Regulation of cyclin A localization downstream of Par-1 function is critical for the centrosome orientation checkpoint in Drosophila male germline stem cells.

Autor: Yuan H; Life Sciences Institute, Center for Stem Cell Biology, University of Michigan, Ann Arbor, MI 48109-2216, USA., Chiang CY, Cheng J, Salzmann V, Yamashita YM
Jazyk: angličtina
Zdroj: Developmental biology [Dev Biol] 2012 Jan 01; Vol. 361 (1), pp. 57-67. Date of Electronic Publication: 2011 Oct 15.
DOI: 10.1016/j.ydbio.2011.10.010
Abstrakt: Male germline stem cells (GSCs) in Drosophila melanogaster divide asymmetrically by orienting the mitotic spindle with respect to the niche, a microenvironment that specifies stem cell identity. The spindle orientation is prepared during interphase through stereotypical positioning of the centrosomes. We recently demonstrated that GSCs possess a checkpoint ("the centrosome orientation checkpoint") that monitors correct centrosome orientation prior to mitosis to ensure an oriented spindle and thus asymmetric outcome of the division. Here, we show that Par-1, a serine/threonine kinase that regulates polarity in many systems, is involved in this checkpoint. Par-1 shows a cell cycle-dependent localization to the spectrosome, a germline-specific, endoplasmic reticulum-like organelle. Furthermore, the localization of cyclin A, which is normally localized to the spectrosome, is perturbed in par-1 mutant GSCs. Interestingly, overexpression of mutant cyclin A that does not localize to the spectrosome and mutation in hts, a core component of the spectrosome, both lead to defects in the centrosome orientation checkpoint. We propose that the regulation of cyclin A localization via Par-1 function plays a critical role in the centrosome orientation checkpoint.
(Copyright © 2011 Elsevier Inc. All rights reserved.)
Databáze: MEDLINE
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