• Applied Microscopy
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• v.52
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• pp.9.1-9.5
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• 2022

The compact smooth muscle 10S myosin II is a type of a monomer with folded tail and the heads bending back to interact with each other. This inactivated form is associated with regulatory and enzymatic activities affecting myosin processivity with actin filaments as well as ATPase activity. Phosphorylation by RLC can however, shuttle myosin from the inhibited 10S state to an activated 6S state, dictating the equilibrium. Multiple studies contributed by TEM have provided insights in the structural understanding of the 10S form. However, it is only recently that the true potential of Cryo-EM in deciphering the intramolecular interactions of 10S myosin state has been realized. This has led to an influx of new revelations on the 10S inactivation, unfolding mechanism and association in various diseases. This study reviews the gradual development in the structural interpretation of 10S species from TEM to Cryo-EM era. Furthermore, we discuss the utility of Cryo-EM in future myosin 10S studies and its contribution to human health.

• Journal of Life Science
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• v.9 no.6
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• pp.646-652
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• 1999

The effect of temperature on the structure change of the SH of myosin head have been investigated with improved resolution by x-ray diffraction using synchrotron radiation. The movement of myosin head and conformational change of contractile molecules were occurred in the muscle contraction. IASL (iodo acetamide) and MSL (maleimide) disordered the orderly helix arrangement of myosin in the rest state of spin level. The temperature effect on the structure change was great at the UL in the equatorial reflection. But those of IASL and MSL were minor. Equatorial reflection (10, 11) change inferred that myosin head was moved to the vicinity of actin filament by temperature change (from $25^{\circ}C$ to $0^{\circ}C$) at UL, but spin level was not changed. The intensity change of 143 $\AA$ and 72 $\AA$ could offer information of the mass profection of population of myosin heads along the filament axis. The slope of intensity profile of the mass profection of 143$\AA$ and reflection of MSL is appeared sharply and those of UL and IASL were not changed. The decrease of MSL actin reflection at 51 $\AA$ and 59 $\AA$ in the actin reflection change refers that the shifted myosin head binds a certain actin or changes an actin structure. From these results, we could conclude that IASL and MSL were spin labeled on SH of myosin head and disordered the helix arrangement of actin.

• Journal of Veterinary Clinics
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• v.32 no.1
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• pp.62-68
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• 2015

There is no reliable indicator available for the diagnosis of horse laminitis, although the disease is common and costly. This study was performed to develop a specific diagnostic biomarker for laminitis. We have identified 33 differentially expressed proteins in plasma of a horse suffering laminitis that is experimentally induced by an overdose of oligofructose, in comparison with normal horse plasma. Among the proteins, myosin-9 mRNA was found in RNA sequencing analysis to be expressed specifically in laminitis tissues compared to other horse tissues. It is thus suggested that expression of plasma myosin-9 may be used for the diagnosis of equine laminitis.

• Asian-Australasian Journal of Animal Sciences
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• v.16 no.9
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• pp.1384-1389
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• 2003

In order to clarify one of the biological functions of pork, we investigated whether a peptic hydrolysate of denatured porcine crude myosin showed inhibitory activity against angiotensin I-converting enzyme (ACE), which contributed to hypertension. Our results indicated that this hydrolysate showed relatively strong activity, and we therefore attempted to separate the involved peptides, which were considered to be active substances. To isolate these active peptides, the hydrolysate was separated using a solidphase separation, gel filtration high-performance liquid chromatography (HPLC), and two kinds of reverse phase HPLC. In each stage of separation, many fractions were detected, almost all of which showed ACE inhibitory activity. Thus, we suggested that the activity of the hydrolysate as a whole was a result of the activities of the many individual peptides. Six peaks were distinguished, with yields from 34 to 596 ppm of original crude myosin. In addition to the six peaks, many other active fractions were found throughout the separation steps, strongly suggesting that whole porcine crude myosin itself had ACE inhibitory activity. Moreover, pork as food was considered to function as an ACE inhibitory material in vivo, because pork proteins consist primarily of crude myosin, which included almost all the myofibrillar structural proteins.

• Korean Journal of Food Science and Technology
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• v.30 no.4
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• pp.862-870
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• 1998

This study shows the application of Ci-ELISA method for monitoring the denaturation of myosin by the frozen treatment in order to differentiate thawed beef from chilled. Hanwoo M.Semitendinosus (n=25) was treated under the two different frozen process as follows; simple frozen treatment (Exp-1) at 4 different temperatures, -10, -20, -50 and $-80^{\circ}C$, respectively, and repeated thawing-refreezing treatment (Exp-2) stored at 4 different temperatures, -10, -20, -50 and $-80^{\circ}C$, respectively. Antibodies (Abs) were produced from rabbits immunized with myosin whole molecule (MWM) isolated from beef round, heavy meromyosin S-1 (S-1) and light meromyosin (LMM) prepared by digestion of MWM. Each immunoglobulin G (IgG) was separated from antiserum. At 6 month storage, IA of anti-MWM IgG for myosin was decreased to 32.67, 32. 23, 51.52 and 34.27% in Exp-1 and to 14.82, 15.61, 25.3 and 23.7% in Exp-2 at -10, -20, -50 and $-80^{\circ}C$, respectively (P<0.05). In Exp-1, the reactivities of anti-LMM IgG were decreased to 25.12, 21.42, 49.05 and 28.96%, and those of Exp-2 were to 11.88, 9.56, 20.63 and 12.64% at -10, -20, -50 and $-80^{\circ}C$, respectively, at 6 times thawing (P<0.05). Conclusively, myosin was denaturated by freezing treatment and LMM or myosin rod part might have suffered from more extreme demage than HMM S-1, and samples at $-50^{\circ}C$ were slightly injured less than others by freezing treatment.

