サカサナマズの耳石基質蛋白質の解析

It has been previously suggested that the calcium density of the otolith in upside-down swimming Synodontis nigriventris is lower than that in upside-up swimming Synodontis multipunctatus. In the present study, EDTA-soluble matrix proteins of otolith in the utricle of the catfish (S. nigriventris, S. multipunctatus and upside-up swimming Synodontis brichadi) and goldfish (Carassius auratus) were examined. Two main bands (about 55 kD and 80 kD) with SDS-PAGE in the 3 species of the catfish were detected. In contrast, goldfish had the about 55 kD band alone. The band of about 80 kD was consisted of two sub-bands. A lighter and a heavier band were observed in S. brichadi and S. nigriventris, respectively. S. multipunctatus had the two bands. Mass spectrometric analysis showed there are some proteins of molecular weight under 14 kD. The molecular weights of the proteins were different among the fishes. These results suggest that the different kind of matrix protein may result in different degree of calcification in otolith formation between the upside-down swimming catfish and upside-up swimming catfish.
資料番号: AA0045438013