The nuclear mitotic apparatus (NuMA) protein: localization and dynamics in human oocytes, fertilization and early embryos

The formation and maintenance of the bipolar mitotic spindle apparatus require a complex and balanced interplay of several mechanisms, including the stabilization and separation of polar microtubules and the action of various microtubule motors. Nonmicrotubule elements are also present throughout the spindle apparatus and have been proposed to provide a structural support for the spindle. The Nuclear-Mitotic Apparatus protein (NuMA) is an abundant 240 kD protein that is present in the nucleus of interphase cells and concentrates in the polar regions of the spindle apparatus during mitosis. Sequence analysis indicates that NuMA possesses an unusually long alpha-helical central region characteristic of many filament forming proteins. In this report we demonstrate that microinjection of anti-NuMA antibodies into interphase and prophase cells results in a failure to form a mitotic spindle apparatus. Furthermore, injection of metaphase cells results in the collapse of the spindle apparatus into a monopolar microtubule array. These results identify for the first time a nontubulin component important for both the establishment and stabilization of the mitotic spindle apparatus in multicellular organisms. We suggest that nonmicrotubule structural components may be important for these processes.

Download Full-text

Nuclear-mitotic apparatus protein: a structural protein interface between the nucleoskeleton and RNA splicing.

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.91.4.1505 ◽

1994 ◽

Vol 91 (4) ◽

pp. 1505-1509 ◽

Cited By ~ 47

Author(s):

C. Zeng ◽

D. He ◽

S. M. Berget ◽

B. R. Brinkley

Keyword(s):

Rna Splicing ◽

Protein A ◽

Protein Interface ◽

Structural Protein ◽

Mitotic Apparatus ◽

Nuclear Mitotic Apparatus

Download Full-text

Resetting histone modifications during human parental-to-zygotic transition

Science ◽

10.1126/science.aaw5118 ◽

2019 ◽

Vol 365 (6451) ◽

pp. 353-360 ◽

Cited By ~ 36

Author(s):

Weikun Xia ◽

Jiawei Xu ◽

Guang Yu ◽

Guidong Yao ◽

Kai Xu ◽

...

Keyword(s):

Histone Modifications ◽

Histone H3 ◽

Lineage Specification ◽

Regulatory Regions ◽

Regulate Gene Expression ◽

Human Oocytes ◽

Priming Phase ◽

Repressive Mark ◽

Early Embryos ◽

Genome Activation

Histone modifications regulate gene expression and development. To address how they are reprogrammed in human early development, we investigated key histone marks in human oocytes and early embryos. Unlike that in mouse oocytes, the permissive mark trimethylated histone H3 lysine 4 (H3K4me3) largely exhibits canonical patterns at promoters in human oocytes. After fertilization, prezygotic genome activation (pre-ZGA) embryos acquire permissive chromatin and widespread H3K4me3 in CpG-rich regulatory regions. By contrast, the repressive mark H3K27me3 undergoes global depletion. CpG-rich regulatory regions then resolve to either active or repressed states upon ZGA, followed by subsequent restoration of H3K27me3 at developmental genes. Finally, by combining chromatin and transcriptome maps, we revealed transcription circuitry and asymmetric H3K27me3 patterning during early lineage specification. Collectively, our data unveil a priming phase connecting human parental-to-zygotic epigenetic transition.

Download Full-text