New Calcitonin Isolated from the Ray, Dasyatis akajei

Abstract

Calcitonin causes hypocalcemia by inhibiting the resorption of calcium from the bone in mammals. Calcitonin has now been isolated from the ultimobranchial gland of a cartilaginous fish, the ray (Dasyatis akajei), and its amino acid has been determined to be H-Cys-Thr-Ser-Leu-Ser-Thr-Cys-Val-Val-Gly-Lys-Ser-Gln-Gln-Leu-His-Lys-Leu-G ln-Asn-Ile-Gln-Arg-Thr-Asp-Val-Gly-Ala-Ala-Thr-Pro-NH2. Although its basic structure is well conserved, the amino acid sequence of ray calcitonin is considerably different from that of other calcitonins sequenced to date. Because the ray lacks calcified bones, an examination of the effect of calcitonin in this fish may elucidate a new role for calcitonin in vertebrates.

Calcitonin: characterisation and expression in a teleost fish, Fugu rubripes

“…These have previously been classified into 5 different lineages according to amino acid sequence similarities. These are the human (human, rabbit, rat), pig (pig, cattle, dog and sheep), bony fish (salmon, eel, goldfish, sardine and chicken), cartilaginous fish (stingray) and amphibian (bullfrog) lineages (Takei et al 1991, Yoshida et al 1997. In the calcitonin tree, the mammals and reptiles/birds branch at similar times but into distinct lineages, with the teleosts branching off later with the primitive fishes basal to the whole grouping.…”

Hormonal Control of Ca Homeostasis in Lower Vertebrates: Considering the Evolution

“…We have so far clarified the primary structure of the calcitonin of the stingray, goldfish, sardine and bullfrog by the purification technique of peptides (Takei et al, 1991;Sasayama et al, 1992 andSuzuki et al, 1994;Yoshida et al, 1997). We have also reported the nucleotide sequence of the calcitonin of 4 species of primitive bony fishes, 6 species of amphibians, and 4 species of reptiles by PCR, RT-PCR and RACE-PCR methods 1999;Sakamoto et al, 1999).…”

Overexpression and Purification of Recombinant Eel Calcitonin and Its Phylogenetic Analysis

“…Extension of the comparison with amino acid sequences of the other nonmammalian vertebrates showed that a greater homology exists with the eel CT sequence than with the other sCT and, to a lesser extent, with the chicken CT, as they differ by 2 and 4 amino acids, respectively (Figure 6). We must note that the 2-aa difference between the sCT IV [29], eel CT (eelCT; [30]), goldfish CT (goldCT; [31]), sardine CT (sardCT; [32]), ray CT (rayCT; [33]), and chicken CT (chicCT; [34]). …”