Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0153640 (Cerebellum)
 1,777 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The developmental patterns of calmodulin-binding proteins (CaM-BPS) in rat brain were examined using biotinylated calmodulin overlays of one- and two-dimensional gels. Hippocampus showed the earliest onset of CaM-BP expression (postnatal day 5; PND5), followed by cerebral cortex and striatum, both of which had detectable levels of CaM-BPs by PND7. Cerebellum had the latest onset of CaM-BP expression; CaM-BPs were not detectable until PND9. Very few CaM-BPs were present in brain before PND5 and all regions reached near adult levels by PND20. However, several unique CaM-BPs were seen in embryonic brain and these proteins may have an important role in developing neurons. These data suggest an orderly, complex expression of CaM-BPs which increases during times of synaptogenesis and synaptic maturation.
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PMID:Developmental expression of neuronal calmodulin-binding proteins in rat brain. 235 Aug 82

Postsynaptic densities (PSDs) have been isolated from cerebral cortex, midbrain, cerebellum, and brain stem by the Triton X-100 method previously used in the isolation of cerebral PSDs (Cohen et al., 1977, J. Cell Biol. 74:181). These PSDs have been compared in protein composition, protein phosphorylation, and morphology. Thin-section electron microscopy revealed that cerebral cortex and midbrain PSDs were identical, being approximately 57 nm thick and composed of apparent aggregates 20-30 nm in diameter. Isolated cerebellar PSDs appeared thinner (33 nm) than cerebral cortex PSDs and lacked the apparent 20- to 30-nm aggregates, but had a latticelike structure. In unidirectional and rotary-shadowed replicas, the cerebrum and midbrain PSDs were circular in shape with a large central perforation or hole in the center of them. Cerebellum PSDs did not have a large perforation, but did have numerous smaller perforations in a lattice like structure. Filaments (6-9 nm) were observed connecting possible 20- to 30-nm aggregates in cerebrum PSDs and were also observed radiating from one side of the PSD. Both cerebral cortex and midbrain PSDs exhibited identical protein patterns on SDS gel electrophoresis. In comparison, cerebellar PSDs (a) lacked the major 51,000 Mr protein, (b) contained two times less calmodulin, and (c) contained a unique protein at 73,000 Mr. Calcium plus calmodulin stimulated the phosphorylation of the 51,000 and 62,000 Mr bands in both cerebral cortex and midbrain PSDs. In cerebellar PSDs, only the 58,000 and 62,000 Mr bands were phosphorylated. In the PSDs from all brain regions, cAMP stimulated the phosphorylation of Protein Ia (73,000 Mr), Protein Ib (68.000 Mr), and a 60,000 Mr protein, although cerebrum and midbrain PSDs contained very much higher levels of phosphorylated protein than did the cerebellum. On the basis of the morphological criteria, it is possible that PSDs isolated from cerebrum and midbrain were derived from the Gray type I, or asymmetric, synapses, whereas cerebellum PSDs were derived from the Gray type II, or symmetric, synapses. Since there is some evidence that the type I synapses are involved in excitatory mechanisms while the type II are involved in inhibitory mechanisms, the role of the PSD and of some of its proteins in these synaptic responses is discussed.
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PMID:Isolation and characterization of postsynaptic densities from various brain regions: enrichment of different types of postsynaptic densities. 741 Apr 81

Several studies point to the importance of peptides and proteolysis in Alzheimer's disease (AD). Because of its ability to study small proteins and peptides, reverse-phase HPLC was employed to study these species in AD. Cerebellum was chosen for these initial studies because it does not show significant neuronal loss but does show some pathology in AD. Examination of over 600 peptide peaks per case revealed 15 that were elevated in AD. Nine were fragments of hemoglobin, and the remainder included two species of calmodulin, two of myelin basic protein, and one each of 67 kDa neurofilament protein and PEP-19. The cleavage sites on hemoglobin were after hydrophobic residues and immunolocalization was seen preferentially around blood vessel walls and granule cells. The elevation of the non-serum-derived peptides was characteristic of general metabolic changes that occurred in AD cerebellum, and the presence of elevated hemoglobin polypeptides indicated either possible disruption of the blood-brain barrier or selective evasion of it by peptidaceous products. Further studies are required to establish whether hemoglobin fragments have a role in neurodegenerative processes such as AD.
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PMID:Increased levels of hemoglobin-derived and other peptides in Alzheimer's disease cerebellum. 751 35

Store-operated Ca(2+) entry (SOCE) has been extensively studied in non-neuronal cells, such as glial cells and smooth muscle cells, in which Ca(2+)-independent phospholipase A(2) (iPLA(2)) has been shown to play a key role in the regulation of SOCE channels. In the present study, we have investigated the role of iPLA(2) for store-operated Ca(2+) entry in rat cerebellar granule neurons in acute brain slices using confocal Ca(2+) imaging. Depletion of Ca(2+) stores by cyclopiazonic acid (CPA) induced a Ca(2+) influx, which could be inhibited by SOCE channel blockers 2-aminoethoxy-diphenylborate (2-APB) and 3,5-bistrifluoromethyl pyrazole derivative (BTP2), but not by the voltage-operated Ca(2+) channel blocker diltiazem and by the Na+ channel blocker tetrodotoxin. The inhibitors of iPLA(2), bromoenol lactone (BEL) and 1,1,1-trifluoro-2-heptadecanone, and the selective suppression of iPLA(2) expression by antisense oligodeoxynucleotides, inhibited CPA-induced Ca(2+) influx. Calmidazolium, which relieves the block of inhibitory calmodulin from iPLA(2), elicited a Ca(2+) influx similar to CPA-induced Ca(2+) entry. The product of iPLA(2), lysophosphatidylinositol, elicited a 2-APB- and BTP2-sensitive, but BEL-insensitive, Ca(2+) influx. Spontaneous Ca(2+) oscillations in granule cells in acute brain slices were reduced after inhibiting iPLA(2) activity or by blocking SOCE channels. The results suggest that depletion of Ca(2+) stores activates iPLA(2) to trigger Ca(2+) influx by the formation of lysophospholipids in these neurons.
Cerebellum 2008
PMID:Calcium-independent phospholipase A2 mediates store-operated calcium entry in rat cerebellar granule cells. 1878 73