The yeast type II myosin heavy chain: Analysis of its predicted polypeptide sequence

1991 ◽  
Vol 12 (1) ◽  
pp. 61-68 ◽  
Author(s):  
Frank P. Sweeney ◽  
Michael J. Pocklington ◽  
Elisha Orr
Keyword(s):  
Myosin Heavy Chain ◽  
Heavy Chain ◽  
Type Ii ◽  
Chain Analysis ◽  
Polypeptide Sequence ◽  
Type Ii Myosin

Relationships between maximal strength, muscle size, and myosin heavy chain isoform composition and postactivation potentiation

2016 ◽  
Vol 41 (5) ◽  
pp. 491-497 ◽  
Author(s):  
Laurent B. Seitz ◽  
Gabriel S. Trajano ◽  
G. Gregory Haff ◽  
Charles C.L.S. Dumke ◽  
James J. Tufano ◽  
...  
Keyword(s):  
Skeletal Muscle ◽  
Myosin Heavy Chain ◽  
Heavy Chain ◽  
Human Skeletal Muscle ◽  
Knee Extensor ◽  
Type Ii ◽  
Postactivation Potentiation ◽  
Test Protocol ◽  
Extensor Torque ◽  
Type Ii Myosin

The purpose of this study was to examine the relationships between maximal voluntary postactivation potentiation (PAP) and maximal knee extensor torque, quadriceps cross-sectional area (CSA) and volume, and type II myosin heavy chain (MHC) isoform percentage in human skeletal muscle. Thirteen resistance-trained men completed a test protocol consisting of 2 isokinetic knee extensions at 180°·s–1 performed before and 1, 4, 7, and 10 min after the completion of 4 maximal knee extensions at 60°·s–1 (i.e., a conditioning activity (CA)). Magnetic resonance imaging and muscle microbiopsy procedures were completed on separate days to assess quadriceps CSA and volume and MHC isoform content. Maximal voluntary PAP response was assessed as the ratio of the highest knee extensor torques measured before and after the CA. There were large to very large correlations between maximal voluntary PAP response and maximal knee extensor torque (r = 0.62) and quadriceps CSA (r = 0.68) and volume (r = 0.63). Nonetheless, these correlations were not statistically significant after adjusting for the influence of type II MHC percentage using partial correlation analysis. By contrast, the strongest correlation was observed for type II MHC percentage (r = 0.77), and this correlation remained significant after adjusting for the other variables. Maximal voluntary PAP response is strongly correlated with maximal knee extensor torque and quadriceps CSA and volume, but is mostly clearly associated with the type II myosin isoform percentage in human skeletal muscle.

scholarly journals Type II Myosin Heavy Chain Encoded by the myo2 Gene Composes the Contractile Ring during Cytokinesis in Schizosaccharomyces pombe

1997 ◽  
Vol 137 (6) ◽  
pp. 1309-1319 ◽  
Author(s):  
Chikako Kitayama ◽  
Asako Sugimoto ◽  
Masayuki Yamamoto
Keyword(s):  
Schizosaccharomyces Pombe ◽  
Myosin Heavy Chain ◽  
Heavy Chain ◽  
Coiled Coil ◽  
Yeast Cells ◽  
Type Ii ◽  
Contractile Ring ◽  
Iq Motif ◽  
Multinucleated Cells ◽  
Type Ii Myosin

