The identification of synaptic bulbs at the electron accompanied by attempts to study their fate after microscope level and the description of their major the interruption of parent fibers (1) . The degeneracytological characteristics (mitochondria, synaptive changes in organelles of synaptic bulbs were tic vesicles, and junctional densities) were soon well described by De Robertis, but several...

Living organisms compartmentalize their catalytic reactions in membranes for increased efficiency and selectivity. To mimic the organelles of eukaryotic cells, we develop a mild approach situ encapsulating enzymes aqueous-core silica nanocapsules. In order to confine sol-gel reaction at water/oil interface miniemulsion, introduce an aminosilane precursors, which serves as both catalyst amphiphi...

An optimal pH is maintained in each secretory and endocytic organelle by the balance between active H(+) pumping and passive H(+) efflux. The progressive acidification of secretory organelles does not reflect an increased proton pumping activity but rather the decreased conduction of a "proton leak" pathway resembling the recently cloned voltage-gated proton channels.

Genes in mitochondria and chloroplasts are co-located with their gene products to permit regulation of trans-membrane electron transport at the energetic boundary of the cell.

Highly purified lysosomes, rough and smooth endoplasmic reticulum, and Golgi apparatus, as well as microvillus plasma membranes, bound 125I-labelled epidermal growth factor ([125I]EGF) with similar affinity. Scatchard plots for all the organelles were curvilinear. The apparent number of available binding sites per mg protein of intracellular organelles was 27-71% of that found in microvillus pl...

Liberated by enzymatic lysis of the cells, the flagella of Rhodospirillum rubrum, R. molischianum, and R. fulvum all have a similar structure. The hook at the base of the flagellum is connected by a short, narrow collar to a paired disc in the basal organelle. This paired disc is in turn connected to a second paired disc. The disposition of flagella to which fragments of the cell membrane still...

Cilia and flagella are characteristic cellular appendages widely present in diverse animal phyla, as well as in some algae; motility of these organelles results from interactions within a rather organized array of axial microtubules, well known as the “9+2 complex”. High resolution transmission electron microscopy studies of different cilia, along with data of physical parameters, biochemistry,...

Secretory processes play an important role on the biology and life cycles of parasitic protozoa. This review focus on basic aspects, from a cell biology perspective, of the secretion of (a) micronemes, rhoptries and dense granules in members of the Apicomplexa group, where these organelles are involved in the process of protozoan penetration into the host cell, survival within the parasitophoro...