Spindle fibers form during prophase through a process called polymerization. This involves the assembly of protein subunits called tubulin into long filaments, which make up the spindle fibers.
The formation of spindle fibers is triggered by the breakdown of the nuclear membrane and the activation of a protein complex called the mitotic spindle assembly checkpoint. This checkpoint ensures that all chromosomes are properly attached to the spindle fibers before cell division can proceed.
The main function of spindle fibers during prophase is to help separate the duplicated chromosomes into two daughter cells during cell division. They also play a role in maintaining the structure and stability of the cell during this process.
Spindle fibers are different from other cytoskeletal fibers (such as microtubules and actin filaments) in terms of their structure and function. They are only present during cell division and are responsible for separating chromosomes, whereas other cytoskeletal fibers are involved in various cellular processes such as cell movement and shape maintenance.
Yes, there are several diseases and disorders associated with spindle fibers. For example, defects in spindle fiber formation can lead to chromosomal instability and may contribute to the development of cancer. Additionally, genetic mutations in the proteins that make up spindle fibers can result in conditions such as primary ciliary dyskinesia and primary microcephaly.