A nucleolar protein RRS1 contributes to chromosome congression

Edited by Angel Nebreda

Received 7 March 2009; received in revised form 12 May 2009; accepted 15 May 2009. published online 22 May 2009.

Abstract

We report here the functional analysis of human Regulator of Ribosome Synthesis 1 (RRS1) protein during mitosis. We demonstrate that RRS1 localizes in the nucleolus during interphase and is distributed at the chromosome periphery during mitosis. RNA interference experiments revealed that RRS1-depleted cells show abnormalities in chromosome alignment and spindle organization, which result in mitotic delay. RRS1 knockdown also perturbs the centromeric localization of Shugoshin 1 and results in premature separation of sister chromatids. Our results suggest that a nucleolar protein RRS1 contributes to chromosome congression.

Abbreviations: RNAi, RNA interference, siRNA, small interfering RNA, GFP, green fluorescent protein, H3S10ph, phospho-histone H3 serine 10

Keywords: Nucleolar protein, RRS1, Aurora B, Sgo1, Centromeric cohesion, Chromosome congression

a Laboratory of Dynamic Cell Biology, Department of Biotechnology, Graduate School of Engineering, Osaka University, 2-1 Yamadaoka, Suita, 565-0871 Osaka, Japan

b National Institute of Genetics, 1111 Yata, Mishima, 411-8540 Shizuoka, Japan

Corresponding author. Fax: +81 6 6879 7442.

PII: S0014-5793(09)00406-2

doi:10.1016/j.febslet.2009.05.033

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