Neurogenesis in Drosophila eye imaginal disc is controlled by interactions of positive and negative regulatory genes. The basic helix-loop-helix (bHLH) transcription factor Atonal (Ato) plays an essential proneural function in the morphogenetic furrow to induce the formation of R8 founder neurons. Bar homeodomain proteins are required for transcriptional repression of ato in the basal undiffere...

Devoid of all known canonical actin-binding proteins, the prevalent parasite Giardia lamblia uses an alternative mechanism for cytokinesis. Unique aspects of this mechanism can potentially be leveraged for therapeutic development. Here, live-cell imaging methods were developed for Giardia to establish division kinetics and the core division machinery. Surprisingly, Giardia cytokinesis occurred ...

We have characterized a human homologue of anillin, a Drosophila actin binding protein. Like Drosophila anillin, the human protein localizes to the nucleus during interphase, the cortex following nuclear envelope breakdown, and the cleavage furrow during cytokinesis. Anillin also localizes to ectopic cleavage furrows generated between two spindles in fused PtK(1) cells. Microinjection of antian...

Cytokinesis, the fi nal step of cell division, requires regionally specialized activities of the microtubule and actin cytoskeletons that are precisely regulated in space and time. We now have a nearly complete “ parts list ” of cytokinesis proteins ( Eggert et al., 2006 ); however, our understanding of the wiring diagram that interconnects cytokinesis proteins is still rudimentary. For example...

T H E CLEAVAGE plane in animal cells and eggs is known to be determined by the position of the mitotic apparatus (cf. Wilson, 1925). A displacement of the mitotic apparatus by centrifugation (Harvey, 1935), mechanical deformation of eggs (Rappaport, 1960, 1961) or by microsurgical operation (Carlson, 1952; Waddington, 1952; Kawamura, 1960; Chambers & Chambers, 1961; Dan & Kuno Kojima, 1963) res...

An appropriate sampling method that provides for the representation of the collected material and the reliability of results plays a crucial role in environmental monitoring. This is especially important in soil quality investigations on sites with a differentiated surface microrelief, as in the case of afforested post-arable soils that have a specific, deep furrow-and-ridge microrelief. The pr...

Animal cells are cleaved by the formation and contraction of an extremely thin actomyosin band. In most cases this contractile band seems to form synchronously around the whole equator of the cleaving cell; however in giant cells it first forms near the mitotic apparatus and then slowly grows outwards over the cell. We studied the relationship of calcium to such contractile band growth using ae...

Emergence of the cytokinetic Rho zone that orchestrates formation and ingression of the cleavage furrow had been explained previously via microtubule-dependent cortical concentration of Ect2, a guanine nucleotide exchange factor for Rho. The results of a recent publication now demonstrate that, en route from resting cortex to fully established furrow, there lies a regime of cortical excitabilit...