The principle of action of colchicine

Colchicine inhibits mitosis, destroys the spindle, and causes chromosomes to stagnate in the middle of the division. This abnormal division caused by colchicine is called colchicine mitosis (C-mitosis). In such mitosis, although the chromosome is split, the cells do not divide and cannot form two daughter cells, thereby doubling the chromosome.

Whether colchicine destroys or inhibits the formation of the spindle, the effect is temporary. Qiushui can inhibit the formation of the spindle, leading to the cell not dividing, and then metabolized by colchicine for a period of time, no longer functioning, the cells continue to divide, and then the "multiple chromosome numbers" (the division of the centromere) ).

The separation of the centromeres is independent of the spindle since the two monomers can also be separated in the case of treatment with colchicine and destruction of the microtubules. This is due to the induction of Ca ions, which separates the centromere and then moves from the spindle to the two poles, that is, the spindle only plays the role of pulling the chromosome.

It can be seen that the period of action of colchicine should be the early stage of cell mitosis. The centromere will split in the late stage of division, and the two chromatids are divided into two chromosomes. The role of the spindle is to pull the split chromosome to the two poles of the cell, then form a cell plate in the middle of the cell, and finally become two cells.

After the use of colchicine, the synthesis of the spindle is inhibited. After the late chromatid cleavage, there is no spindle and cannot be pulled toward the cell poles, so the cell plate is not formed, the cells are not split, and finally, the chromosome is formed. Double the cells.