Comparative genomics provides evidence for close evolutionary relationships between the urotensin II and somatostatin gene families - PubMed (original) (raw)

Comparative Study

. 2006 Feb 14;103(7):2237-42.

doi: 10.1073/pnas.0510700103. Epub 2006 Feb 7.

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Comparative Study

Comparative genomics provides evidence for close evolutionary relationships between the urotensin II and somatostatin gene families

Hervé Tostivint et al. Proc Natl Acad Sci U S A. 2006.

Abstract

Although urotensin II (UII) and somatostatin 1 (SS1) exhibit some structural similarities, their precursors do not show any appreciable sequence identity and, thus, it is widely accepted that the UII and SS1 genes do not derive from a common ancestral gene. The recent characterization of novel isoforms of these two peptides, namely urotensin II-related peptide (URP) and somatostatin 2 (SS2)/cortistatin (CST), provides new opportunity to revisit the phylogenetic relationships of UII and SS1 using a comparative genomics approach. In the present study, by radiation hybrid mapping and in silico sequence analysis, we have determined the chromosomal localization of the genes encoding UII- and somatostatin-related peptides in several vertebrate species, including human, chicken, and zebrafish. In most of the species investigated, the UII and URP genes are closely linked to the SS2/CST and SS1 genes, respectively. We also found that the UII-SS2/CST locus and the URP/SS1 locus are paralogous. Taken together, these data indicate that the UII and URP genes, on the one hand, and the SS1 and SS2/CST genes, on the other hand, arose through a segmental duplication of two ancestral genes that were already physically linked to each other. Our results also suggest that these two genes arose themselves through a tandem duplication of a single ancestral gene. It thus appears that the genes encoding UII- and somatostatin-related peptides belong to the same superfamily.

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Conflict of interest statement

Conflict of interest statement: No conflicts declared.

Figures

Fig. 1.

Fig. 1.

Comparison of the amino acid sequences and predicted secondary structures of human UII, URP, SS1, and CST. Common residues are indicated in bold characters.

Fig. 2.

Fig. 2.

Alignment of the amino acid sequences of chicken and zebrafish UII-related peptide precursors characterized in the present study. The sequences of mature peptides are indicated in boldface. Dashes indicate gaps. All of these sequences have been deposited in the GenBank database [accession nos. NM_212848 (prepro-urotensin II-α, zebrafish); NM_205591 (prepro-urotensin II-β, zebrafish); NM_206990 (prepro-urotensin II, chicken); and NM_206989 (prepro-urotensin II-related peptide, chicken)].

Fig. 3.

Fig. 3.

Phylogenetic tree of the UII gene family. An alignment of UII-related peptide precursor sequences currently known in vertebrates (data not shown) was used to calculate a neighbor-joining distance unrooted tree (33), using the

phylo_win

program (32). The values above the branches are the results (in percentages) of the bootstrap analysis.

Fig. 4.

Fig. 4.

Map showing chromosomal position of UII- and somatostatin-related peptide encoding genes in human. Other putative duplicated gene pairs localized in their vicinity are indicated. The duplicates of each pair are connected by broken line. All of the positions are expressed in megabases. CLCN2/6, chloride channel 2/6; MASP1/2, mannose-binding lectin-associated serine protease 1/2; TP73/73L, tumor protein p73/p73-like; DFFA/B, DNA fragmentation factor A/B; TNFRSF1B/8/9/25, tumor necrosis factor receptor superfamily member 1B/8/9/25; FBX2/6/44, F-box protein 2/6/44; NPPA/NPPB, A/B-type natriuretic peptide precursor; TML7, transmembrane protein 7; IF28, 28-kDa IFN-responsive protein; CLDN1/16, claudin 1/16.

Fig. 5.

Fig. 5.

Proposed evolutionary history of the somatostatin/UII gene family. According to this scenario, UII- and somatostatin-related peptide genes would result from two rounds of gene duplication; i.e., a tandem duplication followed by a segmental duplication. The latter duplication event may coincide with one of the two whole-genome duplications that took place during vertebrate evolution.

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References

    1. Pearson D., Shively J. E., Clark B. R., Geschwind I. I., Barkley M., Nishioka R. S., Bern H. A. Proc. Natl. Acad. Sci. USA. 1980;77:5021–5024. - PMC - PubMed
    1. Conlon J. M., O’Harte F., Smith D. D., Tonon M. C., Vaudry H. Biochem. Biophys. Res. Commun. 1992;188:578–583. - PubMed
    1. Conlon J. M., Tostivint H., Vaudry H. Regul. Pept. 1997;69:95–103. - PubMed
    1. Coulouarn Y., Lihrmann I., Jegou S., Anouar Y., Tostivint H., Beauvillain J. C., Conlon J. M., Bern H. A., Vaudry H. Proc. Natl. Acad. Sci. USA. 1998;95:15803–15808. - PMC - PubMed
    1. Coulouarn Y., Jégou S., Tostivint H., Vaudry H., Lihrmann I. FEBS Lett. 1999;457:28–32. - PubMed

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