THE CRYO-EM 3D IMAGE RECONSTRUCTION OF ISOLATED LETHOCERUS INDICUS Z-DISCS

Details

• Alternative Title:
  J Muscle Res Cell Motil
• Personal Author:
  Yeganeh, Fatemeh Abbasi ; Summerill, Corinne ; Hu, Zhongjun ; Rahmani, Hamidreza ; Taylor, Dianne W. ; Taylor, Kenneth A.
• Description:
  The Z-disk of striated muscle defines the ends of the sarcomere, which repeats many times within the muscle fiber. Here we report application of cryoelectron tomography and subtomogram averaging to Z-disks isolated from the flight muscles of the large waterbug Lethocerus indicus. We use high salt solutions to remove the myosin containing filaments and use gelsolin to remove the actin filaments of the A- and I-bands leaving only the thin filaments within the Z-disk which were then frozen for cryoelectron microscopy. The Lethocerus Z-disk structure is similar in many ways to the previously studied Z-disk of the honeybee Apis mellifera. At the corners of the unit cell are positioned trimers of paired antiparallel F-actins defining a large solvent channel, whereas at the trigonal positions are positioned F-actin trimers converging slowly towards their (+) ends defining a small solvent channel through the Z-disk. These near parallel F-actins terminate at different Z-heights within the Z-disk. The two types of solvent channel in Lethocerus are similar in size compared to those of Apis which are very different in size. Two types of α-actinin crosslinks were observed between oppositely oriented actin filaments. In one of these, the α-actinin long axis is almost parallel to the F-actins it crosslinks. In the other, the α-actinins are at a small but distinctive angle with respect to the crosslinked actin filaments. The utility of isolated Z-disks for structure determination is discussed.
• Subjects:
  Actinin Actins Animals Cryoelectron Microscopy Image Processing, Computer-Assisted Muscle, Skeletal Muscle Proteins Sarcomeres Solvents
• Keywords:
  Electron Tomography F-actin Kettin Projectin α-actinin
• Source:
  J Muscle Res Cell Motil. 44(4):271-286
• Pubmed ID:
  37661214
• Pubmed Central ID:
  PMC10843718
• Document Type:
  Journal Article
• Funding:
  S10 RR025080/RR/NCRR NIH HHSUnited States/ ; S10 OD018142/OD/NIH HHSUnited States/ ; R01 GM30598/GM/NIGMS NIH HHSUnited States/ ; R35 GM139616/GM/NIGMS NIH HHSUnited States/ ; S10 OD018142/CD/ODCDC CDC HHSUnited States/ ; R01 GM030598/GM/NIGMS NIH HHSUnited States/ ; R01 GM30598/GM/NIGMS NIH HHSUnited States/ ; S10 RR025080/RR/NCRR NIH HHSUnited States/ ; S10 OD018142/CD/ODCDC CDC HHSUnited States/
• Volume:
  44
• Issue:
  4
• Collection(s):
  CDC Public Access
• Main Document Checksum:
  urn:sha-512:c7058d86366a570df542ee10355a9659cad172ec6b1e378b30a61ad1461e864cbff76b313d7563bbd00b771e895c994406dcfb24dfa958f489963f99ba9ddedb
• Download URL:
  https://stacks.cdc.gov/view/cdc/147733/cdc_147733_DS1.pdf
• File Type:
  [PDF - 2.76 MB ]