Title: Rational design and testing of abiotic stress‐inducible synthetic promoters from poplar cis ‐regulatory elements

Abstract

Abiotic stress resistance traits may be especially crucial for sustainable production of bioenergy tree crops. Here, we show the performance of a set of rationally designed osmotic-related and salt stress-inducible synthetic promoters for use in hybrid poplar. De novo motif-detecting algorithms yielded 30 water-deficit (SD) and 34 salt stress (SS) candidate DNA motifs from relevant poplar transcriptomes. We selected three conserved water-deficit stress motifs (SD18, SD13 and SD9) found in 16 co-expressed gene promoters, and we discovered a well-conserved motif for salt response (SS16). We characterized several native poplar stress-inducible promoters to enable comparisons with our synthetic promoters. Fifteen synthetic promoters were designed using various SD and SS subdomains, in which heptameric repeats of five-to-eight subdomain bases were fused to a common core promoter downstream, which, in turn, drove a green fluorescent protein (GFP) gene for reporter assays. These 15 synthetic promoters were screened by transient expression assays in poplar leaf mesophyll protoplasts and agroinfiltrated Nicotiana benthamiana leaves under osmotic stress conditions. Twelve synthetic promoters were induced in transient expression assays with a GFP readout. Of these, five promoters (SD18-1, SD9-2, SS16-1, SS16-2 and SS16-3) endowed higher inducibility under osmotic stress conditions than native promoters. These five synthetic promoters weremore » stably transformed into Arabidopsis thaliana to study inducibility in whole plants. Herein, SD18-1 and SD9-2 were induced by water-deficit stress, whereas SS16-1, SS16-2 and SS16-3 were induced by salt stress. The synthetic biology design pipeline resulted in five synthetic promoters that outperformed endogenous promoters in transgenic plants.« less

Authors:

Yang, Yongil  ^[1];

• Search DOE PAGES for author "Yang, Yongil"
• Search DOE PAGES for ORCID "0000-0002-6925-5410"

Lee, Jun Hyung  ^[2];

• Search DOE PAGES for author "Lee, Jun Hyung"
• Search DOE PAGES for ORCID "0000-0002-7137-7169"

Poindexter, Magen R. ^[1]; Shao, Yuanhua ^[1]; Liu, Wusheng  ^[3];

• Search DOE PAGES for author "Liu, Wusheng"
• Search DOE PAGES for ORCID "0000-0001-9256-4310"

Lenaghan, Scott C. ^[4]; Ahkami, Amir H. ^[5]; Blumwald, Eduardo ^[6]; Stewart, Jr, Charles Neal  ^[1]

• Search DOE PAGES for author "Stewart, Jr, Charles Neal"
• Search DOE PAGES for ORCID "0000-0003-3026-9193"

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+ Show Author Affiliations

1. Center for Agricultural Synthetic Biology University of Tennessee Institute of Agriculture Knoxville TN USA, Department of Plant Sciences University of Tennessee Knoxville TN USA
2. Center for Agricultural Synthetic Biology University of Tennessee Institute of Agriculture Knoxville TN USA, Department of Plant Sciences University of Tennessee Knoxville TN USA, Biosciences Division Oak Ridge National Laboratory Oak Ridge TN USA
3. Department of Plant Sciences University of Tennessee Knoxville TN USA, Department of Horticultural Science North Carolina State University Raleigh NC USA
4. Center for Agricultural Synthetic Biology University of Tennessee Institute of Agriculture Knoxville TN USA, Department of Food Science University of Tennessee Knoxville TN USA
5. Environmental Molecular Sciences Laboratory (EMSL) Pacific Northwest National Laboratory (PNNL) Richland WA USA
6. Department of Plant Sciences University of California Davis CA USA

Publication Date:

Mon Feb 08 00:00:00 EST 2021

Research Org.:

Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States); Pacific Northwest National Laboratory (PNNL), Richland, WA (United States)

Sponsoring Org.:

USDOE; USDOE Office of Science (SC), Biological and Environmental Research (BER). Earth and Environmental Systems Science Division

OSTI Identifier:

1765044

Alternate Identifier(s):

OSTI ID: 1787091; OSTI ID: 1787965; OSTI ID: 1814270; OSTI ID: 1842822

Report Number(s):

PNNL-SA-160913
Journal ID: ISSN 1467-7644

Grant/Contract Number:  

DE‐SC0018347; AC05-00OR22725; SC0018347; AC05-76RL01830

Resource Type:

Published Article

Journal Name:

Plant Biotechnology Journal

Additional Journal Information:

Journal Name: Plant Biotechnology Journal Journal Volume: 19 Journal Issue: 7; Journal ID: ISSN 1467-7644

Publisher:

Wiley-Blackwell

Country of Publication:

United Kingdom

Language:

English

Subject:

59 BASIC BIOLOGICAL SCIENCES; 09 BIOMASS FUELS; synthetic biology; synthetic promoters; de novo motif analysis; computational design; abiotic stress; cis-regulatory elements; poplar; bioenergy