Peristalsis is impaired in the small intestine of mice lacking the P2X3 subunit

P2X receptors are ligand-gated ion channels that can bind with the adenosine triphosphate (ATP) and have diverse functional roles in neuropathic pain, inflammation, special sense, and so on. In this study, 180 putative P2X genes, including 176 members in 32 animal species and 4 members in 3 species of lower plants, were identified. These genes were divided into 13 groups, including 7 groups in vertebrates and 6 groups in invertebrates and lower plants, through phylogenetic analysis. Their gene organization and motif composition are conserved in most predicted P2X members, while groupspecific features were also found. Moreover, synteny relationships of the putative P2X genes in vertebrates are conserved while simultaneously experiencing a series of gene insertion, inversion, and transposition. Recombination signals were detected in almost all of the vertebrates and invertebrates, suggesting that intragenic recombination may play a significant role in the evolution of P2X genes. Selection analysis also identified some positively selected sites that acted on the evolution of most of the predicted P2X proteins. The phenomenon of alternative splicing occurred commonly in the putative P2X genes of vertebrates. This article explored in depth the evolutional relationship among different subtypes of P2X genes in animal and plants and might serve as a solid foundation for deciphering their functions in further studies.

Section: Phylogenetic Analysis Of the Putative P2x Genesmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Comparative study of the P2X gene family in animals and plants

Hou

Cao

2016

“…Immunohistochemical studies have localized P2X 2 and P2X 3 subunits to some myenteric neurons in guinea pig [73,75,76]. Recent studies have utilized mice deficient in P2X 2 or P2X 3 receptors to investigate these subtypes in S and AH neurons [78,89]. S neurons in tissues from P2X 2 +/+ mice were depolarized by ATP but not by α,β-mATP.…”

Section: Subtypes Of P2x Receptor One Question Remaining Is Whatmentioning

confidence: 99%

Purinergic receptors and synaptic transmission in enteric neurons

Ren

Bertrand

2007

Purines such as ATP and adenosine participate in synaptic transmission in the enteric nervous system as neurotransmitters or neuromodulators. Purinergic receptors are localized on the cell bodies or nerve terminals of different functional classes of enteric neurons and, with other receptors, form unique receptor complements. Activation of purinergic receptors can regulate neuronal activity by depolarization, by regulating intracellular calcium, or by modulating second messenger pathways. Purinergic signaling between enteric neurons plays an important role in regulating specific enteric reflexes and overall gastrointestinal function. In the present article, we review evidence for purine receptors in the enteric nervous system, including P1 (adenosine) receptors and P2 (ATP) receptors. We will explore the role they play in mediating fast and slow synaptic transmission and in presynaptic inhibition of transmission. Finally, we will examine the molecular properties of the native receptors, their signaling mechanisms, and their role in gastrointestinal pathology. Keywords

“…receptors (i.e. neuropathic and inflammatory pain, headache pain and migraine) [22,[31][32][33][34][35][36][37][38][39]. As a consequence, targeting these receptors represents an innovative therapeutic strategy to treat both neuropathic and inflammatory pain conditions [40,41].…”

Section: Introductionmentioning

confidence: 99%

2′,3′-O-Substituted ATP derivatives as potent antagonists of purinergic P2X3 receptors and potential analgesic agents

Ben

Marchenkova

Thomas

et al. 2016

Blocking membrane currents evoked by the activation of purinergic P2X3 receptors localized on nociceptive neurons represents a promising strategy for the development of agents useful for the treatment of chronic pain conditions. Among compounds endowed with such antagonistic action, 2′,3′-O-(2,4,6-trinitrophenyl)-ATP (TNP-ATP) is an ATP analogue, whose inhibitory activity on P2X receptors has been previously reported. Based on the results of molecular modelling studies performed with homology models of the P2X3 receptor, novel adenosine nucleotide analogues bearing cycloalkyl or arylalkyl substituents replacing the trinitrophenyl moiety of TNP-ATP were designed and synthesized. These new compounds were functionally evaluated on native P2X3 receptors from mouse trigeminal ganglion (TG) sensory neurons using patch clamp recordings under voltage clamp configuration. Our data show that some of these molecules are potent (nanomolar range) and reversible inhibitors of P2X3 receptors, without any apparent effect on trigeminal GABA A and 5-HT 3 receptors, whose membrane currents were unaffected by the tested compounds.