Inner and outer arm axonemal dyneins from the Antarctic rockcod Notothenia coriiceps.

Adaptive compensation of enzymatic activities is common among cold-living poikilotherms. Their enzymes often demonstrate higher activities at low temperatures than do homologs from temperate or thermophilic species. To understand the molecular features necessary for cold adaptation of microtubule motor proteins, we have initiated studies of the flagellar dynein ATPases of Antarctic fishes (body temperature range = -1.

Near-field confocal optical spectroscopy (NCOS): subdiffraction optical resolution for biological systems.

Optical resolution is limited by diffraction. However, in near-field microscopes sample illumination is provided through a subwavelength aperture to increase optical resolution. In this study we have evaluated the usefulness of this technique for living biological systems and report two significant improvements in this form of microscopy to enhance optical resolution for biological studies.

Membrane deformation of living glial cells using atomic force microscopy.

Using atomic force microscopy (AFM) it has been possible to detect actin filaments that are beneath the cell membrane of living cells despite the fact that the AFM tip is applied to the surface of the cell. To determine whether the AFM tip actually penetrates or deforms the cell membrane we determined whether an intracellularly trapped fluorescent indicator was lost from cells during AFM. Using epifluorescence illumination to monitor the presence of fluo-3 in the cell, we found that AFM did not cause dye leakage from the cell.