A new type of Chlamydomonas mutant, which lacks the outer dynein arm but can swim, was isolated. Sodium dodecyl sulphate/polyacrylamide gel electrophoresis showed that four of the ten high-molecular-weight bands of dynein present in the wild-type axoneme are missing or diminished in the mutant axoneme. The mutant has a swimming rate of about 35 micrometers/s and a flagellar beat frequency of ab...

Ciliary beat frequency (CBF) measurements provide valuable information for diagnosing of primary ciliary dyskinesia (PCD). We developed a system for measuring CBF, used it in association with electron microscopy to diagnose PCD, and then analyzed characteristics of PCD patients. The CBF measurement system was based on power spectra measured through digital imaging. Twenty-four patients suspecte...

Despite recent advances in the fields of cytochemistry and electron microscopy the processes which are responsible for flagellar movement, and their chemical foundations, cannot be described with any certainty. In a previous communication (Holwill & Silvester, 1965) we described the variation with temperature of the frequency of the flagellar beat in Strigomonas oncopelti and deduced thermodyna...

We have examined thin sections and replicas of freeze-fractured cilia of Tetrahymena pyriformis. The ciliary necklace located at the base of all freeze-fractured oral and somatic cilia has been studied in thin sections. Since electron-dense linkers have been found to connect both microtubule doublets and triplets to the ciliary membrane at the level of the necklace, the linkers and the associat...

Abstract The beating of cilia and flagella is essential to perform many important biological functions, including generating fluid flows on the cell surface or propulsion micro-organisms. In this work, we analyze motion isolated demembranated from green algae Chlamydomonas reinhardtii , which act as ATP-driven micro-swimmers. exhibit an asymmetric waveform that known involve superposition a sta...

Retrograde intraflagellar transport (IFT) is required for assembly of cilia. We identify a Chlamydomonas flagellar protein (flagellar-associated protein 163 [FAP163]) as being closely related to the D1bIC(FAP133) intermediate chain (IC) of the dynein that powers this movement. Biochemical analysis revealed that FAP163 is present in the flagellar matrix and is actively trafficked by IFT. Further...

We have investigated the role of motile cilia in mechanotransduction by statocysts of the nudibranch mollusk Hermissenda crassicornis. Movement of the cilia that experience the weight of statoconia causes increased variance of voltage noise and membrane depolarization of the statocyst hair cell. Two complementary approaches were used to immobilize the cilia. Vanadate anion was iontophoretically...

We have examined thin sections and replicas of freeze-fractured cilia of Tetrahymena pyriformis . The ciliary necklace located at the base of all freeze-fractured oral and somatic cilia has been studied in thin sections . Since electron-dense linkers have been found to connect both microtubule doublets and triplets to the ciliary membrane at the level of the necklace, the linkers and the associ...