Identification of a novel adrenomedullin gene family in teleost fish.
Adrenomedullin (AM) is a multifunctional peptide known to form a hormone family with calcitonin gene-related peptide (CGRP) and amylin. We have cloned five distinct AM cDNAs from the pufferfish, Takifugu rubripes, and named them TrAM-1, -2, -3, -4, and -5. Judging from the deduced precursor sequences and processing pattern of the C-terminal mature peptides, TrAMs may be divided into at least two groups; AM-2 and -3, and AM-1, -4, and possibly -5. Phylogenetic analysis of the mature peptides, exon-intron structure of their genes, and tissue distribution of their mRNA also support this classification. TrAM-1 and -4 were ubiquitously expressed in various tissues including the kidney and interrenal (adrenal homolog) as in the case of mammalian AM, while TrAM-2 and -3 were expressed most abundantly in the brain followed by the vascular tissues. Synteny of the genes around AM gene showed that TrAM-1 is the ortholog of mammalian AM. The presence of a PAMP-like sequence in the prosegment of TrAM-1 also supports this notion. Multiple AMs were also detected in another pufferfish, Tetraodon nigroviridis, and in zebrafish, Danio rerio. The present study shows for the first time the presence of a novel AM family in teleost fish that is independent from CGRP and amylin, which further suggests the possible existence of multiple AMs in mammals.
Ogoshi
Maho
M
Ocean Research Institute, The University of Tokyo, Nakano, 164-8639, Tokyo, Japan. ogoshi@ori.u-tokyo.ac.jp
Inoue
Koji
K
Takei
Yoshio
Y
D053607:Adrenomedullin; D000595:Amino Acid Sequence; D000818:Animals; D003001:Cloning, Molecular; D017124:Conserved Sequence; D019143:Evolution, Molecular; D005399:Fishes / Q000235:genetics / Q000378:metabolism; D020869:Gene Expression Profiling / Q000379:methods*; D005786:Gene Expression Regulation / Q000502:physiology; D008969:Molecular Sequence Data; D010455:Peptides / Q000145:classification / Q000235:genetics* / Q000378:metabolism*; D017385:Sequence Homology; D013045:Species Specificity; D023741:Takifugu / Q000235:genetics* / Q000378:metabolism*; D014018:Tissue Distribution; D014714:Vertebrates / Q000235:genetics / Q000378:metabolism
D010455:Peptides; D053607:Adrenomedullin