Urotensin II receptor (UTR) exists in hyaline chondrocytes: A study of peripheral distribution of UTR in the African clawed frog, Xenopus laevis

International Union of Basic and Clinical Pharmacology. XCII. Urotensin II, Urotensin II–Related Peptide, and Their Receptor: From Structure to Function

“…In zebrafish, URP mRNA is primarily localized in motoneurons of the brainstem and spinal cord (submitted manuscript), as previously reported in tetrapods (Coulouarn et al, 1998(Coulouarn et al, , 1999Dubessy et al, 2008;Konno et al, 2013), indicating that the expression pattern of the URP gene has been strongly conserved during vertebrate evolution. In contrast, the expression patterns of the URP1 and URP2 genes differ markedly from that of the URP gene.…”

“…As mentioned above (see section II.A), UII was initially discovered in teleosts (Pearson et al, 1980) and subsequently characterized in amphibians (Conlon et al, 1992b) and mammals (Coulouarn et al, 1998(Coulouarn et al, , 1999. Conversely, URP was first identified in mammals (Sugo et al, 2003) and later in birds and amphibians (Konno et al, 2013). Hence, it was logical to search for the existence of URP in fish.…”

“…The primary structure of URP is highly similar to that of the C-terminal octapeptide region of UII. The sequence of URP has now been determined in representative species of teleost fish (Quan et al, 2012), amphibians (Konno et al, 2013), birds , and mammals , and it appears that the structure of the peptide has been strongly preserved during vertebrate evolution . As for UII, the sequence of the cyclic hexapeptide of URP is identical in all species investigated so far ( Fig.…”

MOLECULAR EVOLUTION OF GPCRS: Somatostatin/urotensin II receptors

“…The cDNA encoding its precursor was cloned in rats, mice, and humans (Sugo et al 2003) and then in chickens ) and the African clawed frog (Xenopus laevis; Konno et al 2013). The URP gene has previously been thought to exist only in tetrapods, but its occurrence in teleosts has been demonstrated recently (Quan et al 2012).…”

“…Notably, UII mRNA is detected early in the formation of the rat embryonic ventral neural tube, at a developmental stage coincident with the differentiation of motor neurons (Coulouarn et al 2001). Recent studies indicate that this motoneuronal expression pattern is conserved for both UII and URP in the African clawed frog (Xenopus laevis; Konno et al 2013). The presence of UII receptor on cholinergic nerve terminals, in part originating from the recurrent motoneuron axon collaterals, in mouse spinal cord has given rise to the idea that UII may regulate motoneuron activity in an autocrine/paracrine manner (Bruzzone et al 2010).…”