Oocyte microtubules show their bias

submitted by: JCB
Several mRNAs are specifically transported to the anterior and posterior regions of Drosophila oocytes by microtubule-based motor proteins, but the organization of microtubules in these cells is unclear. Parton et al. reveal that oocyte microtubules are highly dynamic and display a PAR-1-dependent bias in polarity that facilitates transport of oskar mRNA to the oocyte posterior. This biosights episode presents the paper by Parton et al. from the July 11, 2011, issue of The Journal of Cell...

DNA replication times the cell cycle and contributes to the mid-blastula transition in Drosophila embryos

submitted by: JCB
We examined the contribution of S phase in timing cell cycle progression during Drosophila embryogenesis using an approach that deletes S phase rather than arresting its progress. Injection of Drosophila Geminin, an inhibitor of replication licensing, prevented subsequent replication so that the following mitosis occurred with uninemic chromosomes, which failed to align. The effect of S phase deletion on interphase length changed with development. During the maternally regulated syncytial...
Authors: Ml Mccleland, Aw Shermoen, Ph O'farrell