regulation of metaphase plate congression

Definition

Target type: biologicalprocess

Any process that modulates the rate, frequency, or extent of metaphase plate congression, the alignment of chromosomes at the metaphase plate, a plane halfway between the poles of the spindle. [GOC:ascb_2009, GOC:dph, GOC:tb]

Metaphase plate congression is a crucial step in mitosis, ensuring proper chromosome alignment before sister chromatid separation. This process involves a complex interplay of microtubule dynamics, motor proteins, and signaling pathways. Here's a detailed breakdown:

1. **Microtubule Attachment:** During prometaphase, microtubules emanating from spindle poles capture chromosomes at their kinetochores, the specialized protein complexes on centromeres.

2. **Kinetochore-Microtubule Dynamics:** Once attached, kinetochore microtubules exhibit dynamic instability, alternating between periods of growth and shrinkage. This dynamic behavior allows for chromosome movement and ensures proper bipolar attachment.

3. **Tension Sensing:** As microtubules attach to both sides of a chromosome, tension is generated. This tension is crucial for signaling proper bipolar attachment and preventing errors in chromosome segregation.

4. **Motor Proteins:** Motor proteins, particularly dynein and kinesin, play critical roles in chromosome movement. Dynein, located at the kinetochore, walks along microtubules towards the minus ends at the poles, pulling chromosomes towards the spindle poles. Kinesin, located at the spindle poles, pushes chromosomes away from the poles, contributing to congression.

5. **Microtubule Flux:** Microtubules undergo constant turnover, with subunits being added at the plus ends and removed at the minus ends. This flux, along with motor protein activity, helps to reposition chromosomes and maintain tension at kinetochores.

6. **Signaling Pathways:** Signaling pathways, such as the Aurora B kinase pathway, regulate microtubule dynamics and motor protein activity. These pathways ensure that chromosomes are properly attached and aligned on the metaphase plate.

7. **Congression Completion:** The congression process continues until all chromosomes are aligned at the metaphase plate, a central plane equidistant from the poles. This alignment is essential for proper chromosome separation in anaphase.

8. **Spindle Checkpoint:** The spindle checkpoint, a surveillance mechanism, ensures that all chromosomes are properly attached to the spindle before the cell progresses to anaphase. This checkpoint prevents aneuploidy (abnormal chromosome number) which can lead to cell death or developmental defects.'
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Proteins (1)

Compounds (3)