Recently, the gene encoding clathrin assembly protein of lymphoid myeloid leukemia (CALM), which is homologous to the AP180, was cloned from rat brain, and its expression differential to AP180 was reported (Kim and Lee, 1999). This gene product promotes the polymerization of clathrin into clathrin cage and found to be a regulator in membrane trafficking between intracellular compartments in eukaryotic cells (Kim et al., 2000). In this study, we have purified the CALM protein from clathrin-coated vesicles of rat liver using the monoclonal antibody against the recombinant N-terminal region of the CALM. The coated proteins extracted from the coated vesicle fraction was further purified by multi-step procedures involving gel-filtration and ion-exchange chromatography and SDS-PAGE. The purified protein with an apparent molecular weight of 100 kD promoted the assembly of clathrin triskelia into clathrin cage. In this respect the CALM protein bears a functional resemblance to the AP180 that has been previously described.
Animal ; Clathrin/*metabolism ; Clathrin-Coated Vesicles/*chemistry ; Liver/*chemistry ; Nerve Tissue Proteins/*isolation & purification ; Phosphoproteins/*isolation & purification ; Rats

As the basic physiological function of synapses, vesicle cycling involves in many aspects of process. Among them, vesicle recycling is the basis of synaptic vesicle cycling. Studies show that clathrin mediated endocytosis is a major pathway of vesicle recycling, in which Dynamin plays an important role. Dynamin is a GTPases with molecular weight of 100 kD, which acts as "scissors" in the endocytosis, separating the clathrin coated pits from membrane. It has been found that Dynamin is associated with epilepsy, Alzheimer's disease, centronuclear myopathy, and several other neurological diseases. In this paper, we discussed the structure, function and regulation of Dynamin, and reviewed recent advance in the studies on Dynamin related diseases.
Clathrin ; physiology ; Coated Pits, Cell-Membrane ; physiology ; Dynamins ; physiology ; Endocytosis ; Humans ; Synapses ; physiology ; Synaptic Transmission ; Synaptic Vesicles ; physiology

Histiocytic skin disorders are usually classified as either Langerhans' cell histiocytosis (LCH) or non LCH, based on the pathology. Benign cephalic histiocytosis (BCH) is a rare type of non-Langerhans histiocytitic disorder and is characterized by self-healing multiple small eruptions of yellow to red-brown papules on the face and upper trunk. Histologic features of this disorder show dermal proliferation of histiocytes that have intracytoplasmic comma-shaped bodies, coated vesicles and desmosome-like structures. In this study, we report on a 7-month-old boy who contained small yellow-red papules on his face that spread to his upper trunk. The clinical and histologic features in this patient were consistent with BCH.
Coated Vesicles ; Histiocytes ; Histiocytosis ; Humans ; Infant ; Skin ; Xanthogranuloma, Juvenile

A 18-month-old girl was seen because of an yellowish brown papular eruptions on the face, earlobes and neck of one year duration. A skin biopsy specimen revealed circumscribed cellular infiltrates composed of predorninantly pleornorphic histiocytes. Electron microscopy of biopsy material disclosed numerous worm like particles and coated vescles in limited area of the cell cytoplasm, consistent with the findinga described in benign cephalic histiocytosis. After six months of her first visit, the individual papules became flattened.
Biopsy ; Coated Vesicles ; Cytoplasm ; Female ; Histiocytes ; Histiocytosis* ; Humans ; Infant ; Microscopy, Electron ; Neck ; Skin