We cloned the myo2 gene of Schizosaccharomyces pombe, which encodes a type II myosin heavy chain, by virtue of its ability to promote diploidization in fission yeast cells. The myo2 gene encodes 1,526 amino acids in a single open reading frame. Myo2p shows homology to the head domains and the coiledcoil tail of the conventional type II myosin heavy chain and carries putative binding sites for ATP and actin. It also carries the IQ motif, which is a presumed binding site for the myosin light chain. However, Myo2p apparently carries only one IQ motif, while its counterparts in other species have two. There are nine proline residues, which should break α-helix, in the COOH-terminal coiled-coil region of Myo2p. Thus, Myo2p is rather unusual as a type II myosin heavy chain. Disruption of myo2 inhibited cell proliferation. myo2Δ cells showed normal punctate distribution of interphase actin, but they produced irregular actin rings and septa and were impaired in cell separation. Overproduction of Myo2p was also lethal, apparently blocking actin relocation. Nuclear division proceeded without actin ring formation and cytokinesis in cells overexpressing Myo2p, giving rise to multinucleated cells with dumbbell morphology. Analysis using tagged Myo2p revealed that Myo2p colocalizes with actin in the contractile ring, suggesting that Myo2p is a component of the ring and responsible for its contraction. Furthermore, genetic evidence suggested that the acto–myosin system may interact with the Ras pathway, which regulates mating and the maintenance of cell morphology in S. pombe.

Type II myosin regulatory light chain relieves auto-inhibition of myosin-heavy-chain function

2000 ◽  
Vol 2 (11) ◽  
pp. 855-858 ◽  
Author(s):  
Naweed I. Naqvi ◽  
Kelvin C. Y. Wong ◽  
Xie Tang ◽  
Mohan K. Balasubramanian
Keyword(s):  
Myosin Heavy Chain ◽  
Heavy Chain ◽  
Light Chain ◽  
Regulatory Light Chain ◽  
Myosin Regulatory Light Chain ◽  
Type Ii ◽  
Type Ii Myosin

Identification of Myo3, a second type-II myosin heavy chain in the fission yeast Schizosaccharomyces pombe

FEBS Letters ◽  
1997 ◽  
Vol 420 (2-3) ◽  
pp. 161-166 ◽  
Author(s):  
Fumio Motegi ◽  
Kentaro Nakano ◽  
Chikako Kitayama ◽  
Masayuki Yamamoto ◽  
Issei Mabuchi
Keyword(s):  
Schizosaccharomyces Pombe ◽  
Myosin Heavy Chain ◽  
Fission Yeast ◽  
Heavy Chain ◽  
Type Ii ◽  
Type Ii Myosin

scholarly journals A phylogenetic analysis of myosin heavy chain type II sequences corroborates that Acoela and Nemertodermatida are basal bilaterians

2002 ◽  
Vol 99 (17) ◽  
pp. 11246-11251 ◽  
Author(s):  
I. Ruiz-Trillo ◽  
J. Paps ◽  
M. Loukota ◽  
C. Ribera ◽  
U. Jondelius ◽  
...  
Keyword(s):  
Phylogenetic Analysis ◽  
Myosin Heavy Chain ◽  
Heavy Chain ◽  
Type Ii ◽  
Chain Type

Myosin heavy chain isoforms of human muscle after short-term spaceflight

1995 ◽  
Vol 78 (5) ◽  
pp. 1740-1744 ◽  
Author(s):  
M. Y. Zhou ◽  
H. Klitgaard ◽  
B. Saltin ◽  
R. R. Roy ◽  
V. R. Edgerton ◽  
...  
Keyword(s):  
Myosin Heavy Chain ◽  
Heavy Chain ◽  
Space Shuttle ◽  
Vastus Lateralis ◽  
Muscle Fibers ◽  
Rapid Change ◽  
Myosin Heavy Chain Isoforms ◽  
Single Fiber ◽  
Type I ◽  
Type Ii

The influence of microgravity on the myosin phenotype of skeletal muscle fibers in the vastus lateralis of eight crew members was studied before and after 5-day (n = 3) and 11-day (n = 5) spaceflights (space shuttle flights: STS-32, -33 and -34). Single-fiber electrophoresis analyses showed that the proportion of fibers expressing only slow (type I) myosin heavy chain (MHC) in the vastus lateralis was significantly lower after than before 11 days of spaceflight. Although the family of type II MHC isoforms was elevated post- compared with preflight, the distribution among the isoforms of type II MHC was not statistically different. Based on monoclonal and polyclonal antibodies specific for three adult MHC isoforms and single-fiber electrophoresis, approximately 3% of the fibers analyzed coexpressed all three adult MHC isoforms. The results from immunohistochemical staining with two different sets of antibodies indicate a reduction in the percentage of fibers expressing type I MHC as a result of spaceflight. The mean difference, however, was significant only when the fibers were categorized simply as type I or II. These changes appeared to be highly individualized among the astronauts. These results suggest that a rapid change in MHC isoform expression can occur in some muscle fibers after a relatively brief exposure to spaceflight.

