A chromodomain-containing nuclear protein, MRG15 is expressed as a novel type of dendritic mRNA in neurons.
On the basis of a hypothesis that proteins encoded by the mRNAs that are transported to and translated at the dendrites/synapses may play key roles in synaptic plasticity, this study reports on attempts to isolate mRNAs which are localizing at the dendrites/synapses from mouse cerebellar synaptosomal fractions. Among 100 pieces of dendritic mRNA candidates, 10 pieces of mRNAs were found to contain the cytoplasmic polyadenylation element (CPE)-like sequences which were contained in certain mRNAs translated in dendrites. We next examined the issue of whether the CPE-like sequence-containing mRNAs (CPERs) were localized in the synapses/dendrites by means of in situ hybridization. The findings indicate that CPER9 was actually localized at the apical dendrites of a portion of cerebral cortex layer V pyramidal cells, as well as at the proximal dendrites of some of the cerebellar Purkinje cells. CPER9 was found to encode a mouse homolog of MRG15, a nuclear protein which contains a chromodomain identified in several proteins that act as regulators of transcription. Immunohistochemistry with anti-MRG15 antibodies revealed that MRG15 was localized in dendrites as well as in the nuclei of Purkinje cells. These results suggest that MRG15 may serve as a link between synaptic activity and gene expression.
Matsuoka
Yuriko
Y
Department of Cell Biology and Neuroscience, Graduate School of Medicine, Osaka University, 2-2 Yamada-oka, Suita, 565-0871, Osaka, Japan.
Matsuoka
Yosuke
Y
Shibata
Satoshi
S
Ban
Tadanobu
T
Toratani
Naomi
N
Shigekawa
Minoru
M
Ishida
Hidekazu
H
Yoneda
Yoshihiro
Y
D000818:Animals; D000918:Antibody Specificity / Q000276:immunology; D001483:Base Sequence / Q000235:genetics; D001921:Brain / Q000166:cytology / Q000254:growth & development* / Q000378:metabolism; D002451:Cell Compartmentation / Q000502:physiology; D002525:Cerebellar Cortex / Q000166:cytology / Q000378:metabolism; D002540:Cerebral Cortex / Q000166:cytology / Q000378:metabolism; D003712:Dendrites / Q000378:metabolism* / Q000648:ultrastructure; D015870:Gene Expression / Q000502:physiology; D007150:Immunohistochemistry; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D009687:Nuclear Proteins / Q000235:genetics* / Q000378:metabolism*; D017729:Presynaptic Terminals / Q000378:metabolism* / Q000648:ultrastructure; D017434:Protein Structure, Tertiary / Q000235:genetics; D011689:Purkinje Cells / Q000166:cytology / Q000378:metabolism; D017966:Pyramidal Cells / Q000166:cytology / Q000378:metabolism; D012333:RNA, Messenger / Q000235:genetics / Q000302:isolation & purification*; D016601:RNA-Binding Proteins / Q000235:genetics / Q000378:metabolism; D017386:Sequence Homology, Amino Acid; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism; D039221:mRNA Cleavage and Polyadenylation Factors
C490387:Cpeb1 protein, mouse; C109882:MORF4 protein, human; D009687:Nuclear Proteins; D012333:RNA, Messenger; D016601:RNA-Binding Proteins; D014157:Transcription Factors; D039221:mRNA Cleavage and Polyadenylation Factors