title: Ribosomal protein S3 localizes on the mitotic spindle and functions as a microtubule associated protein in mitosis.
abstract: The human ribosomal protein S3 (rpS3) has multi-functions such as translation, DNA repair and apoptosis. These multiple functions are regulated by post-translational modifications including phosphorylation, methylation and sumoylation. We report here a novel function of rpS3 that is involved in mitosis. When we examined localization of ribosomal proteins in mitosis, we found that rpS3 specifically localizes on the mitotic spindle. Depletion of the rpS3 proteins caused mitotic arrest during the metaphase. Furthermore, the shape of the spindle and chromosome movement in the rpS3 depleted cell was abnormal. Microtubule (MT) polymerization also decreased in rpS3 depleted cells, suggesting that rpS3 is involved in spindle dynamics. Therefore, we concluded that rpS3 acts as a microtubule associated protein (MAP) and regulates spindle dynamics during mitosis.
authors.affiliation: Laboratory of Biochemistry, School of Life Sciences and Biotechnology, Korea University, Seoul 136-701, Republic of Korea.
authors.forename: Chang-Young
authors.initials: CY
authors.lastname: Jang
authors.forename: Hag Dong
authors.initials: HD
authors.lastname: Kim
authors.forename: Xianghua
authors.initials: X
authors.lastname: Zhang
authors.forename: Jin-Soo
authors.initials: JS
authors.lastname: Chang
authors.forename: Joon
authors.initials: J
authors.lastname: Kim
mesh_terms: D043171:Chromosomal Instability; D006367:HeLa Cells; D006801:Humans; D008869:Microtubule-Associated Proteins / Q000378:metabolism*; D008870:Microtubules / Q000378:metabolism*; D008938:Mitosis; D058105:Polymerization; D012269:Ribosomal Proteins / Q000378:metabolism*; D008941:Spindle Apparatus / Q000378:metabolism*
chemical_list: D008869:Microtubule-Associated Proteins; D012269:Ribosomal Proteins; C044152:ribosomal protein S3