Effect of hypothyroidism on myosin heavy chain expression in rat pharyngeal dilator muscles

1992 ◽  
Vol 73 (1) ◽  
pp. 179-187 ◽  
Author(s):  
B. J. Petrof ◽  
A. M. Kelly ◽  
N. A. Rubinstein ◽  
A. I. Pack
Keyword(s):  
Thyroid Hormone ◽  
Myosin Heavy Chain ◽  
Heavy Chain ◽  
Hormone Deficiency ◽  
Type I ◽  
Type Ii ◽  
Airway Patency ◽  
Obstructive Sleep ◽  
Type I Fibers ◽  
Fast Twitch

Although the association between hypothyroidism and obstructive sleep apnea is well established, the effect of thyroid hormone deficiency on contractile proteins in pharyngeal dilator muscles responsible for maintaining upper airway patency is unknown. In the present study, the effects of hypothyroidism on myosin heavy chain (MHC) expression were examined in the sternohyoid, geniohyoid, and genioglossus muscles of adult rats (n = 20). The relative proportions of MHC isoforms present were determined using MHC-specific monoclonal antibodies and oligonucleotide probes. All control muscles showed a paucity of type I MHC fibers, with greater than 90% of fibers containing fast-twitch type II MHCs. In the genioglossus muscle, a population of non-IIa non-IIb fast-twitch type II fibers (putatively identified as type IIx MHC fibers) were detected. Hypothyroidism induced significant changes in MHC expression in all muscles studied. In the sternohyoid, type I fibers increased from 6.2 to 16.9%, whereas type IIa fibers increased from 25.9 to 30.7%. Type I fibers in the geniohyoid increased from 1.2 to 12.8%, whereas type IIa fibers increased from 34.1 to 42.7%. The genioglossus showed the smallest relative increase in type I expression but the greatest induction of type IIa MHC. None of the muscles examined demonstrated reinduction of embryonic or neonatal MHC in response to thyroid hormone deficiency. In summary, hypothyroidism alters the MHC profile of pharyngeal dilators in a muscle-specific manner. These changes may play a role in the pathogenesis of obstructive apnea in hypothyroid patients.

Evidence for three adult fast myosin heavy chain isoforms in type II skeletal muscle fibers in pigs.

1998 ◽  
Vol 76 (6) ◽  
pp. 1584 ◽  
Author(s):  
L Lefaucheur ◽  
R K Hoffman ◽  
D E Gerrard ◽  
C S Okamura ◽  
N Rubinstein ◽  
...  
Keyword(s):  
Skeletal Muscle ◽  
Myosin Heavy Chain ◽  
Heavy Chain ◽  
Muscle Fibers ◽  
Myosin Heavy Chain Isoforms ◽  
Type Ii ◽  
Fast Myosin ◽  
Skeletal Muscle Fibers ◽  
Fast Myosin Heavy Chain

Regulation of myosin heavy chain gene expression after short-term diaphragm inactivation

1998 ◽  
Vol 274 (6) ◽  
pp. L980-L989 ◽  
Author(s):  
Liying Yang ◽  
Johanne Bourdon ◽  
Stewart B. Gottfried ◽  
Walter A. Zin ◽  
Basil J. Petrof
Keyword(s):  
Gene Expression ◽  
Myosin Heavy Chain ◽  
Heavy Chain ◽  
Weight Ratio ◽  
Chain Gene ◽  
Type I ◽  
Type Ii ◽  
Short Term ◽  
Posttranscriptional Control ◽  
Phenotype Transformation

