NDC80 Protein Complex Responsible for Cell Division in Arabidopsis

Kinetochore, a protein super‐complex on the centromere of chromosomes, controls chromosome segregation during cell division. The NDC80 complex, made up of NDC80, NUF2, SPC24 and SPC25 proteins, connects spindle fibers to the kinetochore. While it is found in most species, functional studies of this complex are rare in Arabidopsis.

The team of Jinwoo Shin from Seoul National University in South Korea characterizes a recessive mutant, meristem unstructured‐1 (mun‐1), which exhibits an abnormal phenotype with unstructured shoot apical meristem caused by expression of the WUSCHEL gene in unexpected tissues. The mutant also exhibits stunted growth, embryo arrest, DNA aneuploidy, and defects in chromosome segregation with a low cell division rate.

Null mutants of MUN generated via TALEN and CRISPR-Cas9 techniques showed the same embryo lethality as mun-1 as well as with another recessive mutant, nuf2-1. Interactions of the components of the NDC80 complex were confirmed and that absence of any one of the four proteins involved would result in malfunction of kinetochore components.

These results reveal that MUN is a homolog of SPC24 in Arabidopsis, which is required for proper cell division.

For more information, read the article in The Plant Journal.