Related Experiment Video
Updated: Aug 7, 2025

Measuring Gene Expression in Bombarded Barley Aleurone Layers with Increased Throughput
Published on: March 30, 2018
BBX30/miP1b and BBX31/miP1a form a positive feedback loop with ABI5 to regulate ABA-mediated postgermination seedling
1Department of Biological Sciences, Indian Institute of Science Education and Research Bhopal, Bhopal, 462066, Madhya Pradesh, India.
Abstract:
In plants, the switch to autotrophic growth involves germination followed by postgermination seedling establishment. When environmental conditions are not favorable, the stress hormone abscisic acid (ABA) signals plants to postpone seedling establishment by inducing the expression of the transcription factor ABI5. The levels of ABI5 determine the efficiency of the ABA-mediated postgermination developmental growth arrest. The molecular mechanisms regulating the stability and activity of ABI5 during the transition to light are less known. Using genetic, molecular, and biochemical approach, we found that two B-box domain containing proteins BBX31 and BBX30 alongwith ABI5 inhibit postgermination seedling establishment in a partially interdependent manner. BBX31 and BBX30 are also characterized as microProteins miP1a and miP1b, respectively, based on their small size, single domain, and ability to interact with multidomain proteins. miP1a/BBX31 and miP1b/BBX30 physically interact with ABI5 to stabilize it and promote its binding to promoters of downstream genes. ABI5 reciprocally induces the expression of BBX30 and BBX31 by directly binding to their promoter. ABI5 and the two microProteins thereby form a positive feedback loop to promote ABA-mediated developmental arrest of seedlings.
More Related Videos
08:52A Seed Coat Bedding Assay to Genetically Explore In Vitro How the Endosperm Controls Seed Germination in Arabidopsis thaliana
Published on: November 9, 2013
08:54Imaging Spatial Reorganization of a MAPK Signaling Pathway Using the Tobacco Transient Expression System
Published on: March 20, 2016
Related Concept Videos
Cell Signaling in Plants
Hedgehog Signaling Pathway
The Spindle Assembly Checkpoint
Many proteins function together to control the spindle assembly checkpoint. Mutations affecting these proteins may allow cells to proceed into anaphase prematurely, resulting in the...
TGF - β Signaling Pathway
Receptor Downregulation in MVBs
The EGFR can initiate signaling pathways that lead to cell proliferation, migration, and differentiation. Overexpression of EGFR stimulates cells to proliferate. Excessive EGFR...