Clathrin-coated vesicles (CCVs) are involved in protein and lipid trafficking between intracellular compartments in eukaryotic cells. CCVs are composed of clathrin and assembly proteins. The clathrin assembly protein lymphoid myeloid leukemia (CALM) gene, encodes a homologoue of the neuronal clathrin assembly protein AP180. In this study, we characterized the properties of the CALM expressed in E. coli. The molecular weight of bacterially expressed GST-CALM fusion protein was approximately 105 kD on SDS-PAGE. The CALM protein could promote clathrin triskelia into clathrin cages and could bind the preformed clathrin cage. However, 33 kD N-terminal domain of CALM could not bind pre-assembled clathrin cages, but assemble clathrin triskelia into clathrin cages. The CALM protein was bound to SH3 domain through N-terminal domain1, in vitro. The CALM protein is proteolyzed by caspase 3, caspase 8 and calpain through C-terminal domain.
Animal ; Antibodies, Monoclonal ; Calpain/chemistry ; Caspases/chemistry ; Clathrin-Coated Vesicles/metabolism* ; Electrophoresis, Polyacrylamide Gel ; Escherichia coli/metabolism ; Escherichia coli/genetics ; Female ; Glutathione Transferase/genetics* ; Mice ; Mice, Inbred BALB C ; Nerve Tissue Proteins/metabolism ; Nerve Tissue Proteins/metabolism ; Nerve Tissue Proteins/chemistry* ; Phosphoproteins/metabolism ; Phosphoproteins/genetics ; Phosphoproteins/chemistry* ; Protein Binding ; Rabbits ; Recombinant Fusion Proteins/metabolism ; Recombinant Fusion Proteins/genetics ; Recombinant Fusion Proteins/chemistry* ; src Homology Domains

Potassium (K+) balance is achieved by the control of urinary K+ excretion and by the control of K+ absorption from the digestive tract. It has been established that chronic potassium depletion is associated with a remarkable hypertrophy of the collecting duct of the kidney. But, there is no morphological studies regarding the stomach and distal colon during the chronic changes of potassium diet. Electron microscopy was performed to observe the morphological alterations of the stomach and distal colon in response to chronic changes of potassium diet in rat. Electron microscopy of normal parietal cells revealed the presences of many mitochondia, tubulovesicles, and short basal cytoplasmic processes and microvilli in the intracellular canaliculi. In potasium-depleted parietal cells, mito-chondria were increased in size and number, and tubulovesicles almost disappeared, and microvilli in the intracellular canaliculi were increased in number and length, and short basal cytoplasmic processes were also increased in size and number. Parietal cells of potassium-loading after restriction were found to be almost normal. Two types of surface columnar epithelial cells were present in normal distal colon. Type I cells had many mitochondria and abundant coated vesicles in the supranuclear region. Type II cells had moderate amount of mitochondria and relatively fewer coated vesicles. In comparison with normal, potasium-depleted surface columnar epithelial cells had more abundant and larger mitochondria and more numerous and longer (1.4~1.6 times than normal) microvilli. Surface columnar epithelial cells of potassium-loading after restriction were recovered almost to normal. These results suggest that gastric parietal cells and surface columnar epithelial cells of distal colon adapt through morphological changes to preserve potassium balance during chronic changes of potassium diet.
Absorption ; Animals ; Coated Vesicles ; Colon* ; Cytoplasm ; Diet ; Epithelial Cells* ; Gastrointestinal Tract ; Hypertrophy ; Kidney ; Microscopy, Electron ; Microvilli ; Mitochondria ; Parietal Cells, Gastric ; Potassium ; Potassium, Dietary* ; Rabeprazole* ; Rats ; Stomach

The development of the cardiac ganglion was studied by electron microscopy in human fetuses ranging from 30mm to 270mm crown rump length. At 40mm fetus, the cardiac ganglia were observed in the adventitia of both the aorta and pulmonary artery, superior aspect of the left and right atrium, and interatrial septum. The cardiac ganglia were comprised of clusters of undifferentiated cells, neuroblasts, and unmyelinated nerve fibers. The ganglia were small and uncapsulated until 70mm fetus. At 70mm fetus, the cardic ganglia consisted of neuroblasts, satellite cells, and unmyelinated nerve fibers. Each ganglion was ensheathed in a connective tissue capsule. The cytoplasm of neuroblast contained Nissl bodies, mitochondria, coated vesicles, extensive Golgicomplex, and rough endoplasmic reticulum. Synaptic contacts between the cholinergic preganglionic axon and dendrites of postganglionic neuron were first observed. At 100mm fetus, the cardiac ganglia consisted of small clusters of ganglion cells and dendrites, together with supporting elements and blood vessels. During next prenatal stage from 170mm fetus, the ganglion cells were large and each contained a large nucleus with one or more nucleoli. The cytoplasm of ganglion cells contained much rough endoplasmic reticulum and extensive Golgi complex. Cholinergic preganglionic axons were numerous and interposed between the satellite cells. Adrenergic axons were rarely observed. A great number of synaptic junctions between the cholinergic preganglionic axon terminals and the dendrites of postganglinic neuron were found, and a few axosomatic synapses were also observed. Adrenergic nerve terminals did not seem to be involved in the synaptic transmission. The cardiac ganglion cells of the human fetal heart were innervated only by cholinergic nerve.
Adventitia ; Aorta ; Axons ; Blood Vessels ; Coated Vesicles ; Connective Tissue ; Crown-Rump Length ; Cytoplasm ; Dendrites ; Endoplasmic Reticulum, Rough ; Fetal Heart ; Fetus* ; Ganglia ; Ganglion Cysts* ; Golgi Apparatus ; Heart Atria ; Humans* ; Microscopy, Electron ; Mitochondria ; Nerve Fibers, Unmyelinated ; Neurons ; Nissl Bodies ; Presynaptic Terminals ; Pulmonary Artery ; Synapses ; Synaptic Transmission

