scholarly journals Actin Filaments in Flight Muscle Z-disks of Lethocerus indicus Show Screw Symmetry, Not Rotational Symmetry

2020 ◽  
Vol 26 (S2) ◽  
pp. 1298-1301
Author(s):  
Fatemeh Abbasi Yeganeh ◽  
Corrine Summerill ◽  
Dianne Taylor ◽  
Hamidreza Rahmani ◽  
Kenneth Taylor
Keyword(s):  
Actin Filaments ◽  
Flight Muscle ◽  
Rotational Symmetry ◽  
Lethocerus Indicus

scholarly journals Actin Filaments in Flight Muscle Z-disks of Lethocerus indicus Show Screw Symmetry, not Rotational Symmetry

2020 ◽  
Vol 118 (3) ◽  
pp. 294a
Author(s):  
Fatemeh A. Abbasi Yeganeh ◽  
Corinne Summerill ◽  
Zhongjun Hu ◽  
Hamidreza Rahmani ◽  
Dianne Taylor ◽  
...  
Keyword(s):  
Actin Filaments ◽  
Flight Muscle ◽  
Rotational Symmetry ◽  
Lethocerus Indicus

scholarly journals Three-dimensional reconstruction of the Z disk of sectioned bee flight muscle.

1989 ◽  
Vol 108 (5) ◽  
pp. 1761-1774 ◽  
Author(s):  
N Q Cheng ◽  
J F Deatherage
Keyword(s):  
Central Region ◽  
Actin Filaments ◽  
Flight Muscle ◽  
Three Dimensional ◽  
Opposite Polarity ◽  
Dimensional Structure ◽  
Three Dimensional Reconstruction ◽  
Thin Sections ◽  
Dimensional Reconstruction ◽  
Cross Links

The three-dimensional structure of the central region of the Z disk of honeybee flight muscle has been determined to a resolution of 70 A by three-dimensional reconstruction from electron micrographs of tilted thin sections. The reconstructions show a complex assembly in which actin filaments terminate and are cross-linked together; a number of structural domains of this network are resolved in quantitative three-dimensional detail. The central region of the Z disk contains two sets of overlapping actin filaments of opposite polarity, which originate in the sarcomeres adjacent to the Z disk, and connections between these filaments. The filaments are deflected by the attachment of cross-links; spacing between filaments change by greater than 100 A during their passage through the Z disk. Each actin filament is linked by connecting structures to four filaments of opposite polarity and two filaments are of the same polarity. Four types of connecting density domain are observed in association with pairs of filaments of opposite polarity: C1, C2, C3, and C5. Two of these, C3 and C5, are associated with the ends of actin filaments. Another connection, C4, is associated with three filaments of the same polarity; C4 is threefold symmetric.

Fundamental step size in single cardiac and skeletal sarcomeres

2002 ◽  
Vol 283 (3) ◽  
pp. C735-C742 ◽  
Author(s):  
Olga Yakovenko ◽  
Felix Blyakhman ◽  
Gerald H. Pollack
Keyword(s):  
Actin Filaments ◽  
Thin Filament ◽  
Time Course ◽  
Flight Muscle ◽  
Length Change ◽  
Step Size ◽  
Fundamental Step ◽  
Dynamic Events ◽  
Photodiode Array ◽  
Parallel Measurements

In attempting to deduce the size of the elementary molecular translation step, recent experiments using single myosin molecules translating over actin filaments have shown a consistent step size of 5.4 nm (10, 21). We have carried out parallel measurements on single myofibrils from rabbit cardiac muscle and bumblebee flight muscle. Activated specimens were released or stretched with a motor-imposed ramp, and the time course of length of individual sarcomeres was measured by projecting the image of the striations onto a linear photodiode array and tracking the spacing between A-band centroids. We confirmed the 5.4-nm step. With subnanometer precision, however, we find that this value is two times that of a more fundamental step size of 2.7 nm. Step sizes were always integer multiples of 2.7 nm, whether the length change was positive or negative. This value is equal to the linear repeat of actin monomers along the thin filament, a result that ties dynamic events to molecular structure and places narrow constraints on any proposed molecular mechanism.

scholarly journals CryoEM structure of Drosophila flight muscle thick filaments at 7 Å resolution

2020 ◽  
Vol 3 (8) ◽  
pp. e202000823
Author(s):  
Nadia Daneshparvar ◽  
Dianne W Taylor ◽  
Thomas S O’Leary ◽  
Hamidreza Rahmani ◽  
Fatemeh Abbasiyeganeh ◽  
...  
Keyword(s):  
Striated Muscle ◽  
Flight Muscle ◽  
Myosin Ii ◽  
Coiled Coil ◽  
Fruit Fly ◽  
Actin Binding ◽  
Thick Filaments ◽  
Flight Muscles ◽  
Lethocerus Indicus ◽  
Globular Head

