Close-up Drawing of DNA Structure July 23, 2009 By John Sopko This drawing shows the form DNA takes when it is between the microtubule (green) end and a gap from which a loop extends. The microtubule is attached to the DNA by the kinetochore structure (pink), which is 80 nm long. The kinetochore attaches to the DNA (yellow) at a hook-like space near the cse4 nucleosome (shown at the end). There are 55 histones (orange) on each of the “top” and “bottom” of the structure. Roughly 75% of the length of the DNA strand is tangled in “loop” structures, and the other 25% is between loops in a straighter line. Condensin (blue) binds to the DNA at the bottoms of the loops. Condensin (purple) wraps around and encloses the DNA within the loops and where there is a space on the far right. The small green asterisks show where the GFPs are placed on cohesin and condensin in the lab. Comments are closed.