Cell division is a regulated recurring process where each parent cell must divide and equally distribute its genome into two daughter cells. Faithful segregation of chromosomes during mitosis depends on a structure called the kinetochore. The kinetochore, which is a large proteinaceous structure, mediates the attachment between spindle microtubules and chromosomes to ensure successful cell division. However, the mechanism behind these interactions remains poorly understood. 

In this study, we investigated MPS1 (monopolar spindle 1), which is a kinase that localizes to the kinetochore and has been shown to be involved in error correction during mitotic progression. Error correction is a process that regulates the correct biorientation of chromosomes before the completion of mitosis. This is important to ensure that prior to the onset of anaphase, all chromosomes are lined up properly to minimize erroneous connections that can be detrimental to the cell. Although MPS1 activity has been documented as being important in error correction, how it is recruited and regulated at kinetochores remains unclear.  

SPC105 is an intrinsically disordered kinetochore protein that attaches chromosomes to spindle microtubules. Prior work from the lab has indicated that the central region of SPC105, which contains repeated amino acid sequences termed MEED motifs, is important for recruiting a population of MPS1 to the kinetochore that we propose is important for error correction. In conclusion, this study focuses on investigating the mechanism that drives the interaction between SPC105-MPS1 at the kinetochore.