Title: mRNA Transcript Abundance during Plant Growth and the Influence of Li⁺ Exposure

Abstract

Lithium (Li) toxicity in plants is, at a minimum, a function of Li⁺ concentration, exposure time, species and growth conditions. Most plant studies with Li⁺ focus on short-term acute exposures. This study examines short- and long-term effects of Li⁺ exposure in Arabidopsis with Li⁺ uptake studies and measured shoot mRNA transcript abundance levels in treated and control plants. Stress, pathogen-response and arabinogalactan protein genes were typically more up-regulated in older (chronic, low level) Li⁺-treatment plants and in the much younger plants from acute high-level exposures. The gene regulation behavior of high-level Li⁺ resembled prior studies due to its influence on: inositol synthesis, 1-aminocyclopropane-1-carboxylate synthases and membrane ion transport. In contrast, chronically-exposed plants had gene regulation responses that were indicative of pathogen, cold, and heavy-metal stress, cell wall degradation, ethylene production, signal transduction, and calcium-release modulation. Acute Li⁺ exposure phenocopies magnesium-deficiency symptoms and is associated with elevated expression of stress response genes that could lead to consumption of metabolic and transcriptional energy reserves and the dedication of more resources to cell development. In contrast, chronic Li⁺ exposure increases expression signal transduction genes. The identification of new Li⁺-sensitive genes and a gene-based “response plan” for acute and chronic Li⁺ exposure are delineated.

Authors:

Duff, M. C. ^[1]; Kuhne, W. W. ^[1]; Halverson, N. V. ^[1]; Chang, C. -S. ^[2]; Kitamura, E. ^[2]; Hawthorn, L. ^[2]; Martinez, N. E. ^[3]; Stafford, C. ^[4]; Milliken, C. E. ^[1]; Caldwell, E. F. ^[1]; Stieve-Caldwell, E. ^[1]

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+ Show Author Affiliations

1. Savannah River National Laboratory, Aiken, SC (United States)
2. Georgia Regents University Cancer Center, Augusta, GA (United States). Integrated Genomics Core
3. Savannah River National Laboratory, Aiken, SC (United States); Colorado State University, Ft. Collins, CO (United States). Dept. of Environmental and Radiological Health Sciences
4. Savannah River National Laboratory, Aiken, SC (United States); Univ. of South Carolina Medical School, Columbia, SC (United States)

Publication Date:

Thu Oct 23 00:00:00 EDT 2014

Research Org.:

Savannah River Site (SRS), Aiken, SC (United States)

Sponsoring Org.:

USDOE Office of Environmental Management (EM); USDOE National Nuclear Security Administration (NNSA), Office of Defense Nuclear Nonproliferation

OSTI Identifier:

1171509

Alternate Identifier(s):

OSTI ID: 1556340

Report Number(s):

SRNL-STI-2014-00522
Journal ID: ISSN 0168-9452

Grant/Contract Number:  

AC09-08SR22470; FG52-05NA27035

Resource Type:

Accepted Manuscript

Journal Name:

Plant Science

Additional Journal Information:

Journal Volume: 229; Journal ID: ISSN 0168-9452

Publisher:

Elsevier

Country of Publication:

United States

Language:

English

Subject:

38 RADIATION CHEMISTRY, RADIOCHEMISTRY, AND NUCLEAR CHEMISTRY; Arabidopsis thaliana; Microarray; Next generation sequencing; Lithium exposure; Hydroponics; Soil