Correction

BIOCHEMISTRY. For the article “HuR binding to cytoplasmic mRNA is perturbed by heat shock,” by Imed-Eddine Gallouzi, Christopher M. Brennan, Myrna G. Stenberg, Maurice S. Swanson, Ashley Eversole, Nancy Maizels, and Joan A. Steitz, which appeared in number 7, March 28, 2000, of Proc. Natl. Acad. Sci. USA (97, 3073–3078), the authors note the following regarding Fig. 2. Attempts to repeat in situ hybridization experiments comparing the localization of poly(A)⁺ RNA in HeLa cells before and after heat shock have revealed that the differences are not as dramatic as those seen in panels 13 and 14. Rather, the nearly complete absence of poly(A)⁺ RNA from the nuclear region is observed only in metaphase cells, which were mistakenly selected for display in panel 13. In nondividing cells at 37°C, a significant poly(A)⁺ signal is usually seen in the nucleus in addition to that in the cytoplasm. The major conclusions of the paper remain unchanged.