Abstract
In Arabidopsis, spermine is produced in most tissues and has been implicated in stress response, while its structural isomer thermospermine is only in xylem precursor cells. Studies on acaulis5 (acl5), a mutant defective in the biosynthesis of thermospermine, have revealed that thermospermine plays a repressive role in xylem development through enhancement of mRNA translation of the SAC51 family. In contrast, the pao5 mutant defective in the degradation of thermospermine has high levels of thermospermine and shows increased salt tolerance, suggesting a role of thermospermine in salt stress response. Here we compared acl5 with a mutant of spermine synthase, spms, in terms of abiotic stress tolerance and found that acl5 was much more sensitive to sodium than the wild-type and spms. A double-mutant of acl5 and sac51-d, which suppresses the excessive xylem phenotype of acl5, recovered normal sensitivity, while a quadruple T-DNA insertion mutant of the SAC51 family, which has an increased thermospermine level but shows excessive xylem development, showed increased salt sensitivity, unlike pao5. Together with the result that the salt tolerance of both wild-type and acl5 seedlings was improved by long-term treatment with thermospermine, we suggest a correlation of the salt tolerance with reduced xylem development rather than with the thermospermine level. We further found that the mutants containing high thermospermine levels showed increased tolerance to drought and heat stress, suggesting another role of thermospermine that may be common with that of spermine and secondary to that in restricting excess xylem development associated with salt hypersensitivity.
| Original language | English |
|---|---|
| Pages (from-to) | 374-383 |
| Number of pages | 10 |
| Journal | Plant Journal |
| Volume | 100 |
| Issue number | 2 |
| DOIs | |
| Publication status | Published - Oct 1 2019 |
Fingerprint
Keywords
- Arabidopsis thaliana
- salt tolerance
- spermine
- thermospermine
- xylem
ASJC Scopus subject areas
- Genetics
- Plant Science
- Cell Biology
Cite this
Salt hypersensitivity is associated with excessive xylem development in a thermospermine-deficient mutant of Arabidopsis thaliana. / Shinohara, Shiori; Okamoto, Takashi; Motose, Hiroyasu; Takahashi, Taku.
In: Plant Journal, Vol. 100, No. 2, 01.10.2019, p. 374-383.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Salt hypersensitivity is associated with excessive xylem development in a thermospermine-deficient mutant of Arabidopsis thaliana
AU - Shinohara, Shiori
AU - Okamoto, Takashi
AU - Motose, Hiroyasu
AU - Takahashi, Taku
PY - 2019/10/1
Y1 - 2019/10/1
N2 - In Arabidopsis, spermine is produced in most tissues and has been implicated in stress response, while its structural isomer thermospermine is only in xylem precursor cells. Studies on acaulis5 (acl5), a mutant defective in the biosynthesis of thermospermine, have revealed that thermospermine plays a repressive role in xylem development through enhancement of mRNA translation of the SAC51 family. In contrast, the pao5 mutant defective in the degradation of thermospermine has high levels of thermospermine and shows increased salt tolerance, suggesting a role of thermospermine in salt stress response. Here we compared acl5 with a mutant of spermine synthase, spms, in terms of abiotic stress tolerance and found that acl5 was much more sensitive to sodium than the wild-type and spms. A double-mutant of acl5 and sac51-d, which suppresses the excessive xylem phenotype of acl5, recovered normal sensitivity, while a quadruple T-DNA insertion mutant of the SAC51 family, which has an increased thermospermine level but shows excessive xylem development, showed increased salt sensitivity, unlike pao5. Together with the result that the salt tolerance of both wild-type and acl5 seedlings was improved by long-term treatment with thermospermine, we suggest a correlation of the salt tolerance with reduced xylem development rather than with the thermospermine level. We further found that the mutants containing high thermospermine levels showed increased tolerance to drought and heat stress, suggesting another role of thermospermine that may be common with that of spermine and secondary to that in restricting excess xylem development associated with salt hypersensitivity.
AB - In Arabidopsis, spermine is produced in most tissues and has been implicated in stress response, while its structural isomer thermospermine is only in xylem precursor cells. Studies on acaulis5 (acl5), a mutant defective in the biosynthesis of thermospermine, have revealed that thermospermine plays a repressive role in xylem development through enhancement of mRNA translation of the SAC51 family. In contrast, the pao5 mutant defective in the degradation of thermospermine has high levels of thermospermine and shows increased salt tolerance, suggesting a role of thermospermine in salt stress response. Here we compared acl5 with a mutant of spermine synthase, spms, in terms of abiotic stress tolerance and found that acl5 was much more sensitive to sodium than the wild-type and spms. A double-mutant of acl5 and sac51-d, which suppresses the excessive xylem phenotype of acl5, recovered normal sensitivity, while a quadruple T-DNA insertion mutant of the SAC51 family, which has an increased thermospermine level but shows excessive xylem development, showed increased salt sensitivity, unlike pao5. Together with the result that the salt tolerance of both wild-type and acl5 seedlings was improved by long-term treatment with thermospermine, we suggest a correlation of the salt tolerance with reduced xylem development rather than with the thermospermine level. We further found that the mutants containing high thermospermine levels showed increased tolerance to drought and heat stress, suggesting another role of thermospermine that may be common with that of spermine and secondary to that in restricting excess xylem development associated with salt hypersensitivity.
KW - Arabidopsis thaliana
KW - salt tolerance
KW - spermine
KW - thermospermine
KW - xylem
UR - http://www.scopus.com/inward/record.url?scp=85073651038&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=85073651038&partnerID=8YFLogxK
U2 - 10.1111/tpj.14448
DO - 10.1111/tpj.14448
M3 - Article
C2 - 31257654
AN - SCOPUS:85073651038
VL - 100
SP - 374
EP - 383
JO - Plant Journal
JF - Plant Journal
SN - 0960-7412
IS - 2
ER -