Ates (red) and DAPI (blue). The cell edges are outlined by a dashed line. Taken from [243].Cells 2021, ten,17 ofThus, Sun1 and Kif9 are likely to type a complicated. It’s feasible that microtubule binding by the Kif9 motor domain coupled to its microtubule depolymerizing activity exerts a pulling force around the centrosome, bringing it closer towards the nucleus. A direct interaction amongst Sun1 and also a kinesin will be without the need of precedent, but an indirect interaction of Sun1 with kinesin-1 through a KASH-domain protein is nicely established in many species [244]. Kinesins are not the only motor proteins involved in centrosome/nucleus attachment. Dynein as well is linked to KASH domain proteins in yeasts, animals and most likely also in Tridecanedioic acid web Dictyostelium [244]. This can be primarily based around the observation that a hypomorphic mutation within the dynein regulator Lis1 causes centrosome detachment from the nucleus [103]. Dynein could function together with Kif9 to bring the centrosome close for the nucleus by means of its microtubule minus-end directed motor activity. No matter if and how Lis1 and dynein interact with Sun1 in this context is just not identified. In spite of the tight relationship among the Dictyostelium centrosome and Sun1, the Sun1 binding partners in the centrosome are nonetheless unknown. Presently there are actually three candidates based on observed mutant phenotypes, i.e., the corona proteins CP248, CP148 and CenB. CP248 have to be somehow associated to Sun1 due to the fact localizations of Sun1 and, interestingly, also interaptin at the nuclear envelope are each reduced in CP248 knockout cells [57]. A function of CP148 in centrosome/nucleus attachment was proposed primarily based around the observation that in CP148 RNAi cells, centrosomes were regularly discovered detached in the nucleus [50]. A comparable phenotype was also observed upon knockout of centrin B [116]. Yet, in all these cases it remains elusive how these proteins are employed in centrosome/nucleus attachment. The fact that the centrosome remains nucleus connected even just after loss from the corona in prophase, may also indicate a role of core layer proteins in centrosome/nucleus attachment. five. Conclusions Analysis into the Dictyostelium centrosome during the final twenty-five years has revealed a fairly detailed picture of its structure, organization and dynamics. As anticipated for this ancient organelle, numerous similarities together with the various centrosome types of animals and fungi emerged, especially regarding the organization of microtubule nucleation complexes along with the proteins involved. On the other hand, as reflected also by structural variations, most prominently the lack of centrioles, you’ll find clear variations in centrosome duplication and its regulation. Comparative research of centriole-containing vs. acentriolar Dictyostelium centrosomes nicely revealed quite a few basic, centriole-independent functions, including not simply microtubule organization, but additionally cytokinesis and Golgi function. Future directions will concentrate on the elucidation on the centrosome’s role in nuclear envelope dynamics through semi-closed mitosis, and around the nonetheless not properly understood regulation of the dynamic processes throughout its duplication.Author Contributions: Conceptualization and primary writer, R.G.; text contributions, M.G., I.M., K.M. and V.P. All authors have study and agreed to the published version on the manuscript. Funding: This perform was Nimbolide Description funded by the Deutsche Forschungsgemeinschaft (DFG); grant GR1642/9-1, GR1642/11-1 to R.G. and ME3690/2-1 to I.M. Acknowledgments: We cordially acknowledge Alexandra Lepi.
