TY - JOUR
T1 - Identification of STOP1-like proteins associated with aluminum tolerance in sweet sorghum (Sorghum bicolor l.)
AU - Huang, Sheng
AU - Gao, Jie
AU - You, Jiangfeng
AU - Liang, Yanan
AU - Guan, Kexing
AU - Yan, Siqi
AU - Zhan, Meiqi
AU - Yang, Zhenming
N1 - Funding Information:
This work was supported by the National Natural Science Foundation of China (31572192 and 31701982) and the China Postdoctoral Science Foundation (2017M611327).
Publisher Copyright:
© 2018 Huang, Gao, You, Liang, Guan, Yan, Zhan and Yang.
PY - 2018/2/28
Y1 - 2018/2/28
N2 - Aluminum (Al) toxicity in acidic soils affects crop production worldwide. C2 H2 -type zinc finger transcription factor STOP1/ART1-mediated expression of Al tolerance genes has been shown to be important for Al resistance in Arabidopsis, rice and other crop plants. Here, we identified and characterized four STOP1-like proteins (SbSTOP1a, SbSTOP1b, SbSTOP1c, and SbSTOP1d) in sweet sorghum, a variant of grain sorghum (Sorghum bicolor L.). Al induced the transcription of the four SbSTOP1 genes in both time- and Al concentration-dependent manners. All SbSTOP1 proteins localized to the cell nucleus, and they showed transcriptional activity in a yeast expression system. In the HEK 293 coexpression system, SbSTOP1d showed transcriptional regulation of SbSTAR2 and SbMATE, indicating the possible existence of another SbSTOP1 and SbSTAR2-dependent Al tolerance mechanism in sorghum apart from the reported SbMATE-mediated Al exclusion mechanism. A transgenic complementation assay showed that SbSTOP1d significantly rescued the Al-sensitivity characteristic of the Atstop1 mutant. Additionally, yeast two-hybrid and bimolecular fluorescence complementation (BiFC) assays showed that SbSTOP1d interacted with SbSTOP1b and SbSTOP1d itself, suggesting that SbSTOP1 may function as a homodimer and/or heterodimer. These results indicate that STOP1 plays an important role in Al tolerance in sweet sorghum and extend our understanding of the complex regulatory mechanisms of STOP1-like proteins in response to Al toxicity.
AB - Aluminum (Al) toxicity in acidic soils affects crop production worldwide. C2 H2 -type zinc finger transcription factor STOP1/ART1-mediated expression of Al tolerance genes has been shown to be important for Al resistance in Arabidopsis, rice and other crop plants. Here, we identified and characterized four STOP1-like proteins (SbSTOP1a, SbSTOP1b, SbSTOP1c, and SbSTOP1d) in sweet sorghum, a variant of grain sorghum (Sorghum bicolor L.). Al induced the transcription of the four SbSTOP1 genes in both time- and Al concentration-dependent manners. All SbSTOP1 proteins localized to the cell nucleus, and they showed transcriptional activity in a yeast expression system. In the HEK 293 coexpression system, SbSTOP1d showed transcriptional regulation of SbSTAR2 and SbMATE, indicating the possible existence of another SbSTOP1 and SbSTAR2-dependent Al tolerance mechanism in sorghum apart from the reported SbMATE-mediated Al exclusion mechanism. A transgenic complementation assay showed that SbSTOP1d significantly rescued the Al-sensitivity characteristic of the Atstop1 mutant. Additionally, yeast two-hybrid and bimolecular fluorescence complementation (BiFC) assays showed that SbSTOP1d interacted with SbSTOP1b and SbSTOP1d itself, suggesting that SbSTOP1 may function as a homodimer and/or heterodimer. These results indicate that STOP1 plays an important role in Al tolerance in sweet sorghum and extend our understanding of the complex regulatory mechanisms of STOP1-like proteins in response to Al toxicity.
KW - Al tolerance genes
KW - Aluminum toxicity
KW - STOP1
KW - Sweet sorghum
KW - Transcriptional regulation
UR - http://www.scopus.com/inward/record.url?scp=85043376092&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=85043376092&partnerID=8YFLogxK
U2 - 10.3389/fpls.2018.00258
DO - 10.3389/fpls.2018.00258
M3 - Article
AN - SCOPUS:85043376092
SN - 1664-462X
VL - 9
JO - Frontiers in Plant Science
JF - Frontiers in Plant Science
M1 - 258
ER -