TY - JOUR
T1 - Melatonin regulates root meristem by repressing auxin synthesis and polar auxin transport in arabidopsis
AU - Wang, Qiannan
AU - An, Bang
AU - Wei, Yunxie
AU - Reiter, Russel J.
AU - Shi, Haitao
AU - Luo, Hongli
AU - He, Chaozu
N1 - Funding Information:
This work was supported by the Hainan Natural Science Foundation (No. 20163052), the startup funding and the scientific research foundation of Hainan University (No. kyqd1516, No. kyqd1531), and the National Natural Science Foundation of China (No. 31570249). We thank ABRC and many researchers for sharing their published materials.
PY - 2016/12/15
Y1 - 2016/12/15
N2 - Melatonin (N-acetyl-5-methoxytryptamine) plays important roles in regulating both biotic and abiotic stress tolerance, biological rhythms, plant growth and development. Sharing the same substrate (tryptophan) for the biosynthesis, melatonin and auxin also have similar effects in plant development. However, the specific function of melatonin in modulating plant root growth and the relationship between melatonin and auxin as well as underlying mechanisms are still unclear. In this study, we found high concentration of melatonin remarkably inhibited root growth in Arabidopsis by reducing root meristem size. Further studies showed that melatonin negatively regulated auxin biosynthesis, the expression of PINFORMED (PIN) proteins as well as auxin response in Arabidopsis. Moreover, the root growth of the triple mutant pin1pin3pin7 was more tolerant than that of wild-type in response to melatonin treatment, suggesting the essential role of PIN1/3/7 in melatonin-mediated root growth. Combination treatment of melatonin and 5-Triiodobenzoic acid (TIBA) did not enhance melatonin-mediated reduction of root meristem size, indicating that polar auxin transport (PAT) may be necessary for the regulation of root meristem size by melatonin treatment. Taken together, this study indicates that melatonin regulates root growth in Arabidopsis, through auxin synthesis and polar auxin transport, at least partially.
AB - Melatonin (N-acetyl-5-methoxytryptamine) plays important roles in regulating both biotic and abiotic stress tolerance, biological rhythms, plant growth and development. Sharing the same substrate (tryptophan) for the biosynthesis, melatonin and auxin also have similar effects in plant development. However, the specific function of melatonin in modulating plant root growth and the relationship between melatonin and auxin as well as underlying mechanisms are still unclear. In this study, we found high concentration of melatonin remarkably inhibited root growth in Arabidopsis by reducing root meristem size. Further studies showed that melatonin negatively regulated auxin biosynthesis, the expression of PINFORMED (PIN) proteins as well as auxin response in Arabidopsis. Moreover, the root growth of the triple mutant pin1pin3pin7 was more tolerant than that of wild-type in response to melatonin treatment, suggesting the essential role of PIN1/3/7 in melatonin-mediated root growth. Combination treatment of melatonin and 5-Triiodobenzoic acid (TIBA) did not enhance melatonin-mediated reduction of root meristem size, indicating that polar auxin transport (PAT) may be necessary for the regulation of root meristem size by melatonin treatment. Taken together, this study indicates that melatonin regulates root growth in Arabidopsis, through auxin synthesis and polar auxin transport, at least partially.
KW - Arabidopsis
KW - Auxin
KW - Auxin synthesis
KW - Melatonin
KW - Polar auxin transport
KW - Root meristem
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UR - http://www.scopus.com/inward/citedby.url?scp=85007321868&partnerID=8YFLogxK
U2 - 10.3389/fpls.2016.01882
DO - 10.3389/fpls.2016.01882
M3 - Article
AN - SCOPUS:85007321868
VL - 7
JO - Frontiers in Plant Science
JF - Frontiers in Plant Science
SN - 1664-462X
IS - DECEMBER2016
M1 - 1882
ER -