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bioRxiv · 10.1101/2023.03.02.530895

ERF1 inhibits lateral root emergence by promoting local auxin accumulation with altered distribution and repressing ARF7 expression

Abstract

Lateral roots (LRs) are crucial for plants to sense environmental signals in addition to water and nutrient absorption. Auxin is key for LR formation, but the underlying mechanisms are not fully understood. Here we report that Arabidopsis ERF1 inhibits LR emergence by promoting local auxin accumulation with altered distribution and regulating auxin signaling. Loss of ERF1 increases LR density compared with the wild type, whereas ERF1 overexpression causes the opposite phenotype. ERF1 enhances auxin transport by upregulating PIN1 and AUX1, resulting in excessive auxin accumulation in the endodermal, cortical, and epidermal cells surrounding LR primordia. Furthermore, ERF1 represses ARF7 transcription, consequently affecting the expression of cell wall remodeling genes that facilitate LR emergence. Together, our study reveals that ERF1 integrates environmental signals to promote local auxin accumulation with altered distribution and repress ARF7, consequently inhibiting LR emergence in adaptation to fluctuating environments. HighlightsO_LIERF1 functions as a negative regulator of lateral root emergence C_LIO_LIERF1 enhances rootward and shootward auxin transport by directly upregulating the expression of PIN1 and AUX1, resulting in high local auxin accumulation and abnormal auxin distribution in the endodermal, cortical, and epidermal cells overlying lateral root primordia C_LIO_LIERF1 represses the transcription of ARF7 and cell wall remodeling genes in lateral root emergence C_LI

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Zhao, P.-X., Xiang, C.. 2023-03-03. ERF1 inhibits lateral root emergence by promoting local auxin accumulation with altered distribution and repressing ARF7 expression. https://doi.org/10.1101/2023.03.02.530895

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