It is critical to elucidate the pathways that mediate spindle assembly and therefore ensure accurate chromosome segregation during cell division. Our studies of a unique allele of the budding yeast Ipl1/Aurora protein kinase revealed that it is required for centrosome-mediated spindle assembly in the absence of the BimC motor protein Cin8. In addition, we found that the Ase1 spindle midzone-associated protein is required for bipolar spindle assembly. The cin8 ipl1 and cin8 ase1 double mutant cells exhibit similar defects, and Ase1 overexpression completely restores spindle assembly in cin8 ipl1 strains. Consistent with the possibility that Ipl1 regulates Ase1, an ase1 mutant lacking the Ipl1 consensus phosphorylation sites cannot assemble spindles in the absence of Cin8. In addition, Ase1 phosphorylation and localization were altered in an ipl1 mutant. We therefore propose that Ipl1/Aurora and Ase1 constitute a previously unidentified spindle assembly pathway that becomes essential in the absence of Cin8.
Download full-text PDF |
Source |
|---|---|
| http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2679386 | PMC |
| http://dx.doi.org/10.1016/j.devcel.2007.07.003 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
NME7 maintains primary cilium assembly, ciliary microtubule stability, and Hedgehog signaling.
Life Sci Alliance
April 2025
https://ror.org/0040axw97 Yunnan Key Laboratory of Cell Metabolism and Diseases, State Key Laboratory for Conservation and Utilization of Bio-Resources in Yunnan, Center for Life Sciences, School of Life Sciences, Yunnan University, Kunming, China
NME7 (nucleoside diphosphate kinase 7), a lesser studied member of the non-metastatic expressed (NME) family, has been reported as a potential subunit of the γ-tubulin ring complex (γTuRC). However, its role in the cilium assembly and function remains unclear. Our research demonstrated that NME7 is located at the centrosome, including at the spindle poles during metaphase and at the basal bodies during cilium assembly.
View Article and Find Full Text PDFDiverse microtubule-binding repeats regulate TPX2 activities at distinct locations within the spindle.
J Cell Biol
March 2025
State Key Laboratory of Oral and Maxillofacial Reconstruction and Regeneration, Key Laboratory of Oral Biomedicine Ministry of Education, Hubei Key Laboratory of Stomatology, School and Hospital of Stomatology, Medical Research Institute, Wuhan University, Wuhan, China.
TPX2 is an elongated molecule containing multiple α-helical repeats. It stabilizes microtubules (MTs), promotes MT nucleation, and is essential for spindle assembly. However, the molecular basis of how TPX2 performs these functions remains elusive.
View Article and Find Full Text PDFMaternal ELL3 loss-of-function leads to oocyte aneuploidy and early miscarriage.
Nat Struct Mol Biol
January 2025
Key Laboratory of Developmental Genes and Human Disease, School of Life Science and Technology, Southeast University, Nanjing, China.
Up to an estimated 10% of women experience miscarriage in their lifetimes. Embryonic aneuploidy is a leading cause for miscarriage, infertility and congenital defects. Here we identify variants of ELL3, a gene encoding a transcription elongation factor, in couples who experienced consecutive early miscarriages due to embryonic aneuploidy.
View Article and Find Full Text PDFInsufficient MIRO1 contributes to declined oocyte quality during reproductive aging.
Sci China Life Sci
January 2025
College of Animal Science and Technology, Nanjing Agricultural University, Nanjing, 210095, China.
Mitochondrial Rho-GTPase 1 (MIRO1) is an outer mitochondrial membrane protein which regulates mitochondrial transport and mitophagy in mitosis. In present study, we reported the crucial roles of MIRO1 in mammalian oocyte meiosis and its potential relationship with aging. We found that MIRO1 expressed in mouse and porcine oocytes, and its expression decreased in aged mice.
View Article and Find Full Text PDFThe dependence of shugoshin on Bub1-kinase activity is dispensable for the maintenance of spindle assembly checkpoint response in Cryptococcus neoformans.
PLoS Genet
January 2025
Molecular Mycology Laboratory, Molecular Biology and Genetics Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Bengaluru, India.
During chromosome segregation, the spindle assembly checkpoint (SAC) detects errors in kinetochore-microtubule attachments. Timely activation and maintenance of the SAC until defects are corrected is essential for genome stability. Here, we show that shugoshin (Sgo1), a conserved tension-sensing protein, ensures the maintenance of SAC signals in response to unattached kinetochores during mitosis in a basidiomycete budding yeast Cryptococcus neoformans.
View Article and Find Full Text PDFWant AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!