Human Cep 192 Is Required and Spindle Assembly

Cep192 Depletion Does Not Impact Centriole Duplication but Induces Premature Centriole Disengagement Depletion of Cep192 does not appear to impact the assembly or replication of centrioles (Figure 3B and Figure S3A). The majority of Cep192 siRNA-treated cells showed four dots of centrin, corresponding to the two parental centrioles and their daughter pairs, in mitosis. However, in most of these cells, centrioles didnot localize to MTOCs. Loss of Cep192 did induce a substantial increase in the percentage of cells in which the mother and daughter centrioles became disengaged by metaphase (25% versus 5% in the control, Figure S3B). This disengagement normally occurs in telophase and is regulated by the anaphase promoting complex (APC) [S1]. We observed a similar effect after the depletion of g-tubulin, consistent with earlier reports that centriole engagement requires the presence of an intact PCM [S2, S3].

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