Crayfish Tail Muscle Research Articles

Comparative studies on AMP-deaminase—VII. Purification and some properties of the enzyme from crayfish Orconectes limosus tail muscle

1. 1. AMP-deaminase from tail muscle of crayfish did not bind to phosphocellulose P-11 at standard conditions as do several vertebrate muscular and nonmuscular enzymes. It is also relatively insensitive to the dialysis against water. 2. 2. Highly purified crayfish deaminase expressed very low specific activity as well as enzyme: substrate affinity when compared with vertebrate muscle deaminases and resembles rather vertebrate extramuscular deaminases. 3. 3. The enzyme was specific to 5′AMP, deaminating to the similar extent adenosine-5′-phosphoramidate. It was strongly activated by KCI and ATP while inorganic phosphate was found to be inhibitory. 4. 4. Crayfish AMP-deaminase, similarly to vertebrate enzymes was inhibited upon dialysis against EDTA. Further dialysis against divalent cations resulted in partial restoration of the activity.

Variation of phosphoadenylates and adenylate energy charge in crayfish (decapoda: astacidae) tail muscle due to habitat differences

1. 1. Phosphoadenylate concentrations (ATP, ADP and AMP) were measured in dorsal tail muscle of five crayfish species collected in four aquatic habitats (pond, artesian spring, stream and cave). 2. 2. Phosphoadenylates and adenylate energy charge ( AEC = (ATP + 1 2 ADP)/(ATP + ADP + AMP)) were not significantly different ( P > 0.05) in crayfish tail muscle from species collected in the different aquatic habitats. 3. 3. Concentrations of tail muscle ATP appear to be associated with behavioral activity. The most active species examined, Cambarus tenebrosus, contained significantly greater amounts of tail muscle ATP ( P < 0.05) than did the least active form, Orconectes australis australis.

Immunofluorescent subcellular localization of some muscle proteins: A comparison between tissue sections and isolated myofibrils

The localization of parvalbumin in fish white muscle and of the calcium binding protein, of arginine kinase and of glycogen phosphorylase in crayfish tail muscle have been investigated by immunofluorescence using isolated myofibrils and muscle sections as starting materials. It is shown that the four proteins appear to be localized on the thin filaments when myofibrils are used as starting material. This result contrasts with previous observations where it appeared that parvalbumin in fish muscle and arginine kinase in crayfish muscle were distributed uniformly within the cell. This discrepancy is discussed in relation to the high solubility of these proteins. In the light of the present knowledge about striated muscles from these two organisms, it seems that the roles of parvalbumin in fish and of the calcium binding protein in crayfish are probably different.

121) - ATPase activities of isolated sarcoplasmic reticulum from crayfish tail muscle

121) - ATPase activities of isolated sarcoplasmic reticulum from crayfish tail muscle

Cellular distribution of sarcoplasmic calcium-binding proteins by immunofluorescence

Specific antibodies against carp paravalbumin, crayfish calcium binding protein and crayfish arginine kinase were used for indirect immunofluorescence localization of the respective proteins. Simultaneous staining of the same muscle sections with human serum containing anti-actin autoantibodies served as a probe to identify the isotropic band. Parvalbumin appears to be evenly distributed in carp white muscle. The crayfish calcium binding protein however shows a distinct localization, in the isotropic band, coincident with the actin staining. Arginine kinase, which has the same molecular weight and is extractible in the same way as the calcium binding protein does not show this distinct localization, but is evenly present in crayfish tail muscle, similarly to parvalbumin. The possible meaning of the different distribution of the two calcium binding proteins is discussed.

Ionic composition and distribution of myogen proteins in the tail muscle of fresh water crayfish

1. 1. The ionic concentrations in the myogen of the fresh water crayfish tail muscle are, in m-moles/kg, 22 for Na, 65 for Cl, 1·1 for Ca, 9·5 for Mg, 42 for K and 41 for P; the first 3 ions are predominantly extracellular and the others intracellular. 2. 2. Several major myogen proteins have been shown; one of them binds most of the calcium present in the myogen and appears to be different from the calcium-binding proteins described so far in muscle.

Regulatory proteins of crayfish tail muscle

Native tropomyosin and fragmented sarcoplasmic reticulum from crayfish tail muscle have been obtained in a pure state. After isoelectric precipitation, the former system yields two biologically active components, troponin and tropomyosin. Troponin binds calcium and can dissociate into three subunits of molecular weight 54 000, 29 000 and 16 000. The tropomyosin monomer has a molecular weight of 40 000. Desensitized actomyosin becomes calcium sensitive in the presence of native tropomyosin or tropomyosin plus troponin. The properties of crayfish fragmented sarcoplasmic reticulum (ATPase activity, calcium binding and uptake, inhibition of actomyosin superprecipitation) are characteristic of a calcium pump. Comparison with the regulatory system of rabbit skeletal muscle reveals many similarities between crayfish and mammalians; indeed crayfish fragmented sarcoplasmic reticulum or native tropomyosin can influence the calcium sensitivity of rabbit actomyosin.

The role of native tropomyosin in the calcium sensitivity of crayfish actomyosin

1. 1. Natural actomyosin extracted from crayfish tail muscle was shown to be ensitive to calcium ions in the presence of Mg ATP at low ionic strenght. The ATPase activity was enhanced by 10 −6 M Ca 2+ by 60 per cent or more at various KCl concentrations. 2. 2. Desensitized actomyosin became sensitive to calcium ions, when native tropomyosin prepared from rabbit or crayfish muscle was added. Crayfish native tropomyosin appeared to be more effective to crayfish actomyosin than to rabbit actomyosin.

Flow birefringence studies of crayfish myosins

1. 1. Flow birefringence properties of crayfish myosin B were remarkably changed on addition of ATP: the birefringence greatly diminished, and the extinction angle strikingly increased at high shear stress. 2. 2. Myosin A or pure myosin from crayfish tail muscle was investigated with flow birefringence technique. Myosin separated from myosin B was homogeneous in molecular length, which was calculated to be 1600 A. 3. 3. Actin could not be extracted from the acetone-treated crayfish muscle, and tropomyosin was obtained instead. 4. 4. From the present study it is suggested that crayfish myosin B preparations consist of dissociable myosin A polymers and myosin A.