Richard Linck uncovers structure, protein elements critical to human function and disease.
This paper, from the laboratories of Dr. Richard Linck, University of Minnesota, and his collaborator, Dr. Daniela Nicastro, Brandeis University, has been recognized by the Journal of Biological Chemistry's Cell Biology as Best Paper of the Year for 2014. Just 21 papers of the thousands published by the journal through the year received the honor.
Cilia are microscopic, hair-like structures occurring in large numbers on the surface of some of the body’s cells and are involved in movement and perception. Cilia are composed of double microtubules, which are in turn composed of protofilaments.
Utilizing cryo-electron tomography and sea urchin sperm tails, researchers identified a single ribbon of four protofilaments in each microtubule, with each microtubule containing a single filament of the protein tektin. Despite the extremely high resolution and protofilament ribbon identifications, there is still a small zone of confusion where the filament meets the ribbon. Thus, it is remains unclear how the filament fits into the structure of the ribbon.
As part of the push for structural mapping, Linck and his research team applied biochemical analysis to the ribbon. In this assessment, several proteins have been localized to the ribbon, including tektin and two others casually associated with human disease, including juvenile myoclonic epilepsy.
It is still unclear if the cilia are directly involved in the cause of the epilepsy and other diseases, or if the relevant proteins function in other, non-ciliary ways to cause disease. However, the mapping itself begins to unlock those clues. Future research is needed to understand the relationship of these ribbon-associated proteins to human disease, as well as to better understand how the filament is structured in the larger ribbon.