In a multitude of life’s processes, cilia and flagella are found indispensable. Recently, the biflagellated chlorophyte alga Chlamydomonas has become a model organism for the study of ciliary motility and synchronization. Here, we use high-speed, high-resolution imaging of single pipette-held cells to quantify the rich dynamics exhibited by their flagella. Underlying this variability in behavio...

Wild-type Chlamydomonas reinhardtii carry two flagella per cell that are used for both motility and mating. We describe a mutant, vfl-1, in which the biflagellate state is disrupted such that the number of flagella per cell ranges from 0 to as many as 10. vfl-1 cells possess the novel ability to assemble new flagella throughout the G1 portion of the cell cycle, resulting in an average increase ...

Regulation of motile 9+2 cilia and flagella depends on interactions between radial spokes and a central pair apparatus. Although the central pair rotates during bend propagation in flagella of many organisms and rotation correlates with a twisted central pair structure, propulsive forces for central pair rotation and twist are unknown. Here we compared central pair conformation in straight, qui...

Eukaryotic flagella and cilia have attracted the attention of many researchers over the last century, since they are highly arranged organelles and show sophisticated bending movements. Two important cytoskeletal and motor proteins, tubulin and dynein, were first found and described in flagella and cilia. Half a century has passed since the discovery of these two proteins, and much information ...

Salmonella enterica serovar Typhimurium produces two types of filamentous appendages on its surface. Fimbriae mediate adherence to tissues and cells via receptor-specific interactions, and flagella are the organelles of motility. These appendages play a role in colonization and dissemination, respectively, from infected surfaces and may be important components of bacterial survival. Increased e...

A wet-mount technique for staining bacterial flagella is highly successful when a stable stain and regular slides and cover slips are used. Although not producing a permanent mount, the technique is simple for routine use when the number and arrangement of flagella are critical in identifying species of motile bacteria.

Intraflagellar transport is involved in the assembly of cilia and eukaryotic flagella. Two recent studies have shown that defects in intraflagellar transport prevent assembly of sensory cilia in Drosophila, leaving the fly deaf and uncoordinated. Surprisingly, the mutant sperm flagella have normal structure and motility.

C ompetition for the cytoplasmic tail of an integrin allows cells to read different matrix densities, say Millon-Frémillon et al. The tail region of β1 integrin is tiny—only 47 amino acids long. That doesn’t leave much room for the binding of cytoplasmic accessory proteins that help control the integrin’s activation state. When talin holds this position, it fl ips open integrin as a fi rst step...