Striated muscle thick filaments are composed of myosin II and several non-myosin proteins. Myosin II’s long α-helical coiled-coil tail forms the dense protein backbone of filaments, whereas its N-terminal globular head containing the catalytic and actin-binding activities extends outward from the backbone. Here, we report the structure of thick filaments of the flight muscle of the fruit fly Drosophila melanogaster at 7 Å resolution. Its myosin tails are arranged in curved molecular crystalline layers identical to flight muscles of the giant water bug Lethocerus indicus. Four non-myosin densities are observed, three of which correspond to ones found in Lethocerus; one new density, possibly stretchin-mlck, is found on the backbone outer surface. Surprisingly, the myosin heads are disordered rather than ordered along the filament backbone. Our results show striking myosin tail similarity within flight muscle filaments of two insect orders separated by several hundred million years of evolution.

Structure of The Z Disk of Sectioned Bee Flight Muscle

1990 ◽  
Vol 48 (1) ◽  
pp. 512-513
Author(s):  
J.F. Deatherage ◽  
N. Cheng
Keyword(s):  
Complex Network ◽  
Actin Filament ◽  
Electron Micrographs ◽  
Central Region ◽  
Actin Filaments ◽  
Flight Muscle ◽  
Opposite Polarity ◽  
Structural Domains ◽  
Thin Sections ◽  
Averaging Technique

Information from oblique thin sections and from 3-D reconstructions of tilted transverse thin sections has been combined to determine the 3-D structure of the honeybee flight muscle Z disk at 7øÅ resolution. The overall symmetry and structure of the Z disk and its relationship to the rest of the myofibril have been determined by tracing filaments and connecting elements on electron images of oblique sections which have been enhanced by a local crystallographic averaging technique .The 3-D structure of the central region of the Z disk of honeybee flight muscle has been determined by crystallographic 3-D reconstruction from electron micrographs of tilted thin sections. The reconstructions show a complex network in which actin filaments terminate and are crosslinked together (Figure 1); a number of structural domains are resolved in the network.The central region of the Z disk contains two sets of overlapping actin filaments of opposite polarity, which originate in the sarcomeres adjacent to the Z disk, and connections between these filaments. The filaments are deflected by the attachment of crosslinks; spacings between filaments change by over 1øøÅ during their passage through the Z disk. Each actin filament is linked by connecting structures to four filaments of opposite polarity and two filaments of the same polarity.

scholarly journals Arrangement of filaments and cross-links in the bee flight muscle Z disk by image analysis of oblique sections.

1989 ◽  
Vol 108 (5) ◽  
pp. 1775-1782 ◽  
Author(s):  
J F Deatherage ◽  
N Q Cheng ◽  
B Bullard
Keyword(s):  
Actin Filaments ◽  
Flight Muscle ◽  
Three Dimensional ◽  
Thick Filament ◽  
Opposite Polarity ◽  
Dimensional Structure ◽  
Central Plane ◽  
Thin Sections ◽  
Three Dimensional Structure ◽  
Rotation Axes

Information from oblique thin sections and from three-dimensional reconstructions of tilted, transverse thin sections (Cheng, N., and J. F. Deatherage. 1989. J. Cell Biol. 108:1761-1774) has been combined to determine the three-dimensional structure of the honeybee flight muscle Z disk at 70-A resolution. The overall symmetry and structure of the Z disk and its relationship to the rest of the myofibril have been determined by tracing filaments and connecting elements on electron images of oblique sections which have been enhanced by a local crystallographic averaging technique. In the three-dimensional structure, the connecting density between actin filaments can be described as five compact, crystallographically nonequivalent domains. Features C1 and C2 are located on the transverse twofold rotation axes in the central plane of the Z disk. They are associated with the sides of actin filaments of opposite polarity. Features C3, C4, and C5 are present in two symmetry-related sets which are located on opposite sides of the central plane. C3 and C5 are each associated with two filaments of opposite polarity, interacting with the side of one filament and the end of the other filament. C3 and C5 may be involved in stabilizing actin filament ends inside the Z disk. The location of the threefold symmetric connection C4, relative to the thick filament of the adjacent sarcomere, is determined and its possible relationship to the C filament is considered.

scholarly journals 3-D Structure of Z-disks Isolated from the Flight Muscle of Lethocerus indicus

2019 ◽  
Vol 25 (S2) ◽  
pp. 1296-1297
Author(s):  
Fatemeh Abbasi Yeganeh ◽  
Corinne Summerill ◽  
Dianne W. Taylor ◽  
Hamidreza Rahmani ◽  
Kenneth A. Taylor
Keyword(s):  
Flight Muscle ◽  
Lethocerus Indicus
Sign in / Sign up

Export Citation Format

Share Document