The RNA Polymerase-Associated Factor 1 Complex Is Required for Plant Touch Responses

Area of Science:

• Plant Biology
• Molecular Biology
• Genetics

Background:

• Thigmomorphogenesis is a plant's altered development in response to touch.
• Understanding how plants sense and record mechanical stimuli is crucial for plant science.

Purpose of the Study:

• To identify genes involved in sensing and recording multiple touch stimuli.
• To investigate the role of the RNA polymerase II-associated factor 1 (Paf1) complex in thigmomorphogenesis.

Main Methods:

• Forward genetic screen to identify touch-insensitive mutants.
• Characterization of the touch insensitive (ths1) mutant, an allele of VERNALIZATION INDEPENDENCE 3 (VIP3).
• Analysis of histone modification and gene expression in response to touch.

Main Results:

• The ths1 mutant, a VIP3 allele, shows defects in shoot and root thigmomorphogenesis.
• VIP3 is part of the conserved Paf1 complex, involved in histone modification and RNA processing.
• VIP3 regulates histone H3K36 trimethylation and touch-induced expression of TOUCH3 and TOUCH4 genes.

Conclusions:

• The evolutionarily conserved Paf1 complex, through VIP3, is essential for plant responses to mechanical stimulation.
• VIP3 mediates both short- and long-term responses to touch by influencing chromatin modification.
• This study provides insights into the molecular mechanisms plants use to record mechanical signals for thigmomorphogenesis.