Linked Life Data

2113575

Source:http://linkedlifedata.com/resource/pubmed/id/2113575

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
3
pubmed:dateCreated
1990-7-27
pubmed:abstractText
The Drosophila mutant, shibirets1 (shits1), is paralyzed at restrictive temperatures (greater than 29 degrees C) by a reversible block in synaptic transmission. Heat pulses deplete synaptic vesicles in nerve terminals and inhibit endocytic internalization of plasma membrane in garland cells and oocytes. In dissociated cultures of larval central nervous system (CNS), a temperature-sensitive defect is also expressed in shits1 neurons: at 30 degrees C, growth cone formation is retarded and neurite outgrowth is arrested. We now report that we have examined constitutive endocytosis in Drosophila CNS culture and have demonstrated directly an endocytic defect in shits1 neurons. At the permissive temperature, 20-22 degrees C, both shits1 and wild-type neurons actively endocytosed fluorescein-labelled dextran (40 KD, 5%) or horseradish peroxidase (HRP, 1%). Within 5 min, HRP was seen in vesicles, cup-shaped bodies, tubules and multivesicular bodies in neurites and cell bodies. In contrast, endocytosis was inhibited in cultures derived from the temperature-sensitive paralytic shits1 by a 15 min heat pulse (30 degrees C). Even after 30 min of HRP exposure at 30 degrees C, HRP-containing membranes were absent from almost all shits1 neurites; a minority of cell bodies had a few HRP-containing vesicles. The temperature-dependent block in endocytosis was readily reversed at 20 degrees C. Interestingly, the block was overcome by high concentration of external cations: shits1 neurons in culture actively took up HRP in numerous vesicles at 30 degrees C if 18 mM Ca2+ or Mg2+ was added to the medium. Our results support the notion that membrane recycling plays a critical role in regulating neurite outgrowth. This study also provides baseline information for further mutational analysis of the mechanism underlying the membrane cycling process in cultured neurons.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Apr
pubmed:issn
0167-7063
pubmed:author
pubmed:issnType
Print
pubmed:volume
6
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
191-206
pubmed:dateRevised
2008-11-21
pubmed:meshHeading
pubmed:year
1990
pubmed:articleTitle
Reversible inhibition of endocytosis in cultured neurons from the Drosophila temperature-sensitive mutant shibirets1.
pubmed:affiliation
Department of Biology, University of Iowa, Iowa City 52242.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't