AtMYB44 Positively Regulates the Enhanced Elongation of Primary Roots Induced by N-3-Oxo-Hexanoyl-Homoserine Lactone in Arabidopsis thaliana.
N-acyl-homoserine lactones (AHL) are the quorum-sensing (QS) signal molecules used by many gram-negative bacteria to coordinate their collective behavior in a population. Recent evidence demonstrates their roles in plant root growth and defense responses. AtMYB44 is a multifaceted transcriptional factor that functions in many physiological processes in plants but whether AtMYB44 modulates the plant response to AHL with aspects of primary root elongation remains unknown. Here, we show that the expression of AtMYB44 was upregulated upon treatment with N-3-oxo-hexanoyl-homoserine lactone (3OC6-HSL). The stimulatory effect of 3OC6-HSL on primary root elongation was abolished in the AtMYB44 functional-deficiency mutant atmby44. In contrast, an enhanced promoting-impact of 3OC6-HSL on primary root growth was observed in AtMYB44-overexpressing plant MYB44OTA. Cellular analysis indicated that the prolonged primary root elicited by 3OC6-HSL is the consequence of increased cell division in the meristem zone and enhanced cell elongation in the elongation zone, and AtMYB44 may act as a positive regulator in this process. Furthermore, we demonstrated that AtMYB44 might participate in the 3OC6-HSL-mediated primary root growth via regulating the expression of cytokinin- and auxin-related genes. The data establish a genetic connection between the regulatory role of AtMYB44 in phytohormones-related gene expression and plant response to the bacterial QS signal.
1 Biology Institute, Hebei Academy of Sciences; and.|2 Hebei Engineering and Technology Center of Microbiological Control on Main Crop Disease, 46th South Street of Friendship, Shijiazhuang, 050051, China.
Qian
Q
Zhao
1 Biology Institute, Hebei Academy of Sciences; and.
Man
M
Li
1 Biology Institute, Hebei Academy of Sciences; and.|2 Hebei Engineering and Technology Center of Microbiological Control on Main Crop Disease, 46th South Street of Friendship, Shijiazhuang, 050051, China.
Zhenhua
Z
Jia
1 Biology Institute, Hebei Academy of Sciences; and.|2 Hebei Engineering and Technology Center of Microbiological Control on Main Crop Disease, 46th South Street of Friendship, Shijiazhuang, 050051, China.
Fang
F
Liu
1 Biology Institute, Hebei Academy of Sciences; and.|2 Hebei Engineering and Technology Center of Microbiological Control on Main Crop Disease, 46th South Street of Friendship, Shijiazhuang, 050051, China.
Hong
H
Ma
1 Biology Institute, Hebei Academy of Sciences; and.|2 Hebei Engineering and Technology Center of Microbiological Control on Main Crop Disease, 46th South Street of Friendship, Shijiazhuang, 050051, China.
Yali
Y
Huang
1 Biology Institute, Hebei Academy of Sciences; and.|2 Hebei Engineering and Technology Center of Microbiological Control on Main Crop Disease, 46th South Street of Friendship, Shijiazhuang, 050051, China.
Shuishan
S
Song
D054742:Acyl-Butyrolactones / Q000494:pharmacology*; D017360:Arabidopsis / Q000235:genetics* / Q000254:growth & development; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism*; D003583:Cytokinins / Q000494:pharmacology; D007210:Indoleacetic Acids / Q000494:pharmacology*; D009154:Mutation; D020411:Oligonucleotide Array Sequence Analysis; D010937:Plant Growth Regulators / Q000494:pharmacology*; D018517:Plant Roots / Q000235:genetics / Q000254:growth & development; D053038:Quorum Sensing; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism*
D054742:Acyl-Butyrolactones; D029681:Arabidopsis Proteins; D003583:Cytokinins; D007210:Indoleacetic Acids; C529221:At5g67300 protein, Arabidopsis; D010937:Plant Growth Regulators; D014157:Transcription Factors