title: Translational Repression of a Splice Variant of Cynomolgus Macaque CXCL1L by Its C-Terminal Sequence.
abstract: We previously isolated a cDNA clone from cynomolgus macaque encoding a novel CXC chemokine that we termed CXCL1L from its close similarity to CXCL1. However, the cDNA consisted of 3 exons instead of 4 exons that were typically seen in other CXC chemokines. Here, we isolated a cDNA encoding the full-length variant of CXCL1L that we termed CXCL1Lβ. CXCL1Lβ is 50 amino acids longer than the original CXCL1L, which we now term CXCL1Lα. The CXCL1Lβ mRNA is much more abundantly expressed in the cynomolgus macaque tissues than CXCL1Lα mRNA. However, CXCL1Lβ protein was poorly produced by transfected cells compared with that of CXCL1Lα. When the coding region of the fourth exon was fused to the C-terminus of CXCL1 or even to a nonsecretory protein firefly luciferase, the fused proteins were also barely produced, although the mRNAs were abundantly expressed. The polysome profiling analysis suggested that the inhibition was mainly at the translational level. Furthermore, we demonstrated that the C-terminal 5 amino acids of CXCL1Lβ were critical for the translational repression. The present study, thus, reveals a unique translational regulation controlling the production of a splicing variant of CXCL1L. Since the CXCL1L gene is functional only in the Old World monkeys, we also discuss possible reasons for the conservation of the active CXCL1L gene in these monkeys during the primate evolution.
authors.affiliation: 1 Department of Molecular Enzymology, Kumamoto University Graduate School of Medical Sciences , Kumamoto, Japan .
authors.forename: Hisayuki
authors.initials: H
authors.lastname: Nomiyama
authors.affiliation: 2 Division of Bioengineering and Bioinformatics, Graduate School of Information Science and Technology, Hokkaido University , Sapporo, Japan .
authors.forename: Naoki
authors.initials: N
authors.lastname: Osada
authors.affiliation: 3 Tsukuba Primate Research Center, National Institute of Biomedical Innovation , Health and Nutrition (NIBIOHN), Tsukuba, Japan .
authors.forename: Ichiro
authors.initials: I
authors.lastname: Takahashi
authors.affiliation: 3 Tsukuba Primate Research Center, National Institute of Biomedical Innovation , Health and Nutrition (NIBIOHN), Tsukuba, Japan .
authors.forename: Keiji
authors.initials: K
authors.lastname: Terao
authors.affiliation: 4 Department of Medical Biochemistry, Faculty of Life Sciences, Kumamoto University , Kumamoto, Japan .
authors.forename: Kazuya
authors.initials: K
authors.lastname: Yamagata
authors.affiliation: 5 The Health and Kampo Institute , Sendai, Japan .
authors.forename: Osamu
authors.initials: O
authors.lastname: Yoshie
mesh_terms: D017398:Alternative Splicing; D000595:Amino Acid Sequence; D000818:Animals; D002478:Cells, Cultured; D054360:Chemokine CXCL1 / Q000737:chemistry / Q000145:classification / Q000235:genetics* / Q000378:metabolism; D018076:DNA, Complementary / Q000235:genetics; D005786:Gene Expression Regulation; D008252:Macaca fascicularis; D010802:Phylogeny; D014176:Protein Biosynthesis; D054730:Protein Interaction Domains and Motifs / Q000235:genetics; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism
chemical_list: D054360:Chemokine CXCL1; D018076:DNA, Complementary; D012333:RNA, Messenger
keywords: CXCL1L; Old World monkeys; chemokine; cynomolgus macaque; evolution; gene duplication; translational regulation