Sy. Yi et Bk. Hwang, MOLECULAR-CLONING AND CHARACTERIZATION OF A NEW BASIC PEROXIDASE CDNAFROM SOYBEAN HYPOCOTYLS INFECTED WITH PHYTOPHTHORA-SOJAE F-SP GLYCINES, Molecules and Cells, 8(5), 1998, pp. 556-564
Differential display techniques were used to isolate cDNA clones corre
sponding to genes which were expressed in soybean hypocotyls by Phytop
hthora sojae f.sp. glycines infection. With a partial cDNA clone C20CI
4 from the differential display PCR as a probe, a new basic peroxidase
cDNA clone, designated GMIPER1, was isolated from a cDNA library of s
oybean hypocotyls infected with P. sojae f.sp. glycines. Sequence anal
ysis revealed that the peroxidase clone encodes a mature protein of 35
,813 Da with a putative signal peptide of 27 amino acids in its N-term
inus. The amino acid sequence of the soybean peroxidase GMIPER1 is bet
ween 54-75% identical to other plant peroxidases including a soybean s
eed coat peroxidase. Southern blot analysis indicated that multiple co
pies of sequences related to GMIPER1 exist in the soybean genome. The
mRNAs corresponding to the GMIPER1 cDNA accumulated predominantly in t
he soybean hypocotyls infected with the incompatible race of P. sojae
f.sp. glycines, but were expressed at low levels in the compatible int
eraction. Soybean GMIPER1 mRNAs were not expressed in hypocotyls, leav
es, stems, and roots of soybean seedlings. However, treatments with et
hephon, salicylic acid or methyl jasmonate induced the accumulation of
the GMIPER1 mRNAs in the different organs of soybean. These results s
uggest that the GMIPER1 gene encoding a putative pathogen-induced pero
xidase may play an important role in induced resistance of soybean to
P. sojae f.sp. glycines and in response to various external stresses.