Adenosine receptors: expression, function and regulation.
Adenosine receptors (ARs) comprise a group of G protein-coupled receptors (GPCR) which mediate the physiological actions of adenosine. To date, four AR subtypes have been cloned and identified in different tissues. These receptors have distinct localization, signal transduction pathways and different means of regulation upon exposure to agonists. This review will describe the biochemical characteristics and signaling cascade associated with each receptor and provide insight into how these receptors are regulated in response to agonists. A key property of some of these receptors is their ability to serve as sensors of cellular oxidative stress, which is transmitted by transcription factors, such as nuclear factor (NF)-κB, to regulate the expression of ARs. Recent observations of oligomerization of these receptors into homo- and heterodimers will be discussed. In addition, the importance of these receptors in the regulation of normal and pathological processes such as sleep, the development of cancers and in protection against hearing loss will be examined.
Department of Pharmacology and Neuroscience, Southern Illinois University School of Medicine, Springfield, IL 62702, USA. ssheth@siumed.edu.
Sandeep
S
Sheth
Department of Pharmacology and Neuroscience, Southern Illinois University School of Medicine, Springfield, IL 62702, USA. rafaelbs2002@yahoo.com.br.
Rafael
R
Brito
Department of Surgery (Otolaryngology), Southern Illinois University School of Medicine, Springfield, IL 62702, USA. dmukherjea@siumed.edu.
Debashree
D
Mukherjea
Department of Pharmacology and Neuroscience, Southern Illinois University School of Medicine, Springfield, IL 62702, USA. lrybak@siumed.edu.
Leonard P
LP
Rybak
Department of Pharmacology and Neuroscience, Southern Illinois University School of Medicine, Springfield, IL 62702, USA. vramkumar@siumed.edu.
Vickram
V
Ramkumar
D000818:Animals; D005786:Gene Expression Regulation; D034381:Hearing Loss / Q000235:genetics / Q000378:metabolism / Q000517:prevention & control; D006801:Humans; D016328:NF-kappa B / Q000235:genetics; D009369:Neoplasms / Q000235:genetics / Q000378:metabolism; D010766:Phosphorylation; D055503:Protein Multimerization; D058906:Purinergic P1 Receptor Agonists / Q000494:pharmacology; D018047:Receptors, Purinergic P1 / Q000502:physiology*; D015398:Signal Transduction; D012890:Sleep / Q000502:physiology
D016328:NF-kappa B; D058906:Purinergic P1 Receptor Agonists; D018047:Receptors, Purinergic P1