neuroscience. For the article “Unique domain anchoring of Src to synaptic NMDA receptors via the mitochondrial protein NADH dehydrogenase subunit 2,” by Jeffrey R. Gingrich, Kenneth A. Pelkey, Sami R. Fam, Yueqiao Huang, Ronald S. Petralia, Robert J. Wenthold, and Michael W. Salter, which appeared in issue 16, April 20, 2004, of Proc. Natl. Acad. Sci.USA (101, 6237–6242; first published April 6, 2004; 10.1073/pnas.0401413101), the authors would like to note the following: “The antibody that we claimed to recognize the mitochondrial protein ND4, a control in our study, actually recognizes the mitochondrial protein NdufA9. Like ND4, NdufA9 protein has a molecular weight of 39 kDa and is a subunit of NADH dehydrogenase (complex I). But unlike ND4, NdufA9 is encoded in the nucleus. Because NdufA9 is a subunit of complex I, as is ND4, NdufA9 is an appropriate control for our study. Thus, the conclusions of our article remain unchanged. Each occurrence of ND4 should be replaced by NdufA9, in the text as well as in labels of Fig. 2 A and B.” The corrected figure and legend appear below. In addition, the authors note that on page 6239, the sixth sentence of the second full paragraph, left column, “In contrast to ND2, neither the oxidoreductase protein ND4, another mitochondrially encoded component of complex I (25–27), nor Cyto1, an inner mitochondrial membrane protein component of complex IV (30), was detectable in the PSD fraction,” should read: “In contrast to ND2, neither the oxidoreductase protein NdufA9, another component of complex I (25–27), nor Cyto1, an inner mitochondrial membrane protein component of complex IV (30), was detectable in the PSD fraction.” These errors do not affect the conclusions of the article.
Fig. 2.
ND2 is present at the PSD. (A) Immunoblots of PSD proteins probed with anti-ND2, anti-cytochrome c oxidase I (Cyto1), anti-NdufA9, anti-PSD95, anti-NR1, anti-Src, and anti-synaptophysin. The PSD preparation contained PSD95, NR1, and Src, but lacked the presynaptic marker synaptophysin. (B) Immunoblots of mitochondrial proteins probed with anti-ND2, anti-Cyto1, and anti-NdufA9. Neither NR1 nor NR2A/B was detected in the mitochondrial fraction (not shown). (C) Immunoblots of PSD proteins showing the specificity of the N-terminal ND2 antibody by preadsorption with the antigenic peptide used to derive the antibody. (D) Immunoblots of PSD and mitochondrial proteins probed with two independent rabbit polyclonal antibodies directed against two disparate regions of ND2. The N-terminal ND2 antibody was used for all subsequent experiments shown. (E) Postembedding immunogold electron microscopy images of rat hippocampus CA1 synapses. ND2 immunoreactivity in PSDs is visualized by secondary antibody conjugated to 10-nm gold particles. pre, presynaptic. (Scale bar is 200 nm.)