Evidence for a Direct Role of Nascent Basal Bodies During Spindle Pole Initiation in the Green Alga Spermatozopsis similis

Structural inheritance in Paramecium: ultrastructural evidence for basal body and associated rootlets polarity transmission through binary fission⋆

“…This result suggests that the rootlets are necessary for the process. Ultrastructural observations support the hypothesis that indeed the striated rootlet could play a peculiar role, as already suggested in Spermatozopsis ( Lechtreck and Gronow, 1999): the pro-basal body appears very close to this rootlet, which could thus create a favourable environment for this assembly. This hypothesis is reinforced by the detection of gamma tubulin, known to be necessary for basal body duplication in Paramecium (Ruiz et al, 1999).…”

“…The observations show that basal body assembly occurs after modification of the parental pattern, suggesting that, to be competent for templating basal body assembly, parental basal bodies must have a complete set of rootlets. Pro-basal bodies appear close to the parental striated rootlet, which could behave as an attracting centre as already suggested in another species (Lechtreck and Gronow, 1999). The nucleation of new associated rootlets is detected after the assembly of the basal body microtubular triplets: basal body assembly thus occurs before that of its appendages.…”

“…The two structures, centrioles and basal bodies, are involved in both similar and different functions at the cellular level. Both of them are found at the microtubule organising centres of the cell (Tassin and Bornens, 1999;Lechtreck and Gronow, 1999;Uyeda and Furuya, 1985); but centrioles are components of the main intracytoplasmic microtubule organising centre (MTOC), the centrosome, while basal bodies are by definition peripherally located. If the main function of basal bodies appears clearly as templates for ciliary axoneme assembly, that of centrioles as components of the centrosome remains less clear although some hypotheses are now emerging (Piel et al, 2000(Piel et al, , 2001.…”

Three-dimensional analysis of mitosis and cytokinesis in the binucleate parasiteGiardia intestinalis

“…These basal bodies of Chlamydomonas organize the spindle microtubules in a bipolar array and also appear to play a role in spindle positioning (Coss, 1974;Ehler et al, 1995). The association of flagellar basal bodies with the spindle poles may serve to ensure equal partitioning of basal bodies in each division cycle, thereby preserving the number of flagella in each daughter cell (Dutcher, 2003;Marshall and Rosenbaum, 2000;Heath, 1980;Lechtreck and Grunow, 1999;Wright et al, 1989).…”

ChlamydomonasDIP13 and human NA14: a new class of proteins associated with microtubule structures is involved in cell division

“…Flagella/cilia consist of about 250 different polypeptides (Dutcher, 1995a), and roughly 200 of these have already been identified both by conventional methods and by a recent proteomic analysis of human cilia (Dutcher, 1995a;Ostrowski et al, 2002). By contrast, basal bodies/centrioles play an important role in mitosis and subsequent cell cleavage (Johnson and Porter, 1968;Ehler et al, 1995;Paoletti and Bornens, 1997;Lechtreck and Grunow, 1999;Marshall and Rosenbaum, 2000) and contain about 200 different polypeptides (Dutcher, 1995b). However, few basal body proteins have been described to date, including centrin in the basal body distal lumen, the microtubule-nucleating protein γ-tubulin in the basal body proximal lumen (Fuller et al, 1995;Marshall and Rosenbaum, 2000) and δ-tubulin (Dutcher and Trabuco, 1998), which is necessary for triplet MT formation.…”