Centroméry

Centromeres are specialized DNA sequences found on eukaryotic chromosomes. They play a crucial role in cell division by serving as the attachment point for spindle fibers. These fibers are responsible for segregating sister chromatids during mitosis and meiosis, ensuring that each daughter cell receives a complete set of chromosomes. The centromere region is typically characterized by repetitive DNA sequences and a unique histone variant called CENP-A, which forms the outer boundary of the centromere and serves as the foundation for the kinetochore. The kinetochore is a complex protein structure that assembles on the centromere and directly interacts with the spindle microtubules. Without functional centromeres, chromosomes would not be properly aligned and segregated, leading to aneuploidy, a condition where cells have an abnormal number of chromosomes, which can have severe consequences for the organism. The precise structure and function of centromeres can vary slightly between different species, but their fundamental role in chromosome segregation remains constant.