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Hannaford, M. R.

Publications and source records attributed to Hannaford, M. R..

2 recordsLinked to original sources

Pericentrin is a Kinesin-1 Activator that Drives Centriole Motility

Centrosome positioning is essential for their function. Typically, centrosomes are transported to various cellular locations through the interaction of centrosome nucleated microtubules with motor proteins. However, it remains unknown how centrioles migrate in cellular contexts in which centrioles do not nucleate microtubules. Here, we demonstrate that during interphase inactive centrioles move directly along the non-centrosomal microtubule network as cargo for the motor protein Kinesin-1. We identify Pericentrin-Like-Protein (PLP) as a novel Kinesin-1 interacting molecule essential for centriole motility. PLP directly interacts with the cargo binding domain of Kinesin-1 and they comigrate on microtubules in vitro. Finally, we demonstrate that PLP-Kinesin-1 dependent transport is essential for centrosome asymmetry age-dependent centrosome inheritance in asymmetric stem cell division.

cell biology↗

Requirement of the Dynein-adaptor Spindly for mitotic and post-mitotic functions in Drosophila

Spindly is a mitotic checkpoint protein originally identified as a specific regulator of Dynein activity at the kinetochore. In metaphase, Spindly recruits the Dynein/Dynactin complex, promoting the establishment of stable kinetochore-microtubule interactions and progression into anaphase. While details of Spindly function in mitosis have been worked out in cultured human cells and in the C. elegans zygote, the function of Spindly within the context of an organism has not yet been addressed. Here we present loss- and gain-of-function studies of Spindly in Drosophila. We investigated the requirements of distinct protein domains for the localisation and function of Spindly. We find that knock-down of Spindly results in a range of mitotic defects in the female germ line and during cleavage divisions in embryogenesis. Overexpression of Spindly in the female germ line is embryonic lethal and results in altered egg morphology. To determine whether Spindly plays a role in post-mitotic cells we altered Spindly protein levels in migrating cells and found that ovarian border cell migration is sensitive to the levels of Spindly protein. Our study uncovers novel functions of the mitotic checkpoint protein Spindly in Drosophila.

cell biology↗