cDNA cloning of myosin rod and the complete primary structure of myosin heavy chain of walleye pollack fast skeletal muscle

Abstract

SUMMARY: The amino acid sequences of myosin rod containing subfragment‐2 (S2) and light meromyosin (LMM) were determined by cDNA cloning for walleye pollack fast skeletal myosin heavy chain. While S2 and LMM were composed of 442 and 656 amino acid residues, a total of 1937 amino acid residues accounted for the whole myosin heavy chain molecule with previously determined sequence for the subfragment‐1 heavy chain region of this fish. Both regions for S2 and LMM showed a seven‐residue repeat pattern characteristic to fibrous proteins with a coiled‐coil structure of two α‐helices, displaying a, b, c, d, e, f, and g where positions a and d were frequently occupied by hydrophobic amino acids and c and g often contained charged residues. The occurrence of a 28‐residue unit with repetitive sequence was also strongly suggested, when one and three skip residues were adopted into S2 and LMM, respectively. Thus, walleye pollack S2 and LMM consisted of 17 and 24 zones with a 28‐residue repeat rearrangement. There were several amino acid substitutions which might account for a low thermal stability of walleye pollack myosin heavy chain in comparison with the sequences of higher vertebrate counterparts. However, it seemed difficult to interpret such low stability only from the comparison in the 28‐residue repeat arrangement at the primary structure.

cDNA cloning and complete primary structures of myosin heavy chains from brushtooth lizardfishSaurida undosquamisand wanieso lizardfishS. waniesofast skeletal muscles

“…The comparison of deduced amino acid sequences of brushtooth and wanieso lizardfish MYH with those of other sequences is presented in Table 4. The highest sequence identity of bMYH3 was 97% to wMYH1, followed by MYH from white croaker 6 (AB039672), walleye pollack 11,12 (AB017819 and AB000214), carp acclimated to 10°C 21,22 (D89990) and rabbit (U32574) in the decreasing order. Brushtooth and wanieso lizardfish MYH showed the amino acid sequence identity of 92–93% to white croaker MYH, which was higher than that of 90% to walleye pollack MYH.…”

“…Despite very high amino acid sequence identity between MYH of the above two fish species, 10–13 the corresponding myosins showed striking differences in polymer‐forming ability, viscoelasticity and thermodynamic properties possibly caused by species‐specific substitutions of some particular amino acids 7–9 . Three myosin fragments of white croaker, S1, S2 and LMM, exhibited 79–94% sequence identities to the corresponding fragments of various vertebrates, including walleye pollack.…”

“…Although walleye pollack Theragra chalcogramma is the much more popular fish for surimi production, it is inferior to white croaker in terms of thermal stability and gelation property. To elucidate the molecular basis of such differences between myosins of the two species, a series of investigations have been carried out focusing on their primary structure and physicochemical properties 10–13 …”

“…Three myosin fragments of white croaker, S1, S2 and LMM, exhibited 79–94% sequence identities to the corresponding fragments of various vertebrates, including walleye pollack. Furthermore, the differences in myosin gel formation between walleye pollack and white croaker were attributed to the species‐specific structural properties of LMM region 6,7,12,13 . Site‐directed mutagenesis revealed that cysteine at position 525 of white croaker LMM is responsible for polymer formation through construction of disulfide‐bridge 7 …”

Three embryonic myosin heavy chain genes encoding different motor domain structures from common carp show distinct expression patterns in cranial muscles

“…3), confirmed that common carp embryonic MYH emb1 and MYH emb2 both belong to a fast type, whereas MYH emb3 does to a slow/cardiac type. MYH emb1 and MYH emb2 formed a monophyletic clade with zebrafish myhz2 and myhc4 (Xu et al, 2000;Peng et al, 2002;Nihei et al, 2006), and these MYHs formed one group with brushtooth lizardfish MYH Su Fast (Hossain et al, 2008), wanieso lizardfish MYH Sw Fast (Hossain et al, 2008), chum salmon MYH Ok Fast (Ojima et al, 1998), walleye pollack MYH Tc Fast (Togashi et al, 2000), yellowbelly rockcod MYH Nc fast (Gauvry et al, 2000), torafugu MYH M743-2 (Ikeda et al, 2004;Ikeda et al, 2007) and white croaker MYH Pa Fast (Yoon et al, 2000) (see Fig. 3).…”