Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
6
pubmed:dateCreated
2002-3-15
pubmed:abstractText
Endosomes are essential to dendritic and synaptic function in sorting membrane proteins for degradation or recycling, yet little is known about their locations near synapses. Here, serial electron microscopy was used to ascertain the morphology and distribution of all membranous intracellular compartments in distal dendrites of hippocampal CA1 pyramidal neurons in juvenile and adult rats. First, the continuous network of smooth endoplasmic reticulum (SER) was traced throughout dendritic segments and their spines. SER occupied the cortex of the dendritic shaft and extended into 14% of spines. Several types of non-SER compartments were then identified, including clathrin-coated vesicles and pits, large uncoated vesicles, tubular compartments, multivesicular bodies (MVBs), and MVB-tubule complexes. The uptake of extracellular gold particles indicated that these compartments were endosomal in origin. Small, round vesicles and pits that did not contain gold were also identified. The tubular compartments exhibited clathrin-coated tips consistent with the genesis of these small, presumably exosomal vesicles. Approximately 70% of the non-SER compartments were located within or at the base of dendritic spines. Overall, only 29% of dendritic spines had endosomal compartments, whereas 20% contained small vesicles. Small vesicles did not colocalize in spines with endosomes or SER. Three-dimensional reconstructions revealed that up to 20 spines shared a recycling pool of plasmalemmal proteins rather than maintaining independent stores at each spine.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Mar
pubmed:issn
1529-2401
pubmed:author
pubmed:issnType
Electronic
pubmed:day
15
pubmed:volume
22
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
2215-24
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
2002
pubmed:articleTitle
Endosomal compartments serve multiple hippocampal dendritic spines from a widespread rather than a local store of recycling membrane.
pubmed:affiliation
Department of Biology, Boston University, Boston, Massachusetts 02215, USA.
pubmed:publicationType
Journal Article, In Vitro, Research Support, U.S. Gov't, P.H.S.