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Soil salinity is one of the major threats to agricultural productivity worldwide. Salt stress exposure alters root and shoots growth rates, thereby affecting overall plant performance. While past studies have extensively documented the effect of salt stress on root elongation and shoot development separately, here we take an innovative approach by examining the coordination of root and shoot growth under salt stress conditions. Utilizing a newly developed tool for quantifying the root:shoot ratio in agar-grownArabidopsisseedlings, we found that salt stress results in a loss of coordination between root and shoot growth rates. We identify a specific gene cluster encoding domain-of-unknown-function 247 (DUF247), and characterize one of these genes asSaltRoot:shootRatioRegulatorGene (SR3G). Further analysis elucidates the role of SR3G as a negative regulator of salt stress tolerance, revealing its function in regulating shoot growth, root suberization, and sodium accumulation. We further characterize thatSR3Gexpression is modulated byWRKY75transcription factor, known as a positive regulator of salt stress tolerance. Finally, we show that the salt stress sensitivity ofwrky75mutant is completely diminished when it is combined withsr3gmutation. Together, our results demonstrate that utilizing root:shoot ratio as an architectural feature leads to the discovery of a new stress resilience gene. The study’s innovative approach and findings not only contribute to our understanding of plant stress tolerance mechanisms but also open new avenues for genetic and agronomic strategies to enhance crop environmental resilience.
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This content will become publicly available on December 1, 2025
The long noncoding RNA LAL contributes to salinity tolerance by modulating LHCB1s’ expression in Medicago truncatula
Abstract Long non-coding RNAs (lncRNAs) are abundant in plants, however, their regulatory roles remain unclear in most biological processes, such as response in salinity stress which is harm to plant production. Here we show a lncRNA inMedicago truncatulaidentified from salt-treated Medicagotruncatulais important for salinity tolerance. We name the lncRNALAL,LncRNAANTISENSEtoM. truncatulaLIGHT-HARVESTING CHLOROPHYLL A/B BINDING(MtLHCB)genes. LALis an antisense to four consecutiveMtLHCBgenes on chromosome 6. In salt-treatedM. truncatula,LALis suppressed in an early stage but induced later; this pattern is opposite to that of the fourMtLHCBs. Thelalmutants show enhanced salinity tolerance, while overexpressingLALdisrupts this superior tolerance in thelalbackground, which indicates its regulatory role in salinity response. The regulatory role ofLALonMtLHCB1.4is further verified by transient co-expression ofLALandMtLHCB1.4-GFPin tobacco leaves, in which the cleavage ofMtLHCB1.4and production of secondary interfering RNA is identified. This work demonstrates a lncRNA,LAL, functioning as a regulator that fine-tunes salinity tolerance via regulatingMtLHCB1s’ expression inM. truncatula.
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- Award ID(s):
- 2233714
- PAR ID:
- 10507216
- Publisher / Repository:
- Nature
- Date Published:
- Journal Name:
- Communications Biology
- Volume:
- 7
- Issue:
- 1
- ISSN:
- 2399-3642
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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