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Hydrogen peroxide homeostasis provides beneficial micro‐environment for SHR‐mediated periclinal division in Arabidopsis root
Author(s) -
Li Pengxue,
Cai Qiang,
Wang Hong,
Li Shuang,
Cheng Jie,
Li Haiyang,
Yu Qiaozhi,
Wu Shuang
Publication year - 2020
Publication title -
new phytologist
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 3.742
H-Index - 244
eISSN - 1469-8137
pISSN - 0028-646X
DOI - 10.1111/nph.16824
Subject(s) - endodermis , arabidopsis , reactive oxygen species , microbiology and biotechnology , cell division , superoxide , biology , arabidopsis thaliana , hydrogen peroxide , botany , chemistry , biochemistry , cell , mutant , gene , enzyme
Summary The precise regulation of asymmetric cell division (ACD) is essential for plant organogenesis. In Arabidopsis roots, SHORT‐ROOT (SHR) functions to promote periclinal division in cortex/endodermis initials, which generate the ground tissue patterning. Although multiple downstream transcription factors and interplaying hormone pathways have been reported, the cellular mechanism that affects SHR‐mediated periclinal division remains largely unclear. Here, we found that SHR can substantially elevate reactive oxygen species (ROS) levels in Arabidopsis roots by activating respiratory burst oxidase homologs (RBOHs). Among the ROS products, hydrogen peroxide (H 2 O 2 ) rather than superoxide (O 2 − ) was shown to play a critical role in SHR‐mediated periclinal division. Scavenging H 2 O 2 could markedly impair the ability of SHR to induce periclinal division. We also show that salicylic acid (SA) can promote H 2 O 2 production by repressing CAT expression, which greatly increased periclinal division in root endodermis. As a result, middle cortex was more frequently formed in the endodermis of snc1 , a mutant with accumulated endogenous SA and H 2 O 2 . In addition to RBOHs, SHR also activated the SA pathway, which might contribute to the elevated H 2 O 2 level induced by SHR. Thus, our data suggest a mechanism by which SHR creates the optimal micro‐environment for periclinal division by maintaining ROS homeostasis in Arabidopsis roots.