Actin-binding proteins in a postsynaptic preparation: Lasp-1 is a component of central nervous system synapses and dendritic spines.
CNS synapses are complex sites of cell-cell communication. Identification and characterization of the protein components of synapses will lead to a better understanding of the mechanisms of neurotransmission and plasticity. We applied multidimensional protein identification technology (MudPIT) to purified, guanidine-solubilized postsynaptic fractions to identify novel synaptically localized molecules. We identified several actin-associated proteins known to regulate actin polymerization and control cell motility in nonneural cells that have not previously been associated with CNS synaptic function. One of these is lasp-1, an actin-associated LIM and SH3 domain-containing protein. We show that lasp-1 is strongly expressed by CNS neurons and is concentrated at synaptic sites. Overall, the preponderance of actin-associated proteins in postsynaptic density fractions, and specifically those involved in actin reorganization, suggests that there are many modes by which the state of synaptic F-actin polymerization and, hence, synaptic physiology are affected.
Phillips
Greg R
GR
Fishberg Department of Neuroscience, Mount Sinai School of Medicine, New York, New York 10029, USA. greg.phillips@mssm.edu
Anderson
Tonya R
TR
Florens
Laurence
L
Gudas
Christopher
C
Magda
Gabriela
G
Yates
John R
JR
Colman
David R
DR
D000199:Actins / Q000378:metabolism*; D048868:Adaptor Proteins, Signal Transducing; D000818:Animals; D001921:Brain / Q000378:metabolism* / Q000648:ultrastructure; D002478:Cells, Cultured; D003598:Cytoskeletal Proteins; D016054:DNA, Protozoan; D003712:Dendrites / Q000737:chemistry / Q000378:metabolism* / Q000648:ultrastructure; D018398:Homeodomain Proteins / Q000096:biosynthesis / Q000378:metabolism / Q000648:ultrastructure; D060588:LIM Domain Proteins; D008297:Male; D008840:Microfilament Proteins / Q000096:biosynthesis / Q000378:metabolism* / Q000648:ultrastructure; D009363:Neoplasm Proteins / Q000096:biosynthesis / Q000378:metabolism / Q000648:ultrastructure; D009419:Nerve Tissue Proteins / Q000096:biosynthesis / Q000378:metabolism* / Q000648:ultrastructure; D051381:Rats; D017207:Rats, Sprague-Dawley; D013570:Synaptic Membranes / Q000737:chemistry / Q000378:metabolism* / Q000648:ultrastructure
D000199:Actins; D048868:Adaptor Proteins, Signal Transducing; D003598:Cytoskeletal Proteins; D016054:DNA, Protozoan; D018398:Homeodomain Proteins; C096353:LASP1 protein, human; D060588:LIM Domain Proteins; C495806:Lasp1 protein, rat; D008840:Microfilament Proteins; D009363:Neoplasm Proteins; D009419:Nerve Tissue Proteins