Henry-York Steiner, Wei Song, Larry Zhang, Fred Naider, Jeffrey M. Becker, and Gary Stacey (1994). An Arabidopsis Peptide Transporter Is a Member of a New Class of Membrane Transport Proteins. Plant Cell 6, 1289–1299.
Recent comparisons of the AtPTR2-A cDNA sequence to similar proteins in the database showed that this gene clearly falls into a group containing exclusively yeast and fungal genes. This led us to examine whether this cDNA was indeed derived from an Arabidopsis mRNA. Chromosomal DNA was isolated from ecotypes Columbia, Landsberg, Nossen-1, and Wassilewskija and digested with restriction enzymes EcoRI, HindIII, and BamHI. DNA gel blots containing this DNA were hybridized with a labeled AtPTR2-A cDNA. In repeated attempts, no hybridization was obtained. However, positive hybridization was obtained when the blots were probed with an AtPTR2-B gene probe. Therefore, we conclude from this analysis that AtPTR2-A does not represent a bona fide Arabidopsis gene. We believe that our original results were due to the presence of a common, unidentified fungal contaminant in the plants harvested for analysis. It is also likely that the presence of this common contaminant explains the presence of the AtPTR2-A cDNA in the gene library used in this work. In summary, AtPTR2-A is not a bona fide Arabidopsis gene but more likely is derived from a fungal contaminant. We regret any inconvenience that our mistake may have caused.