Biomaterial Database

Three-headed outer arm dynein from Chlamydomonas that can functionally combine with outer-arm-missing axonemes. 1992

S Takada, and H Sakakibara, and R Kamiya

Department of Molecular Biology, School of Science, Nagoya University, Aichi.

A procedure was developed for isolating Chlamydomonas outer-arm dynein that can functionally combine with the axoneme of an outer-arm-missing mutant, oda1. Previous studies showed that the outer-arm dynein of this organism, containing three heavy chains (alpha, beta, gamma), dissociates upon extraction with a high-salt-concentration buffer solution into an 18-S particle containing the alpha and beta heavy chains and a 12-S particle containing the gamma heavy chain. It was found, however, that the three heavy chains did not dissociate if the high-salt extract was centrifuged in the presence of Mg2+; the three chains constituted a single species (23-S dynein) sedimenting at about 23 S and displayed a three-headed bouquet configuration in electron micrographs. Furthermore, the 23-S dynein had the activity to bind to the axonemes of oda1 and increase the reactivated motility of detergent-extracted cell models; its addition increased the beat frequency from 28 Hz to 53 Hz, a frequency comparable to that of wild-type axoneme. The 18-S and 12-S dyneins, on the other hand, were unable to increase the motility of oda1 axonemes even when added together. The new protocol thus enables purification of outer-arm dynein that retains its functional activity. It will provide a useful experimental system with which to study the mechanism of outer-arm function.

UI	MeSH Term	Description	Entries
D008854	Microscopy, Electron	Microscopy using an electron beam, instead of light, to visualize the sample, thereby allowing much greater magnification. The interactions of ELECTRONS with specimens are used to provide information about the fine structure of that specimen. In TRANSMISSION ELECTRON MICROSCOPY the reactions of the electrons that are transmitted through the specimen are imaged. In SCANNING ELECTRON MICROSCOPY an electron beam falls at a non-normal angle on the specimen and the image is derived from the reactions occurring above the plane of the specimen.	Electron Microscopy
D002499	Centrifugation, Density Gradient	Separation of particles according to density by employing a gradient of varying densities. At equilibrium each particle settles in the gradient at a point equal to its density. (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)	Centrifugations, Density Gradient,Density Gradient Centrifugation,Density Gradient Centrifugations,Gradient Centrifugation, Density,Gradient Centrifugations, Density
D004398	Dyneins	A family of multi-subunit cytoskeletal motor proteins that use the energy of ATP hydrolysis, generated by a ring of AAA ATPASES in the dynein heavy chain, to power a variety of cellular functions. Dyneins fall into two major classes based upon structural and functional criteria.	ATPase, Dynein,Adenosinetriphosphatase, Dynein,Dynein,Dynein ATPase,Dynein Adenosinetriphosphatase,Dynein Heavy Chain,Dynein Intermediate Chain,Dynein Light Chain,Dynein Light Intermediate Chain,Adenosine Triphosphatase, Dynein,Dynein Heavy Chains,Dynein Intermediate Chains,Dynein Light Chains,Dynein Light Intermediate Chains,Chain, Dynein Heavy,Chain, Dynein Intermediate,Chain, Dynein Light,Chains, Dynein Heavy,Chains, Dynein Intermediate,Chains, Dynein Light,Dynein Adenosine Triphosphatase,Heavy Chain, Dynein,Heavy Chains, Dynein,Intermediate Chain, Dynein,Intermediate Chains, Dynein,Light Chain, Dynein,Light Chains, Dynein
D005407	Flagella	A whiplike motility appendage present on the surface cells. Prokaryote flagella are composed of a protein called FLAGELLIN. Bacteria can have a single flagellum, a tuft at one pole, or multiple flagella covering the entire surface. In eukaryotes, flagella are threadlike protoplasmic extensions used to propel flagellates and sperm. Flagella have the same basic structure as CILIA but are longer in proportion to the cell bearing them and present in much smaller numbers. (From King & Stansfield, A Dictionary of Genetics, 4th ed)	Flagellum
D000818	Animals	Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA.	Animal,Metazoa,Animalia
D016825	Chlamydomonas reinhardtii	A species of GREEN ALGAE. Delicate, hairlike appendages arise from the flagellar surface in these organisms.	Chlamydomonas reinhardii,Chlamydomonas reinhardius,Chlamydomonas reinhardtius,reinhardius, Chlamydomonas,reinhardtii, Chlamydomonas