PLANT PHYSIOLOGY , Vol 101, Issue 1 259-265, Copyright © 1993 by American Society of Plant Biologists
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MOLECULAR BIOLOGY AND GENE REGULATION |
Expression of DcPRP1 Is Linked to Carrot Storage Root Formation and Is Induced by Wounding and Auxin Treatment
W. Ebener, T. J. Fowler, H. Suzuki, J. Shaver and M. L. Tierney
Agronomy Department, Ohio Agricultural Research and Development Center and Biotechnology Center, Ohio State University, Columbus, Ohio 43210
A carrot (Daucus carota, L.) genomic clone (DcPRP1) was isolated on the
basis of its homology to previously described cDNAs encoding a
wound-inducible, proline-rich cell wall protein. DNA sequence analysis
showed that DcPRP1 contains a single open-reading frame encoding a
235-amino acid protein that is colinear with that predicted from the cDNA
sequence with the exception of four amino acids at the N terminus and a
60-nucleotide insertion present within the genomic clone. Genomic Southern
hybridization analysis showed that the cloned sequence hybridized with a
single restriction enzyme fragment using several restriction enzymes.
Primer extension and northern hybridization analysis indicated that the
expression of DcPRP1 is developmentally regulated and linked to the
formation of storage roots, where this gene is expressed at high levels
after wounding. The level of DcPRP1 mRNA was greatest in tissue immediately
adjacent to the wound site. Treatment of unwounded carrot storage roots
with 10 [mu]M 2,4-dichlorophenoxy-acetic acid, indoleacetic acid, or
naphthalene-1-acetic acid also resulted in the accumulation of DcPRP1
transcripts to a level equal to that seen in wounded tissue.
