CELL BIOLOGY. For the article “Abnormal centrosome amplification in cells through the targeting of Ran-binding protein-1 by the human T cell leukemia virus type-1 Tax oncoprotein,” by Jean-Marie Peloponese, Jr., Kerstin Haller, Akiko Miyazato, and Kuan-Teh Jeang, which appeared in issue 52, December 27, 2005, of Proc. Natl. Acad. Sci. USA (102, 18974–18979; first published December 19, 2005; 10.1073/pnas.0506659103), the authors note that the following statement should be added to the Acknowledgments: “We thank Dr. Patrizia Lavia (National Research Council Center of Evolutionary Genetics, University of Rome) for the generous gift of the RanBP1HA plasmid.”