• International Journal of Industrial Entomology and Biomaterials
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• v.9 no.1
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• pp.127-130
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• 2004

We describe here the cloning and characterization of a cDNA encoding a putative myosin light chain-2 (MLC-2) from the mole cricket, Gryllotalpa orientalis. The G. orientalis MLC-2 cDNA sequences comprised of 615 bp with 205 amino acid residues with a calculated molecular weight of approximately 23 kDa. The deduced protein sequence of G. orientalis MLC-2 cDNA showed 64% and 54% identity to Drosophila melanogaster MLC-2 and D. yakuba MLC-2, respectively. Northern blot analysis confirmed the muscle-specific expression of G. orientalis MLC-2.

• Journal of the Korean Applied Science and Technology
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• v.24 no.4
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• pp.362-368
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• 2007

To study the relationship between elementary biochemical states and structural states of the actomyosin crossbridges in muscle, the effects of binding of MgADP to myosin heads in the rigor muscle were examined by X-ray diffraction using synchrotron radiation. X-ray diffraction studies have been made to investigate the effects of binding of ADP on the structure of glycerinated rabbit skeletal muscle in the rigor state. The intensity increase was accompanied by a slight but distinct decrease in the 5.9 am layer-line intensity close to the meridian. These results strongly suggest that myosin heads altered their attached conformation in the proximal end toward the plane perpendicular to the fiber axis when MgADP was bound to them. We found that the intensity of the 14.5 nm-based meridional reflections increase by 20-50% when MgADP was added to the rigor muscle in the presence of hexokinase and myokinase inhibitor.

• Asian-Australasian Journal of Animal Sciences
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• v.21 no.12
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• pp.1703-1709
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• 2008

As genetic markers, single nucleotide polymorphisms (SNP) are very appropriate for the development of genetic tests for economic traits in livestock. Several microsatellite markers have been identified as useful markers for the genetic improvement of Hanwoo. Among those markers, ILSTS035 was recently mapped at a similar position with four SNPs (AH1_11, AH1_9, 31465_446, and 12273_165) in a linkage map of EST-based SNP in BAT6. Among the four SNPs, two SNPs (31465_446 and 12273_165) were analyzed using BLAST at the NCBI web site. The sequences including the 12273_165 SNP were identified at the intron region within the LOC534614 gene on the gene sequence map (Bos taurus NCBI Map view, build 3.1). The LOC534614 gene represents a protein similar to myosin heavy chain, fat skeletal muscle, embryonic isoform 1 in the dog, and myosin_1 (Myosin heavy chain D) in Macaca mulatta. In cattle, the myosin heavy chain was associated with muscle development. The phenotypic data for growth and carcass traits in the 415 animals were analyzed by the mixed ANCOVA (analysis of covariance) linear model using PROC GLM module in SAS v9.1. By the genotyping of Hanwoo individuals (n = 415) to evaluate the association of SNP with growth and carcass traits, it was shown that the 12273_165 SNP region within LOC534614 may be a candidate marker for growth. The results of the statistical analyses suggested that the genotype of the 12273_165 SNP significantly affected birth weight, weight of the cattle at 24 months of age, average daily gain and carcass cold weight (p<0.05). Consequently, the 12273_165 SNP polymorphisms at the LOC534614 gene may be associated with growth in Hanwoo, and functional validation of polymorphisms in LOC534614 should be performed in the future.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.5 no.2
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• pp.57-62
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• 1972

Natural actomyosin was extracted from the dorsal muscle of carp (Cyprinus carpio), and some Physico-chemical properties were determined. The sedimentation constant ($s_{20},\;_\omega$) of the purified skeletal muscle actomyosin was about 24.76s and the ATP sensitivity 147-176. The specific viscosity was rapidly ascended with the increase of protein concentration as other vertebrate actomyosins. ATPase activating site under the effect of pH variation was showed on the both sides of acid and base resembling with the tendency of rabbit skeletal muscle actomyosin, and found at 6.0 on the acidic side and at 9.5 on the basic side.

• Journal of Life Science
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• v.21 no.8
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• pp.1076-1082
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• 2011

Microtubule-based kinesin motor proteins are used for long-range vesicular transport. KIF5s (KIF5A, KIF5B and KIF5C) mediate the transport of various membranous vesicles along microtubules, but the mechanism behind how they recognize and bind to a specific cargo has not yet been completely elucidated. To identify the interaction protein for KIF5B, yeast two-hybrid screening was performed and a specific interaction with the unconventional myosin Myo9b, an actin-based vesicle transport motor, was found. The GTPase-activating protein (GAP) domain of Myo9s was essential for interaction with KIF5B in the yeast two-hybrid assay. Myo9b bound to the carboxyl-terminal region of KIF5B and to other KIF5 members. In addition, glutathione S-transferase (GST) pull-downs showed that Myo9s specifically interact to the complete Kinesin-I complex. An antibody to KIF5B specifically co-immunoprecipitated KIF5B associated with Myo9s from mouse brain extracts. These results suggest that kinesin-I motor protein interacts directly with actin-based motor proteins in the cell.