Sentences with word «anaphase»
Anaphase is a stage in cell division when the chromosomes separate and move to opposite ends of the cell. Full definition
The close temporal association of the [Ca2 +] i transient with the onset of anaphase suggests that calcium may have a signaling role in this event.
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«Cortical Dynein and Asymmetric Membrane Elongation Coordinately Position the Spindle in Anaphase»
In about 31 % of the cells, the protein motor dynein pulled an off - center spindle toward the middle of the cell during anaphase, correcting its position.
Despite this hard work from dynein, in roughly one - quarter of the cells observed, the spindle was misaligned, even after the paired chromosomes were pulled to opposite sides of the cell in late anaphase.
The role of DNA topology in holding sister chromatids together before anaphase was investigated by analyzing the structure of a small circular minichromosome in cell cycle (cdc) mutants of the yeast Saccharomyces cerevisiae.
Cells with proper spindle alignment in early anaphase (left) do not undergo this correction.
Therefore, sister minichromosome molecules need not remain topologically interlocked until anaphase in order to be properly segregated, and topological interlocking of sister DNA molecules apparently is not the primary force holding sister chromatids together.
Kiyomitsu's latest work focuses on the next step of mitosis, called anaphase, when the microtubules tear the paired chromosomes apart so that one copy of each chromosome ends up in each of the new daughter cells.
Such perfect division depends on the position of the mitotic spindle (chromosomes, microtubules, and spindle poles) within the cell, and it's now clear that human cells employ two specific mechanisms during the portion of division known as anaphase to correct mitotic spindle positioning.
Some cells with an apparently normal metaphase plate were unable to progress towards anaphase, instead entering into the process of cell death directly from mitosis (Figure 6H, bottom panel; Video 3).
In approximately 43 % of the dividing human cells Kiyomitsu observed, the middle of the mitotic spindle was properly centered at the beginning of anaphase.
However, mitotic cells showed a rapid elevation of [Ca2 +] i from basal levels of 130 nM to 500 to 800 nM at the metaphase - anaphase transition.
As you can see, during the 24 hours of a typical mammalian cell cycle, cohesin is pretty much always directly associated with the entire genome (the exceptions being chromosomes arms during most of mitosis, i.e. 20 - 40 minutes and entire chromatids during anaphase, i.e. ~ 10 minutes).
In roughly one - quarter of dividing human cells observed by Tomomi Kiyomitsu, a postdoctoral researcher in Whitehead Institute Member Iain Cheeseman's lab, the spindle was misaligned during mitosis, even after the paired chromosomes were pulled to opposite sides of the cell in late anaphase.
In the majority of cells arrested after S phase but before anaphase, sister minichromosome molecules are not topologically interlocked with each other.
In telomeric DNA mutants of Tetrahymena thermophila, created by expression of a telomerase RNA with an altered template sequence, division of the germline nucleus was severely delayed or blocked in anaphase.
Prior studies by Kerr el al, showed that PP2ACdc55 played an essential role in controlling the timing of metaphase to anaphase during meiosis, in other words preventing cells from prematurely exiting meiosis.
As seen in this merged fluorescent image (early anaphase marked with magenta; late anaphase marked with green), such cells correct this problem by adjusting their cell membranes relative to the spindle (right), instead of shifting their spindles within the cell.
Kim, Jung - Sik, et al. «Intact cohesion, anaphase, and chromosome segregation in human cells harboring tumor - derived mutations in STAG2.»
Martin Schwickart (Zachariae, MPG)-- «Molecular analysis of novel subunits of the anaphase - promoting complex (APC / C) in yeast» (2005)
Zuzana Markova (Zachariae, MPG)-- «Regulation of Meiotic Prophase by the Anaphase - Promoting Complex» (2012)
Tobias Oelschlaegel (Zachariae, MPG)-- «Meiosis - specific regulations of the anaphase - promoting complex» (2006)
Mutual antagonism between the anaphase promoting complex and the spindle assembly checkpoint contributes to mitotic timing in Caenorhabditis elegans
We often think of the human chromosomes as linear, anaphase - type bodies, a notion reinforced by the graphical depiction of chromosomes as linear two - dimensional objects on, say, the UCSC genome browser.
This not only ensures that sister chromatids remain cohesed until the metaphase - to - anaphase transition, but also provides us with the stereotypical image of an X-shaped chromosome.