Abstract
The mechanisms controlling the transcription of gene sets in specific regions of a plant embryo shortly after fertilization remain unknown. Previously, we showed that G564 mRNA, encoding a protein of unknown function, accumulates to high levels in the giant suspensor of both Scarlet Runner Bean (SRB) and Common Bean embryos, and a cis-regulatory module containing three unique DNA sequences, designated as the 10-bp, Region 2, and Fifth motifs, is required for G564 suspensor-specific transcription [Henry KF, et al. (2015) Plant Mol Biol 88:207–217; Kawashima T, et al. (2009) Proc Natl Acad Sci USA 106:3627–3632]. We tested the hypothesis that these motifs are also required for transcription of the SRB GA 20-oxidase gene, which encodes a gibberellic acid hormone biosynthesis enzyme and is coexpressed with G564 at a high level in giant bean suspensors. We used deletion and gain-of-function experiments in transgenic tobacco embryos to show that two GA 20-oxidase DNA regions are required for suspensor-specific transcription, one in the 5′ UTR (+119 to +205) and another in the 5′ upstream region (−341 to −316). Mutagenesis of sequences in these two regions determined that the cis-regulatory motifs required for G564 suspensor transcription are also required for GA 20-oxidase transcription within the suspensor, although the motif arrangement differs. Our results demonstrate the flexibility of motif positioning within a cis-regulatory module that activates gene transcription within giant bean suspensors and suggest that G564 and GA 20-oxidase comprise part of a suspensor gene regulatory network.
Document Type
Article
Publication Date
6-19-2018
Digital Object Identifier (DOI)
https://doi.org/10.1073/pnas.1805802115
Funding Information
This work was funded by a grant from the National Science Foundation Plant Genome Program.
Related Content
This article contains supporting information online at www.pnas.org/lookup/suppl/doi:10.1073/pnas.1805802115/-/DCSupplemental.
Repository Citation
Henry, Kelli F.; Bui, Anhthu Q.; Kawashima, Tomokazu; and Goldberg, Robert B., "A Shared Cis-Regulatory Module Activates Transcription in the Suspensor of Plant Embryos" (2018). Plant and Soil Sciences Faculty Publications. 100.
https://uknowledge.uky.edu/pss_facpub/100
Supporting Information
Notes/Citation Information
Published in PNAS, v. 115, no. 25, E5824-E5833.
Copyright © 2018 the Author(s). Published by PNAS.
This open access article is distributed under Creative Commons Attribution-NonCommercial-NoDerivatives License 4.0 (CC BY-NC-ND).