• Researchers Reveal a Mechanism Involving Two Partners in a Complex to Regulate Genes for Salt Tolerance

    TIME: 19 Sep 2017
    Prof. CHEN Shouyi’s group and Prof. ZHANG Jinsong’s group, both from the Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, recently identified a special PHD-finger protein, GmPHD6, from soybean.
     
    GmPHD6 belongs to the Alfin subfamily of PHD-finger proteins. Unlike the other members repressing transcription, GmPHD6 does not possess any transcriptional regulatory ability.
     
    The researchers found that GmPHD6 could bind to LHP1 (like heterochromatin protein 1). Relying on the activating ability of LHP1, GmPHD6 regulates expression of downstream genes and confers salt tolerance in soybean plants with transgenic hairy roots.
     
    PHD fingers are histone code readers. GmPHD6 could ‘read’ H3K4me0/1/2 through its N-terminal domain but not the PHD domain, which is different from other PHD finger proteins. The N-terminal domain also recognizes promoter regions of GmPHD6’s downstream genes, whereas the PHD domain is responsible for the interaction with LHP1.
     
    A working model of GmPHD6 is built according to the above findings. H3K4me0/1/2 may be related to stress response in plants and they could recruit GmPHD6. GmPHD6 recruits its coactivator, LHP1, to form a transcriptional regulation complex in which GmPHD6 targets gene promoters, whereas LHP1 activates their expression under salt stress in soybean.
     
    This study is a valuable supplement for the mechanisms of AL/PHD-finger proteins, which also provides important information to help improve stress tolerance in plants.
     
    This work entitled “A histone code reader and a transcriptional activator interact to regulate genes for salt tolerance” was published online on Sep 5th, 2017, in Plant Physiology (doi: 10.1104/pp.16.01764.). Dr. WEI Wei is the first author of this paper.
     
    The study was supported by the National Key Research and Development Program of China, the 973 Project, the Transgenic Research Project, the National Natural Science Foundation of China and the State Key Lab of Plant Genomics.
     
     
     
    A model of the GmPHD6/LHP1 complex recognizing histone code and mediating expression of downstream genes (Image by IGDB)
     
     
    Contact:
    Dr. ZHANG Jinsong