Nudel Contributes to Microtubule Anchoring at the Mother Centriole and Is Involved in Both Dynein-dependent and -independent Centrosomal Protein Assembly

Abstract

The centrosome is the major microtubule-organizing center in animal cells. Although the cytoplasmic dynein regulator Nudel interacts with centrosomes, its role herein remains unclear. Here, we show that in Cos7 cells Nudel is a mother centriole protein with rapid turnover independent of dynein activity. During centriole duplication, Nudel targets to the new mother centriole later than ninein but earlier than dynactin. Its centrosome localization requires a C-terminal region that is essential for associations with dynein, dynactin, pericentriolar material (PCM)-1, pericentrin, and gamma-tubulin. Overexpression of a mutant Nudel lacking this region, a treatment previously shown to inactivate dynein, dislocates centrosomal Lis1, dynactin, and PCM-1, with little influence on pericentrin and gamma-tubulin in Cos7 and HeLa cells. Silencing Nudel in HeLa cells markedly decreases centrosomal targeting of all the aforementioned proteins. Silencing Nudel also represses centrosomal MT nucleation and anchoring. Furthermore, Nudel can interact with pericentrin independently of dynein. Our current results suggest that Nudel plays a role in both dynein-mediated centripetal transport of dynactin, Lis1, and PCM-1 as well as in dynein-independent centrosomal targeting of pericentrin and gamma-tubulin. Moreover, Nudel seems to tether dynactin and dynein to the mother centriole for MT anchoring.

Downregulation of Protein 4.1R, a Mature Centriole Protein, Disrupts Centrosomes, Alters Cell Cycle Progression, and Perturbs Mitotic Spindles and Anaphase

“…However, 4.1R epitopes are largely noncoincident with C-Nap1 at the proximal ends of centrioles. We also found that 4.1R epitopes were consistently targeted in tandem with ninein and ODF2 to newly maturing centrioles during centriole duplication, unlike some other proteins, such as Nudel, that arrive after ninein (18). 4.1R localization at centrosomes is not dependent on microtubules (29), and our data reported here suggest that 4.1R may be an integral component of centrioles bearing distal/subdistal appendages.…”

Guiding Neuronal Cell Migrations

“…This family also includes Ndel1 and dynein (Morris et al 1998). Ndel1 is required for targeting Lis1 and dynein to the centrosome, and facilitates the nucleation and anchoring of microtubules to the centrosome (Guo et al 2006). In addition, Ndel1 facilitates the interaction between Lis1 and dynein and regulates dynein-mediated retrograde transport (Gupta et al 2003;Li et al 2005;Mesngon et al 2006;Smith et al 2000).…”

Let's huddle to prevent a muddle: centrosome declustering as an attractive anticancer strategy

“…Dynein at the kinetochore may be involved in kinetochore-microtubule attachment and SAC silencing. 103 The dynein/dynactin complex not only transports a variety of proteins (including several others that promote microtubule nucleation) to the centrosome [104][105][106][107][108] but also nucleates microtubules itself. 109 Dynein/dynactin is also necessary for centrosomal retention and focusing of microtubules, regulation of mitotic spindle positioning and length, and migration of interphase cells.…”