TY - JOUR
T1 - The requirement for the dam1 complex is dependent upon the number of kinetochore proteins and microtubules
AU - Burrack, Laura S.
AU - Applen, Shelly E.
AU - Berman, Judith
N1 - Funding Information: We would like to acknowledge Maryam Gerami-Nejad for assistance with strain construction and members of the Berman laboratory for many helpful discussions. We would also like to thank Meleah Hickman, Hung-Ji Tsai, Ben Harrison, Duncan Clarke, Tricia Davis, and members of the Davis laboratory for providing very useful feedback on the manuscript. This work is supported by a Ruth L. Kirschstein National Research Service Award Individual Fellowship F32 AI800742 to L.S.B., funding from the University of Minnesota Undergraduate Research Opportunity Program to S.E.A., and funding by National Institute of Health/National Institute of Allergy and Infectious Disease AI075096 to J.B.
PY - 2011/5/24
Y1 - 2011/5/24
N2 - 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.
AB - 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.
UR - http://www.scopus.com/inward/record.url?scp=79957461486&partnerID=8YFLogxK
U2 - https://doi.org/10.1016/j.cub.2011.04.002
DO - https://doi.org/10.1016/j.cub.2011.04.002
M3 - مقالة
SN - 0960-9822
VL - 21
SP - 889
EP - 896
JO - Current Biology
JF - Current Biology
IS - 10
ER -