Although prolonged diaphragm denervation (DNV) produces myofiber atrophy and a loss of type I myosin heavy chain (MHC) expression, short-term DNV leads to significant diaphragm hypertrophy. The purpose of this study was to explore the regulation of MHC isoform expression and muscle remodeling during DNV hypertrophy of the diaphragm. Both unilateral and bilateral DNV led to similar changes, with a significant increase in total RNA content and muscle mass but no change in dry-to-wet weight ratio. Sarcomere number was also increased in diaphragm myofibers after DNV (∼20%), suggesting an adaptive response to muscle stretch. There was hypertrophy of type I myofibers and increased coexpression of type I and type II MHCs within single myofibers by immunocytochemistry as well as increased type I MHC (25–46%) and decreased type IIb MHC (14–39%) by SDS-PAGE. Contractility parameters were also consistent with a type II-to-type I MHC phenotype transformation. Importantly, DNV-induced modulation of MHC isoform mRNA transcript levels did not correspond to changes in their cognate proteins, suggesting a major degree of posttranscriptional control. We conclude that DNV hypertrophy of the diaphragm is associated with reciprocal changes in type I and type II MHC isoforms that are directly opposed to the type I-to-type II MHC phenotype transformation reported in the diaphragm DNV atrophy model. Furthermore, in contradistinction to most hypertrophy models, control of MHC gene expression and myofibrillar remodeling after short-term DNV appears to entail major involvement of posttranscriptional regulatory mechanisms.

Myonuclear number and myosin heavy chain expression in rat soleus single muscle fibers after spaceflight

1996 ◽  
Vol 81 (1) ◽  
pp. 145-151 ◽  
Author(s):  
D. L. Allen ◽  
W. Yasui ◽  
T. Tanaka ◽  
Y. Ohira ◽  
S. Nagaoka ◽  
...  
Keyword(s):  
Myosin Heavy Chain ◽  
Soleus Muscle ◽  
Heavy Chain ◽  
Muscle Fibers ◽  
Cross Sectional Area ◽  
Type I ◽  
Type Ii ◽  
Sectional Area ◽  
Cross Sectional ◽  
Fiber Size

The effects of 14 days of spaceflight on myonuclear number, fiber size, and myosin heavy chain (MHC) expression in isolated rat soleus muscle fiber segments were studied. Single soleus muscle fibers from rats flown on the Spacelab Life Sciences-2 14-day mission were compared with those from age-matched ground-based control rats by using confocal microscopy and gel electrophoresis. Spaceflight resulted in a significant reduction in the number of fibers expressing type I MHC and an increase in the number of fibers expressing type IIx or IIa MHC. Space-flight also resulted in an increase in the percentage of fibers coexpressing more than one MHC and in the reexpression of the neonatal isoform of MHC in some fibers. Fiber cross-sectional area was significantly reduced in pure type I MHC-expressing fibers and in fibers coexpressing type I+II MHC but not in fibers expressing one or more type II MHC in the flight rats. The number of myonuclei per millimeter was significantly reduced in type I MHC-expressing fibers from the flight rats but was not significantly different in type I+II and type II MHC-coexpressing fibers. Fibers expressing neonatal MHC were similar in size to control fibers but had significantly fewer myonuclei per millimeter than flight fibers not expressing neonatal MHC. In type I MHC-expressing fibers, the reduction in fiber cross-sectional area was greater than the reduction in myonuclear number; thus the average cytoplasmic volume per myonucleus was significantly lower in flight than in control fibers. The reduction in both myonuclear number and fiber size of fibers expressing type I MHC after 14 days of spaceflight supports the hypothesis that changes in the number of myonuclei may be a contributing factor to the reduction in fiber size associated with chronic unloading of the musculature.

Sign in / Sign up

Export Citation Format

Share Document