CLEM characterization of microtubules near Mad2-positive kinetochores during metaphase. (A) RPE1 cell with fully assembled metaphase plate and a single spot of Mad2-Venus (yellow spot superimposed on gray DIC image). (B) Mad2-Venus spot (arrow) corresponds with a single kinetochore. LM (left) and matching EM (right) sections at the same magnification. (C) Series of 80-nm sections through the Mad2-positive kinetochore. Yellow arrows point at short microtubules near the kinetochore. Blue arrows denote K-fiber attached to a different kinetochore (arrowheads) and passing near the mesh of short microtubules. (D) Superimposition of short microtubules (orange lines; traced in EM) on the LM image of the Mad2-positive kinetochore.