Environ. Sci. Technol. 2007, 41, 4832
Response to Comment on “Conservation of Cancer Genes in the Marine Invertebrate Mytilus edulis” The Comment (1) highlights a discrepancy in gene sequences, both labeled p53, in Mytilus species, and attributes it to experimental technique. Instead, however, this discrepancy may raise important issues of nomenclature. There is by now a large body of invertebrate sequences on GenBank labeled as p53 and with strong homologies to each other. The genes in this grouping appear largely to have inherited the labeling of p53 from each other as the number of sequences on GenBank has built up. However, when these genes are compared (using BLAST) with well-established vertebrate sequences, the leading scores are to vertebrate p63 genes. From this perspective, the consistency of nomenclature in GenBank would arguably be improved if the entire body of invertebrate genes currently labeled as p53 were instead labeled as p63- or p53-like, rather than definitively p53. At best, their identification as p53 should be regarded as provisional. It is also worth noting explicitly that many of the invertebrate “p53/p63” sequences available on GenBank at the time our manuscript was published (2005) were obtained by an extended collaborative grouping of researchers, prob-
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ably using similar approaches and primers. The close correspondence among those sequences is therefore unsurprising. It is against this backdrop that we have isolated a Mytilus edulis gene fragment which shows considerably better alignment with established vertebrate p53 genes than those of Muttray et al. (2). While we have presented this finding in a factual way in order to allow the community to draw their own conclusions, a plausible interpretation is that our gene is a segment of the Mytilus p53 gene, and that other reported genes are the counterparts of the vertebrate p63 gene.
Literature Cited (1) Muttray, A. F.; Baldwin, S. A. Comment on “Conservation of Cancer Genes in the Marine Invertebrate Mytilus edulis”. Environ. Sci. Technol. 2007, 41, xxxx-xxxx. (2) Muttray, A. F.; Cox, R. L.; St-Jean, S. D.; van Poppelen, P.; Reinisch, C. L. Identification and phylogenetic comparison of p53 in two distinct mussel species (Mytilus). Comput. Biochem. Physiol., Part C: Pharmacol., Toxicol. Endocrinol. 2005, 140, 237-250.
Jeanette M. Rotchell* and Corina M. Ciocan Department of Biology & Environmental Science University of Sussex Falmer, Brighton, U.K. ES0709627
10.1021/es0709627 CCC: $37.00
2007 American Chemical Society Published on Web 06/06/2007
