The requirement for the dam1 complex is dependent upon the number of kinetochore proteins and microtubules

Laura S. Burrack, Shelly E. Applen, Judith Berman

Research output: Contribution to journalArticlepeer-review

Abstract

The Dam1 complex attaches the kinetochore to spindle microtubules and is a processivity factor in vitro [1, 2]. In Saccharomyces cerevisiae, which has point centromeres that attach to a single microtubule, deletion of any Dam1 complex member results in chromosome segregation failures and cell death [3-5]. In Schizosaccharomyces pombe, which has epigenetically defined regional centromeres that each attach to 3-5 kinetochore microtubules, Dam1 complex homologs are not essential [6]. To determine why the complex is essential in some organisms and not in others, we used Candida albicans, a multimorphic yeast with regional centromeres that attach to a single microtubule [7]. Interestingly, the Dam1 complex was essential in C. albicans, suggesting that the number of microtubules per centromere is critical for its requirement. Importantly, by increasing CENP-A expression levels, more kinetochore proteins and microtubules were recruited to the centromeres, which remained fully functional. Furthermore, Dam1 complex members became less crucial for growth in cells with extra kinetochore proteins and microtubules. Thus, the requirement for the Dam1 complex is not due to the DNA-specific nature of point centromeres. Rather, the Dam1 complex is less critical when chromosomes have multiple kinetochore complexes and microtubules per centromere, implying that it functions as a processivity factor in vivo as well as in vitro.

Original languageEnglish
Pages (from-to)889-896
Number of pages8
JournalCurrent biology : CB
Volume21
Issue number10
DOIs
StatePublished - 24 May 2011
Externally publishedYes

Fingerprint

Dive into the research topics of 'The requirement for the dam1 complex is dependent upon the number of kinetochore proteins and microtubules'. Together they form a unique fingerprint.

Cite this