TY - GEN
T1 - The protein-driven ciliary motility in embryonic nodes
T2 - ASME 2013 International Mechanical Engineering Congress and Exposition, IMECE 2013
AU - Chen, Duanduan
AU - Ren, Jun
AU - Shinohara, Kyosuke
AU - Hamada, Hiroshi
PY - 2013
Y1 - 2013
N2 - The movement of embryonic cilia presents a crucial function in specifying left-right axis for vertebrates. Those mono-cilia are primary (9+0) cilia, whose characteristic architecture is based on a cylindrical arrangement of 9 microtubule doublets. Dynein motors located between adjacent doublets convert the chemical energy of ATP hydrolysis into mechanical work that induces doublet sliding. Passive components, such as the mediated cytoplasm, the ciliary membrane, and other possibly-existent structures constraint the ciliary motion and maintain the cilia structural integrity, thus resulting in the axonemal bending. Dynein motors located along microtubule doublets in a motile nodal cilium activate in a sequential manner. However, due to inherent difficulties, the dynein activation patterns in moving cilia can hardly be directly observed. The exact mechanism that controls ciliary motion is still unrevealed. In this work, we present a protein-structure model reconstructed from transmission electron microscopy image set of a wide-type embryonic cilium to study the dynein-dependent ciliary motility. This model includes time accurate threedimensional solid mechanics analysis of the sliding between adjacent microtubule doublets and their induced ciliary bending. As a conceptual test, the mathematical model provides a platform to investigate various assumptions of dynein activity, which facilitates us to evaluate their rationality and to propose the most possible dynein activation pattern. The proposed protein-trigger pattern can reproduce the rotation-like ciliary motion as observed by experiments. Further application of this approach to mutant cilia with ultrastructural modifications also shows consistency to experimental observations. This computational model based on solid mechanics analysis may improve our understandings regarding the protein-beating problems of cilia, and may guide and inspire further experimental investigations on this topic.
AB - The movement of embryonic cilia presents a crucial function in specifying left-right axis for vertebrates. Those mono-cilia are primary (9+0) cilia, whose characteristic architecture is based on a cylindrical arrangement of 9 microtubule doublets. Dynein motors located between adjacent doublets convert the chemical energy of ATP hydrolysis into mechanical work that induces doublet sliding. Passive components, such as the mediated cytoplasm, the ciliary membrane, and other possibly-existent structures constraint the ciliary motion and maintain the cilia structural integrity, thus resulting in the axonemal bending. Dynein motors located along microtubule doublets in a motile nodal cilium activate in a sequential manner. However, due to inherent difficulties, the dynein activation patterns in moving cilia can hardly be directly observed. The exact mechanism that controls ciliary motion is still unrevealed. In this work, we present a protein-structure model reconstructed from transmission electron microscopy image set of a wide-type embryonic cilium to study the dynein-dependent ciliary motility. This model includes time accurate threedimensional solid mechanics analysis of the sliding between adjacent microtubule doublets and their induced ciliary bending. As a conceptual test, the mathematical model provides a platform to investigate various assumptions of dynein activity, which facilitates us to evaluate their rationality and to propose the most possible dynein activation pattern. The proposed protein-trigger pattern can reproduce the rotation-like ciliary motion as observed by experiments. Further application of this approach to mutant cilia with ultrastructural modifications also shows consistency to experimental observations. This computational model based on solid mechanics analysis may improve our understandings regarding the protein-beating problems of cilia, and may guide and inspire further experimental investigations on this topic.
UR - http://www.scopus.com/inward/record.url?scp=84903454932&partnerID=8YFLogxK
U2 - 10.1115/IMECE2013-62460
DO - 10.1115/IMECE2013-62460
M3 - Conference contribution
AN - SCOPUS:84903454932
SN - 9780791856222
T3 - ASME International Mechanical Engineering Congress and Exposition, Proceedings (IMECE)
BT - Biomedical and Biotechnology Engineering
PB - American Society of Mechanical Engineers (ASME)
Y2 - 15 November 2013 through 21 November 2013
ER -