Cse4

Cse4, also known as CENP-A, is a histone H3 variant that plays a crucial role in the formation and function of the centromere in eukaryotic chromosomes. Centromeres are specialized regions of DNA that are essential for the accurate segregation of chromosomes during cell division. Unlike canonical histone H3, which is found throughout the genome, Cse4 is specifically localized to centromeric DNA. This unique localization allows it to act as a foundation for the assembly of the kinetochore, a protein complex that mediates the attachment of chromosomes to the spindle microtubules.

The incorporation of Cse4 into centromeric nucleosomes is a highly regulated process that occurs during cell division. This specialized histone is recognized by specific chaperones that facilitate its deposition onto centromeric DNA. The presence of Cse4 is critical for the proper epigenetic marking of centromeres, ensuring that they are recognized as distinct functional units by the cell. Disruptions in Cse4 function or localization can lead to chromosome mis-segregation, aneuploidy, and associated developmental abnormalities or diseases like cancer. Research into Cse4 continues to unravel its complex mechanisms of action and its implications for genome stability and cell cycle control.