Caveolin-1 (Cav-1) is a trans-membrane protein that is a major component of the caveolae structure on the plasma membrane. Cav-1 is involved in the regulation of various cellular processes, including cell growth, differentiation, endocytosis, and in particular it has been implied in cellular senescence. Here we review current knowledge about Cav-1 in cellular signaling and discuss the role of Cav-1 in aging-related diseases.
Caveolae ; Caveolin 1 ; Cell Aging ; Cell Membrane ; Endocytosis

Caveolin-2, a protein about 20 kD, is a major component of the inner surface of caveolae, small invaginations of the plasma membrane. Similar with caveolin-1 and caveolin-3, it serves as a protein marker of caveolae. Caveolin-1 and -2 are located next to each other at 7q31.1 on human chromosome, the proteins encoded are co-localized and form a stable hetero-oligomeric complex, distributing similarly in tissue and cultured cells. Caveolin-3 is located on different chromosomes but confirmed to interact with caveolin-2. Caveolin-2 is similar to caveolin-1 in many respects but differs from the latter in functional domains, especially in G-protein binding domain and caveolin scaffolding domain. The mRNAs of both caveolin-1 and caveolin-2 are most abundantly expressed in white adipose tissue and are induced during differentiation of 3T3-L1 cells to adipocytes. Caveolin-2-deficient mice demonstrate clear pulmonary defects, with little or no change in caveolin-1 expression and caveolae formation, suggesting that caveolin-2 plays a selective role in lung functions. Caveolin-2 is also involved in lipid metabolism and human cancers.
Biomarkers ; metabolism ; Caveolae ; metabolism ; Caveolin 2 ; genetics ; metabolism ; Chromosomes, Human, Pair 7 ; Humans

BACKGROUND: Caveolin-1 is a principal component of caveolae membranes in vivo. Although expression of caveolae structure and expression of caveolin family, caveolin-1, -2 and -3, was known in chondrocytes, the functional role of caveolae and caveolins in chondrocytes remains unknown. In this study, we investigated the role of caveolin-1 in articular chondrocytes. METHODS: Rabbit articular chondrocytes were prepared from cartilage slices of 2-week-old New Zealand white rabbits by enzymatic digestion. Caveolin-1 cDNA was transfected to articular chondrocytes using LipofectaminePLUS. The cyclooxygenase-2 (COX-2) expression levels were determined by immunoblot analysis, immunostaining, immunohistochemistry, and prostaglandin E2 (PGE2) assay was used to measure the COX-2 activity. RESULTS: Ectopic expression of caveolin-1 induced COX-2 expression and activity, as indicated by immunoblot analysis and PGE2 assay. And also, overexpression of caveolin-1 stimulated activation of p38 kinase and ERK-1/ -2. Inhibition of p38 kinase and ERK-1/-2 with SB203580 and PD98059, respectively, led to a dose-dependent decrease COX-2 expression and PGE2 production in caveolin-1-transfected cells. CONCLUSION: Taken together, our data suggest that ectopic expression of caveolin-1 contributes to the expression and activity of COX-2 in articular chondrocytes through MAP kinase pathway.
Cartilage ; Caveolae ; Caveolin 1* ; Caveolins ; Chondrocytes* ; Cyclooxygenase 2 ; Digestion ; Dinoprostone ; DNA, Complementary ; Humans ; Immunohistochemistry ; Membranes ; Phosphotransferases* ; Rabbits