Google Play icon

A molecular ruler in eukaryotic cells

Share
Posted November 20, 2014
This news or article is intended for readers with certain scientific or professional knowledge in the field.

Researchers led by Professor Masahide Kikkawa at the Graduate School of Medicine, the University of Tokyo have discovered that a protein complex, CCDC39/CCDC40, works as a nanometer-sized molecular ruler in the cell.

Upper left: Cilia are present in the human trachea in order to discharge foreign bodies as sputum. Top right: fine three-dimensional structure of cilia taken by cryo-electron tomography. The 96-nanometer periodic structure is visible. Bottom: If there is no nano-molecular ruler, a repeating structure is not formed and cilia are immotile. When the molecular ruler is present, dynein motor proteins are aligned in accordance with the ruler’s 96-nanometer period and the cilia are motile. © 2014 Masahide Kikkawa.

Upper left: Cilia are present in the human trachea in order to discharge foreign bodies as sputum.
Top right: fine three-dimensional structure of cilia taken by cryo-electron tomography. The 96-nanometer periodic structure is visible.
Bottom: If there is no nano-molecular ruler, a repeating structure is not formed and cilia are immotile. When the molecular ruler is present, dynein motor proteins are aligned in accordance with the ruler’s 96-nanometer period and the cilia are motile. © 2014 Masahide Kikkawa.

The nano-molecular ruler was discovered in incredibly thin motile cellular organelles called “cilia”. Cilia are found in many tissues such as the trachea, sperm, oviduct, and brain. Cilia generate fluid flows by beating motions, which are driven by a motor protein called dynein. Dyneins are regularly arranged inside cilia with a 96-nm periodicity.

In this study, Assistant Professors Toshiyuki Oda and Haruaki Yanagisawa in Professor Kikkawa’s lab used cryo-electron tomography, which can visualize cell ultrastructures without staining, and discovered that the FAP59/FAP172 complex works as a 96-nm long “nano-molecular ruler”. The complex arranges dyneins with 96-nm repeat and enables coordinated motion of the motor complex.

Since mutations in this nano-molecular ruler are found among congenital so-called “ciliary diseases,” this research will contribute to research into infertility, respiratory disease, hydrocephalus and other cilia-related diseases. The discovery is also expected to be of relevance to the design of complex nanomachines.

Source: University of Tokyo

Featured news from related categories:

Technology Org App
Google Play icon
85,409 science & technology articles

Most Popular Articles

  1. New treatment may reverse celiac disease (October 22, 2019)
  2. "Helical Engine" Proposed by NASA Engineer could Reach 99% the Speed of Light. But could it, really? (October 17, 2019)
  3. New Class of Painkillers Offers all the Benefits of Opioids, Minus the Side Effects and Addictiveness (October 16, 2019)
  4. The World's Energy Storage Powerhouse (November 1, 2019)
  5. Plastic waste may be headed for the microwave (October 18, 2019)

Follow us

Facebook   Twitter   Pinterest   Tumblr   RSS   Newsletter via Email