Fragile X related protein 1 clusters with ribosomes and messenger RNAs at a subset of dendritic spines in the mouse hippocampus.
The formation and storage of memories in neuronal networks relies on new protein synthesis, which can occur locally at synapses using translational machinery present in dendrites and at spines. These new proteins support long-lasting changes in synapse strength and size in response to high levels of synaptic activity. To ensure that proteins are made at the appropriate time and location to enable these synaptic changes, messenger RNA (mRNA) translation is tightly controlled by dendritic RNA-binding proteins. Fragile X Related Protein 1 (FXR1P) is an RNA-binding protein with high homology to Fragile X Mental Retardation Protein (FMRP) and is known to repress and activate mRNA translation in non-neuronal cells. However, unlike FMRP, very little is known about the role of FXR1P in the central nervous system. To understand if FXR1P is positioned to regulate local mRNA translation in dendrites and at synapses, we investigated the expression and targeting of FXR1P in developing hippocampal neurons in vivo and in vitro. We found that FXR1P was highly expressed during hippocampal development and co-localized with ribosomes and mRNAs in the dendrite and at a subset of spines in mouse hippocampal neurons. Our data indicate that FXR1P is properly positioned to control local protein synthesis in the dendrite and at synapses in the central nervous system.
Department of Neurology and Neurosurgery, The Research Institute of the McGill University Health Centre, Montreal General Hospital, Montreal, Quebec, Canada.
Denise
D
Cook
Maria del Rayo
Mdel R
Sanchez-Carbente
Claude
C
Lachance
Danuta
D
Radzioch
Sandra
S
Tremblay
Edouard W
EW
Khandjian
Luc
L
DesGroseillers
Keith K
KK
Murai
D000818:Animals; D016000:Cluster Analysis; D049229:Dendritic Spines / Q000378:metabolism*; D000076122:Disks Large Homolog 4 Protein; D005260:Female; D051860:Fragile X Messenger Ribonucleoprotein 1 / Q000378:metabolism*; D049452:Green Fluorescent Proteins / Q000378:metabolism; D051528:Guanylate Kinases / Q000378:metabolism; D057809:HEK293 Cells; D006624:Hippocampus / Q000166:cytology / Q000254:growth & development / Q000378:metabolism*; D006801:Humans; D008297:Male; D008565:Membrane Proteins / Q000378:metabolism; D051379:Mice; D008810:Mice, Inbred C57BL; D009474:Neurons / Q000166:cytology / Q000378:metabolism; D011132:Polyribosomes / Q000378:metabolism; D021381:Protein Transport; D034443:RNA Transport; D012333:RNA, Messenger / Q000378:metabolism; D011993:Recombinant Fusion Proteins / Q000378:metabolism; D054657:Ribosome Subunits / Q000378:metabolism; D012270:Ribosomes / Q000378:metabolism*; D014020:Tissue Extracts
D000076122:Disks Large Homolog 4 Protein; D051860:Fragile X Messenger Ribonucleoprotein 1; D049452:Green Fluorescent Proteins; D051528:Guanylate Kinases; D008565:Membrane Proteins; D012333:RNA, Messenger; D011993:Recombinant Fusion Proteins; D014020:Tissue Extracts; C501447:Dlg4 protein, mouse; C485184:enhanced green fluorescent protein