Deficiency of the RIIâ subunit of PKA affects locomotor activity and energy homeostasis in distinct neuronal populations

Ruimao Zheng, Linghai Yang, Maria A. Sikorski, Linda C. Enns, Traci A. Czyzyk, Warren C. Ladiges, G. Stanley McKnight

Research output: Contribution to journalArticlepeer-review

20 Scopus citations

Abstract

Targeted disruption of RIIβ-protein kinase A (PKA) in mice leads to a lean phenotype, increased nocturnal locomotor activity, and activation of brown adipose tissue. Because RIIβ is abundantly expressed in both white and brown adipose tissue as well as the brain, the contribution of neuronal vs. peripheral PKA to these phe-notypes was investigated. We used a Cre-Lox strategy to reexpress RIIβ in a tissue-specific manner in either adipocytes or neurons. Mice with adipocyte-specific RIIβ reexpression remained hyperactive and lean, but pan-neuronal RIIβ reexpression reversed both phenotypes. Selective RIIβ reexpression in all striatal medium spiny neurons with Darpp32-Cre corrected the hyperlocomotor phenotype, but the mice remained lean. Further analysis revealed that RIIβ reexpression in D2 dopamine receptor-expressing medium spiny neurons corrected the hyperlocomotor phenotype, which demonstrated that the lean phe-notype in RIIβ-PKA- deficient mice does not develop because of increased locomotor activity. To identify the neurons responsible for the lean phenotype, we used specific Cre-driver mice to reexpress RIIβ in agouti-related peptide (AgRP)-, proopiomelanocortin (POMC)-, single-minded 1 (Sim1)-, or steroidogenic factor 1 (SF1)-expressing neurons in the hypothalamus, but observed no rescue of the lean phenotype. However, when RIIβ was reexpressed in multiple regions of the hypothalamus and striatum driven by Rip2-Cre, or specifically in GABAergic neurons driven by Vgat-ires-Cre, both the hyperactive and lean phenotypes were completely corrected. Bilateral injection of adeno-associated virus1 (AAV1)-Cre directly into the hypothalamus caused reexpression of RIIβ and partially reversed the lean pheno-type. These data demonstrate that RIIβ-PKA deficiency in a subset of hypothalamic GABAergic neurons leads to the lean phenotype.

Original languageEnglish (US)
Pages (from-to)E1631-E1640
JournalProceedings of the National Academy of Sciences of the United States of America
Volume110
Issue number17
DOIs
StatePublished - Apr 23 2013

All Science Journal Classification (ASJC) codes

  • General

Fingerprint Dive into the research topics of 'Deficiency of the RIIâ subunit of PKA affects locomotor activity and energy homeostasis in distinct neuronal populations'. Together they form a unique fingerprint.

Cite this