Record ID No. |
545 |
Author(s) |
Uchiumi T., Shimoda Y., Tsuruta T., Mukoyoshi Y., Suzuki A., Senoo K., Sato S., Kato T., Tabata S., Higashi S., Abe M , 2002 |
Affiliation |
Kagoshima University, Dept Chem & BioSci, Kagoshima 8900065, JAPAN |
Title |
Expression of symbiotic and nonsymbiotic globin genes responding to microsymbionts on Lotus japonicus |
Source. Vol.(no):Page |
Plant and Cell Physiology, 43(11): 1351-1358p. |
Categories |
Arbuscular Mycorrhiza |
Subjects |
Genetics |
Host |
Lotus japonicus,Medicagosativa |
Organism |
Glomus sp |
Country |
Japan, Asia |
Abstracts |
Leguminous plants have both symbiotic and nonsymbiotic hemoglobin (sym- and nonsym-Hb) genes. Three symbiotic (LjLb1, 2, 3) and one nonsymbiotic (LjNSG1) Hb genes were isolated from
a genomic library of Lotus japonicus MG20 Miyakojima. Two motif
sequences (AAAGAT and CTCTT) critical for nodule specific
expression were conserved on the 5'-upstream sequence of LjLb1,
2 and 3. The 5'-upstream region of LjNSG1 contained the sequence
consensus for nonsym-Hb. RT-PCR with specific primer sets for
each LjLb gene showed that all the sym-Hb genes (LjLb1, 2, 3)
were expressed specifically and strongly in root nodules. The
expression of LjLb1, 2 and 3 could not be detected in root, leaf
or stem of a mature plant, whereas low level expression was
detected in seedlings by RT-PCR. This suggests that sym-Hbs may
have another unknown function besides being oxygen transporter
for the microsymbiont in symbiotic nitrogen fixation. The
expression of LjNSG1, examined with RT-PCR, was detected at low
level in root, leaf and stem. The expression of LjNSG1 was
enhanced in root nodules, whereas it was repressed in roots
colonized by mycorrhizal fungi Glomus sp. R10. The repression of
the nonsym-Hb gene was also observed in the roots of Medicago
sativa colonized by Glomus sp. R10.
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