PreprintArticleVersion 1Preserved in Portico This version is not peer-reviewed
Cyclin B Export to the Cytoplasm via the Nup62 Subcomplex and Its Subsequent Rapid Nuclear Import Are Required for the Initiation of Drosophila Male Meiosis
Yamazoe, K.; Inoue, Y.H. Cyclin B Export to the Cytoplasm via the Nup62 Subcomplex and Subsequent Rapid Nuclear Import Are Required for the Initiation of Drosophila Male Meiosis. Cells2023, 12, 2611.
Yamazoe, K.; Inoue, Y.H. Cyclin B Export to the Cytoplasm via the Nup62 Subcomplex and Subsequent Rapid Nuclear Import Are Required for the Initiation of Drosophila Male Meiosis. Cells 2023, 12, 2611.
Yamazoe, K.; Inoue, Y.H. Cyclin B Export to the Cytoplasm via the Nup62 Subcomplex and Subsequent Rapid Nuclear Import Are Required for the Initiation of Drosophila Male Meiosis. Cells2023, 12, 2611.
Yamazoe, K.; Inoue, Y.H. Cyclin B Export to the Cytoplasm via the Nup62 Subcomplex and Subsequent Rapid Nuclear Import Are Required for the Initiation of Drosophila Male Meiosis. Cells 2023, 12, 2611.
Abstract
The cyclin-dependent kinase (Cdk) 1–cyclin B (CycB) complex plays critical roles in cell cycle regulation. Before Drosophila male meiosis, CycB is exported from the nucleus to the cytoplasm via the nuclear porin 62kD (Nup62) subcomplex in the nuclear pore complex. When this is inhibited, Cdk1 is not activated, and meiosis does not initiate. We investigated the mechanism that controls cellular localization and activation of Cdk1. Cdk1–CycB continuously shuttled into and out of the nucleus in the prolonged G2 phase before meiosis. Overexpression of CycB, but not that with nuclear localization signal sequences, rescued reduced cytoplasmic CycB and inhibition of meiosis in Nup62-silenced cells. Full-scale Cdk1 activation occurred in the nucleus shortly after its rapid nuclear entry. Cdk1-dependent centrosome separation did not occur in Nup62-silenced cells, while Cdk1 interacted with Cdk-activating kinase and Twine/Cdc25C in the nucleus of Nup62-silenced cells, suggesting the involvement of another suppression mechanism. Silencing of roughex rescued Cdk1 inhibition and initiated meiosis. Nuclear exports of Cdk1 ensured its escape from inhibition by cyclin-dependent kinase inhibitor. The complex reentered the nucleus via importin β at the onset of meiosis. We propose a model regarding the dynamics and activation mechanism of Cdk1–CycB to initiate male meiosis.
Biology and Life Sciences, Cell and Developmental Biology
Copyright:
This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
