orsófonalak

Orsófonalak, also known as spindle fibers, are protein structures essential for cell division. They play a critical role in the process of mitosis and meiosis, ensuring that chromosomes are accurately separated and distributed to daughter cells. These fibers are composed primarily of microtubules, which are polymers of tubulin proteins.

During the early stages of cell division, a structure called the centrosome duplicates and the two centrosomes migrate to opposite poles of the cell. From these centrosomes, the spindle fibers begin to form, radiating outwards. There are several types of spindle fibers. Kinetochore microtubules attach to specialized protein structures on the chromosomes called kinetochores. These fibers are responsible for pulling the chromosomes towards the poles. Polar microtubules, on the other hand, extend from opposite poles and overlap in the middle of the cell, contributing to the elongation of the cell during division. Astral microtubules radiate from the centrosomes towards the cell membrane, helping to anchor the spindle apparatus.

The precise assembly and disassembly of spindle fibers are tightly regulated by a complex network of motor proteins and signaling molecules. This dynamic process ensures that each daughter cell receives a complete and correct set of chromosomes. Errors in spindle formation or function can lead to aneuploidy, a condition where cells have an abnormal number of chromosomes, which can contribute to developmental disorders and cancer.