The spindle checkpoint in plants - a green variation over a conserved theme?

The spindle checkpoint, also called spindle assembly checkpoint (SAC), is a crucial control instance in animals and yeast that surveys the correct attachment of chromosomes to the spindle assuring their equal distribution in mitosis and meiosis. The presence of homologs of all core SAC components in plants indicates that these regulators have an ancient function. However, the fact that mutants of SAC components in plants are usually fully viable together with the observation that plants can be readily made polyploid raises the question whether plants have an efficient SAC. Recently, the role and regulation of a putative SAC in plants has been addressed. Interestingly, these studies also revealed that SAC genes are involved in several other cellular and developmental processes outside of chromosome distribution control.