The TaDof-2D-miR1832-TaP450-7A module regulates low-temperature-induced seed dormancy release in wheat.

Area of Science:

• Plant Biology
• Molecular Genetics
• Agricultural Science

Background:

• Low temperatures (LT) during wheat seed development release dormancy, but the regulatory mechanisms are not fully understood.
• Seed dormancy (SD) is a critical trait influencing crop establishment and yield.

Purpose of the Study:

• To elucidate the molecular mechanism of LT-induced dormancy release in wheat.
• To identify key genetic regulators involved in wheat seed dormancy.

Main Methods:

• Whole-transcriptome sequencing to identify novel microRNAs.
• Germination experiments, gene silencing, and overexpression studies.
• Molecular assays including yeast one-hybrid, EMSA, dual-luciferase, and 5'-RACE.

Main Results:

• A novel microRNA, miR1832, was identified and found to be downregulated by LT.
• miR1832 positively regulates seed dormancy (SD), while its silencing reduces SD.
• The TaDof-2D transcription factor directly binds to the miR1832 promoter, inhibiting its transcription.
• miR1832 targets the TaP450-7A gene, which negatively regulates SD.
• The TaDof-2D-miR1832-TaP450-7A module influences ABA, GA pathways, and α-amylase activity.

Conclusions:

• A novel regulatory pathway (TaDof-2D-miR1832-TaP450-7A) for LT-induced dormancy release in wheat was discovered.
• This pathway provides insights into the genetic control of seed dormancy.
• Findings offer potential genetic resources and molecular markers for breeding wheat with improved dormancy characteristics.