Kif2 localizes to a subdomain of cortical endoplasmic reticulum that drives asymmetric spindle position

Abstract

Asymmetric positioning of the mitotic spindle is a fundamental process responsible for creating sibling cell size asymmetry; however, how the cortex causes the depolymerization of astral microtubules during asymmetric spindle positioning has remained elusive. Early ascidian embryos possess a large cortical subdomain of endoplasmic reticulum (ER) that causes asymmetric spindle positioning driving unequal cell division. Here we show that the microtubule depolymerase Kif2 localizes to this subdomain of cortical ER. Rapid live-cell imaging reveals that microtubules are less abundant in the subdomain of cortical ER. Inhibition of Kif2 function prevents the development of mitotic aster asymmetry and spindle pole movement towards the subdomain of cortical ER, whereas locally increasing microtubule depolymerization causes exaggerated asymmetric spindle positioning. This study shows that the microtubule depolymerase Kif2 is localized to a cortical subdomain of endoplasmic reticulum that is involved in asymmetric spindle positioning during unequal cell division.

KIF2 mediates the neuroprotection in cerebral ischaemia injury by affecting NF‐κB pathway

“…KIF2 is a kinesin-like transcription factor that is expressed in various tissues, and is implicated in the regulation of inflammation, cell apoptosis and other physiological processes. 7,13 In the present study, we found that KIF2 expression is aberrantly…”

“…KIF2 is a kinesin‐like transcription factor that is expressed in various tissues, and is implicated in the regulation of inflammation, cell apoptosis and other physiological processes . Dysregulation of KIF2 expression has been identified to be associated with various pathological progression .…”

“…Like other KIF family members, KIF2 is also enriched at the centrosomes and centromeres/kinetochores . This is helpful to promote the formation of spindle and proper segregation of chromosome, and further correct the abnormal adhesion of microtubule to chromosome during mitosis, contributing to the survival of cells …”

“…Like other KIF family members, KIF2 is also enriched at the centrosomes and centromeres/kinetochores 6. This is helpful to promote the formation of spindle and proper segregation of chromosome, and further correct the abnormal adhesion of microtubule to chromosome during mitosis, contributing to the survival of cells 7,13,15. An increasing number of reports have demonstrated that the NF-κB pathway is also involved in the neuroprotection against various neurotoxins with different or even opposite effects.…”

Spatiotemporally controlled Myosin relocalization and internal pressure cause biased cortical extension to generate sibling cell size asymmetry

“…Drosophila male germline stem cells, generating an equal sized gonialblast and a self-renewed germline stem cell (Spradling et al, 2011), control spindle symmetry with the centrosomalassociated microtubule depolymerizing kinesin Klp10A (Kinesin 13 family); klp10A mutants contain unequal sized centrosomes, resulting in the formation of asymmetric spindles and unequal sized cell divisions (Chen et al, 2016). Similarly, ER localized Kif2A, a microtubule depolymerase, induces spindle asymmetry and positioning in ascidians (Costache et al, 2017). Since the anaphase spindle is the primary determinant for the positioning of the cleavage furrow (D'Avino et al, 2015;Glotzer, 2017;Green et al, 2012;Rappaport, 1986), spindle geometry can at least partially explain physical asymmetry.…”