Correction

NEUROBIOLOGY. For the article “Wild-type and mutated presenilins 2 trigger p53-dependent apoptosis and down-regulate presenilin 1 expression in HEK293 human cells and in murine neurons,” by Cristine Alves da Costa, Erwan Paitel, Marc P. Mattson, Robert Amson, Adam Telerman, Karine Ancolio, and Frédéric Checler, which appeared in number 6, March 19, 2002, of Proc. Natl. Acad. Sci. USA (99, 4043–4048), the authors note that the author name “Marc P. Mattson” should be “Mark P. Mattson.” The online version has been corrected.