In a new study published in Nature Communications on April 26, researchers led by XIAO Jun from the Institute of Genetics and Developmental Biology of the Chinese Academy of Sciences, in collaboration with YU Xiang's group at Shanghai Jiao Tong University, have uncovered a novel mechanism by which the plant hormone abscisic acid (ABA) regulates mRNA translation through the RNA-binding protein GRP7.

Using an integrative approach that combined transcriptomics, translatomics, molecular biology, biochemistry, and genetics, the researchers demonstrated that ABA signaling components—including RCAR/PYR/PYLs receptors, PP2Cs, and SnRK2 kinases—also influence translation efficiency. Immunoprecipitation-mass spectrometry (IP-MS) analysis identified Glycine-rich RNA-binding protein 7 (GRP7) as a ribosome-associated protein responsive to ABA. GRP7 and its homolog GRP8, which share high sequence similarity and functional redundancy, were further studied using a CRISPR/Cas9-engineered double mutant (grp7grp8).

The researchers also found that ABA activates AREB/ABFs through SnRK2s for transcriptional regulation while inhibiting GRP7&8-mediated translation regulation. By creating a quintuple mutant combining grp7grp8 with snrk2.2/2.3/2.6 through hybridization, genetic phenotyping revealed that under low ABA concentrations, the transcriptional regulation mediated by AREB/ABFs dominates, whereas under high ABA concentrations, the translation regulation mediated by GRP7&8 becomes more significant.

It is worth noting that the detailed experimental methods, analysis methods, and quality control of data resources for the Ribo-seq and CLIP-seq experiments of Col-0 and grp7grp8 under ABA treatment were published in Scientific Data on December 28, 2024.