Mallik and Henikoff have posited the evolution of 
Mallik and Henikoff have posited the evolution of these structures from two-micron STB elements. These items are unable to self-associate properly in the absence of functional ESCO2, a condition known as Robert's syndrome. A common type of yeast vector combines this with an autonomous replicating sequence.  Shugoshin prevents the release of cohesin from these elements, and Cse4 is a H3 variant that loads at this site.  "Point" ones may bind only a single nucleosome and may be as small as 125 base pairs, but mammalian ones are much larger and contain repetitive alpha satellite DNA.  This DNA element is bound by Bub and Mad proteins during cell division.  For 10 points, name this DNA region, the site of kinetochore assembly and spindle attachment, which is often found at the central point of a chromosome.
Mallik and Henikoff have posited the evolution of these structures from two-micron STB elements.
centromeres (kinetochore is not acceptable at any point)