TY - JOUR
T1 - Molecular cloning of prepro-thyrotropin-releasing hormone cDNAs from the common carp Cyprinus carpio and goldfish Carassius auratus
AU - Aoki, Yasuhiro
AU - Takahashi, Miho
AU - Masuda, Tomohiro
AU - Tsukamoto, Toshiro
AU - Iigo, Masayuki
AU - Yanagisawa, Tadashi
N1 - Funding Information:
We express our thanks to Ms. Asami Matsumoto and Mr. Takuya Aoki for their technical assistance. We are grateful to Professor Katsumi Aida for access to his laboratory and equipment. This study was supported in part by Grants-in-Aid for the Scientific Research from the Ministry of Education, Culture, Sports, Science and Technology of Japan and Japan society for the Promotion of Science (JSPS). T.M. is supported individually by a JSPS Research Fellowship for Young Scientists.
PY - 2005/3
Y1 - 2005/3
N2 - To expand our knowledge on the evolution of prepro-thyrotropin-releasing hormone (ppTRH) from fish to tetrapods, sequences of ppTRH cDNAs from two cyprinid teleosts, the common carp Cyprinus carpio and goldfish Carassius auratus, were determined. Degenerate primers were designed based on the conserved regions between the zebrafish ppTRH sequence identified from the zebrafish EST database and the sockeye salmon ppTRH sequence, and PCR amplification was performed. Full-length ppTRHs were confirmed from ppTRH cDNAs obtained by 5′- and 3′-rapid amplification of cDNA ends. The common carp ppTRH cDNA encodes 187 amino acids including 6 copies of the TRH progenitor sequence (Lys/Arg-Arg-Gln-His-Pro-Gly-Lys/Arg-Arg), whereas the goldfish ppTRH cDNA encodes 231 amino acids including 8 copies of the TRH progenitor sequence. The molecular phylogenetic analysis of the ppTRH sequences reflected the predicted pattern of species classification. The common carp, goldfish, and zebrafish ppTRHs have some unique characteristics. The common carp and zebrafish ppTRHs are smaller than that of the goldfish mainly due to the absence of 29 and 17 consecutive amino acids, respectively. The deleted region includes one or two TRH progenitor sequences flanked by some glutamate residues, similar to the glutamate-rich regions of human ppTRH. Hydropathy profiles showed that the presence of a TRH progenitor sequence in the C-terminal hydrophilic region is a characteristic of teleosts and human ppTRHs. These observations may provide clues to a better understanding of the molecular evolution of ppTRH.
AB - To expand our knowledge on the evolution of prepro-thyrotropin-releasing hormone (ppTRH) from fish to tetrapods, sequences of ppTRH cDNAs from two cyprinid teleosts, the common carp Cyprinus carpio and goldfish Carassius auratus, were determined. Degenerate primers were designed based on the conserved regions between the zebrafish ppTRH sequence identified from the zebrafish EST database and the sockeye salmon ppTRH sequence, and PCR amplification was performed. Full-length ppTRHs were confirmed from ppTRH cDNAs obtained by 5′- and 3′-rapid amplification of cDNA ends. The common carp ppTRH cDNA encodes 187 amino acids including 6 copies of the TRH progenitor sequence (Lys/Arg-Arg-Gln-His-Pro-Gly-Lys/Arg-Arg), whereas the goldfish ppTRH cDNA encodes 231 amino acids including 8 copies of the TRH progenitor sequence. The molecular phylogenetic analysis of the ppTRH sequences reflected the predicted pattern of species classification. The common carp, goldfish, and zebrafish ppTRHs have some unique characteristics. The common carp and zebrafish ppTRHs are smaller than that of the goldfish mainly due to the absence of 29 and 17 consecutive amino acids, respectively. The deleted region includes one or two TRH progenitor sequences flanked by some glutamate residues, similar to the glutamate-rich regions of human ppTRH. Hydropathy profiles showed that the presence of a TRH progenitor sequence in the C-terminal hydrophilic region is a characteristic of teleosts and human ppTRHs. These observations may provide clues to a better understanding of the molecular evolution of ppTRH.
KW - Common carp
KW - Goldfish
KW - Molecular evolution
KW - Prepro-thyrotropin-releasing hormone
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U2 - 10.1016/j.ygcen.2004.11.011
DO - 10.1016/j.ygcen.2004.11.011
M3 - Article
C2 - 15707606
AN - SCOPUS:13544266410
SN - 0016-6480
VL - 141
SP - 84
EP - 92
JO - General and Comparative Endocrinology
JF - General and Comparative Endocrinology
IS - 1
ER -