Abstract

NaCl treatment of tomato plants in hydroponic culture at concentrations as low as 50 mM resulted in enhanced accumulation of transcripts of TPX1, a full-length cDNA clone that we had isolated from a library of NaCl-treated tomato plants using a peroxidase-specific oligonucleotide probe. Although the overall amino acid sequence identity of TPX1 to other peroxidase genes was less than 45%, there was a very high degree of identity in all of the conserved domains. The deduced amino acid sequence included the presence of a N-terminal signal peptide but not the C-terminal extension present in peroxidases targeted to the vacuole. The mature protein has a theoretical pI value of 7.5. Transcripts that hybridized to TPX1 were detected only in the roots with higher levels of mRNA in epidermal and subepidermal cell layers. Isoelectric focusing of root extracts showed two major bands of peroxidase activity at pI 5.9 and 6.2. Both activities increased with salt treatment. Southern analysis indicated the presence of only a single TPX1 gene in tomato.

Full Text
Paper version not known

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.