Open AccessR2R3 MYB‐dependent auxin signalling regulates trichome formation, and increased trichome density confers spider mite tolerance on tomato
Author(s) -
Yuan Yujin,
Xu Xin,
Luo Yingqing,
Gong Zehao,
Hu Xiaowei,
Wu Mengbo,
Liu Yudong,
Yan Fang,
Zhang Xiaolan,
Zhang Wenfa,
Tang Yuwei,
Feng Bihong,
Li Zhengguo,
Jiang CaiZhong,
Deng Wei
Publication year - 2021
Publication title -
plant biotechnology journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 3.525
H-Index - 115
eISSN - 1467-7652
pISSN - 1467-7644
DOI - 10.1111/pbi.13448
Subject(s) - trichome , biology , botany , auxin , myb , spider mite , microbiology and biotechnology , gene , transcription factor , biochemistry , mite
Summary Unicellular and multicellular tomato trichomes function as mechanical and chemical barriers against herbivores. Auxin treatment increased the formation of II, V and VI type trichomes in tomato leaves. The auxin response factor gene SlARF4 , which was highly expressed in II, V and VI type trichomes, positively regulated the auxin‐induced formation of II, V and VI type trichomes in the tomato leaves. SlARF4 overexpression plants with high densities of these trichomes exhibited tolerance to spider mites. Two R2R3 MYB genes, SlTHM1 and SlMYB52, were directly targeted and inhibited by SlARF4. SlTHM1 was specifically expressed in II and VI type trichomes and negatively regulated the auxin‐induced formation of II and VI type trichomes in the tomato leaves. SlTHM1 down‐regulation plants with high densities of II and VI type trichomes also showed tolerance to spider mites. SlMYB52 was specifically expressed in V type trichomes and negatively regulated the auxin‐induced formation of V type trichome in the tomato leaves. The regulation of SlARF4 on the formation of II, V and VI type trichomes depended on SlTHM1 and SlMYB52, which directly targeted cyclin gene SlCycB2 and increased its expression. In conclusion, our data indicates that the R2R3 MYB‐dependent auxin signalling pathway regulates the formation of II, V and VI type trichomes in tomato leaves. Our study provides an effective method for improving the tolerance of tomato to spider mites.