sensory cells, are characterized by tens to hundreds of actin-rich stereocilia that form the hair bundle apparatus necessary for mechanoelectrical transduction. Both the number and length of actin filaments are precisely regulated in stereocilia. Proper cochlear and vestibular function also depends on actin filaments in nonsensory supporting cells. The formation of a...

By combining transmission electron microscopy (TEM), scanning electron microscopy (SEM) and immunocytochemistry at both light and TEM levels the organization of actin in early chick ectoderm has been demonstrated. Every cell is encircled by a ring of actin filaments which are associated with apically situated intercellular junctions. In this way the actin ring of each individual cell is connect...

Ahnak, a 700 kDa protein, is expressed in a variety of cells and has been implicated in different cell-type-specific functions. In the human heart, we observed an endogenous carboxyl-terminal 72 kDa ahnak fragment that copurified with myofibrillar proteins. Immunocytochemistry combined with confocal microscopy localized this fragment to the intercalated discs and close to the Z-line of cardiomy...

Hirano bodies are eosinophilic, rod-shaped intraneuronal inclusions whose frequency increases with age and with Alzheimer's disease. To investigate their composition and possible relationship to the neuronal cytoskeleton, we employed immunocytochemistry and immunoelectronmicroscopy by using antisera to cytoskeletal proteins. The presence of actin, alpha-actinin, vinculin and tropomyosin was dem...

F-actin has been identified in the preprophase band of Allium cepa. Cells attached to subbed slides were obtained from formaldehyde-fixed root tips digested in EGTA and Cellulysin. The air-dried cells were extracted in Triton X-100, treated with rhodamine-phalloidin, rinsed briefly in PBS, and viewed in the fluorescence microscope. Interphase cells contain a network of actin fibers that extends...

Calcium and phospholipid binding proteins have been identified and localized by immunocytochemistry in a wide range of cells and tissues. Two of these proteins (calpactins) also bind F-actin and are substrates for tyrosine kinases. The similar membrane-binding properties of these molecules arise from conserved amino acid sequences and a model is proposed for the tertiary structure of a common c...

A prominent feature of neurodegenerative diseases is a loss of specific neuronal populations. The pathophysiological mechanisms responsible are, however, poorly understood. Primary cultures of rodent embryonic neurons represent a useful experimental system for investigation of molecular pathways of neurodegeneration and mechanisms of cell death. Here, we report a technique utilizing triple-labe...

The influence of bacteria on the cytoskeleton of animal cells has been studied extensively only in pathogenic associations. We characterized changes in host cytoskeletal actin induced by the bacterial partner during the onset of a cooperative animal-bacteria association using the squid-vibrio model. Two-dimensional sodium dodecyl sulfate-polyacrylamide gel electrophoresis and Western blot analy...