Loss of the serum response factor in the dopamine system leads to hyperactivity.
The serum response factor (SRF) is a key regulator of neural development and cellular plasticity, which enables it to act as a regulator of long-term adaptations in neurons. Here we performed a comprehensive analysis of SRF function in the murine dopamine system. We found that loss of SRF in dopaminoceptive, but not dopaminergic, neurons is responsible for the development of a hyperactivity syndrome, characterized by reduced body weight into adulthood, enhanced motor activity, and deficits in habituation processes. Most important, the hyperactivity also develops when the ablation of SRF is induced in adult animals. On the molecular level, the loss of SRF in dopaminoceptive cells is associated with altered expression of neuronal plasticity-related genes, in particular transcripts involved in calcium ion binding, formation of the cytoskeleton, and transcripts encoding neuropeptide precursors. Furthermore, abrogation of SRF causes specific deficits in activity-dependent transcription, especially a complete lack of psychostimulant-induced expression of the Egr genes. We inferred that alterations in SRF-dependent gene expression underlie the observed hyperactive behavior. Thus, SRF depletion in dopaminoceptive neurons might trigger molecular mechanisms responsible for development of psychopathological conditions involving hyperactivity.
Parkitna
Jan Rodriguez
JR
Molecular Biology of the Cell I, German Cancer Research Center, Im Neuenheimer Feld 280, D-69120 Heidelberg, Germany.
Bilbao
Ainhoa
A
Rieker
Claus
C
Engblom
David
D
Piechota
Marcin
M
Nordheim
Alfred
A
Spanagel
Rainer
R
Schütz
Günther
G
D000818:Animals; D004298:Dopamine / Q000502:physiology*; D005786:Gene Expression Regulation; D006948:Hyperkinesis / Q000209:etiology; D051379:Mice; D009473:Neuronal Plasticity / Q000235:genetics; D009474:Neurons / Q000378:metabolism*; D011595:Psychomotor Agitation / Q000209:etiology*; D011596:Psychomotor Disorders / Q000209:etiology; D026362:Serum Response Factor / Q000032:analysis / Q000172:deficiency*; D013851:Thinness; D014158:Transcription, Genetic
D026362:Serum Response Factor; D004298:Dopamine