The Arabidopsis RING-Type E3 Ligase TEAR1 Controls Leaf Development by Targeting the TIE1 Transcriptional Repressor for Degradation

Abstract

The developmental plasticity of leaf size and shape is important for leaf function and plant survival. However, the mechanisms by which plants form diverse leaves in response to environmental conditions are not well understood. Here, we identified TIE1-ASSOCIATED RING-TYPE E3 LIGASE1 (TEAR1) and found that it regulates leaf development by promoting the degradation of TCP INTERACTOR-CONTAINING EAR MOTIF PROTEIN1 (TIE1), an important repressor of CINCINNATA (CIN)-like TEOSINTE BRANCHED1/CYCLOIDEA/PCF (TCP) transcription factors, which are key for leaf development. TEAR1 contains a typical C3H2C3-type RING domain and has E3 ligase activity. We show that TEAR1 interacts with the TCP repressor TIE1, which is ubiquitinated in vivo and degraded by the 26S proteasome system. We demonstrate that TEAR1 is colocalized with TIE1 in nuclei and negatively regulates TIE1 protein levels. Overexpression of TEAR1 rescued leaf defects caused by TIE1 overexpression, whereas disruption of TEAR1 resulted in leaf phenotypes resembling those caused by TIE1 overexpression or TCP dysfunction. Deficiency in TEAR partially rescued the leaf defects of TCP4 overexpression line and enhanced the wavy leaf phenotypes of jaw-5D. We propose that TEAR1 positively regulates CIN-like TCP activity to promote leaf development by mediating the degradation of the TCP repressor TIE1.

The TIE1 transcriptional repressor controls shoot branching by directly repressing BRANCHED1 in Arabidopsis

“…However, tie1-D and jaw-D , in both of which the TCP activity was downregulated, did not display completely identical phenotypes, which indicates that TIE1 may also bind other transcription factors and regulate additional biological processes. In addition, TIE1 is regulated by E3-ligase proteins termed TIE1-associated RING-type E3 ligases (TEARs) [ 26 ]. TEARs interact with TIE1 and are responsible for TIE1 degradation, which boosts CIN-like TCP activity during leaf development.…”

The Arabidopsis USL1 controls multiple aspects of development by affecting late endosome morphology

“…In order to test the interaction of AtVPS30 and USL1 using the firefly luciferase complementation imaging assay, the pCAMBIA‐USL1‐nLUC was generated by an LR reaction between pCAMBIA‐nLUC (Chen et al ., ; Zhang et al ., ) and pENTRY‐USL1nsc. The pCAMBIA‐cLUC‐VPS30 was generated by an LR reaction between pCAMBIA‐cLUC (Zhang et al ., ) and pENTRY‐VPS30nsc.…”

Dissecting the genetic architecture of seed-cotton and lint yields in Upland cotton using genome-wide association mapping

“…The two genes, Gh_D05G1077 and Gh_D13G1571, presented high expression levels in all of the tissues, except the torus. As mentioned above, the homologous gene of Gh_D05G1077 plays a critical role in pollen tube-pistil signaling, fertilization, and seed production (Hafidh et al 2016), and the homologous gene of Gh_D13G1571 plays an important role in leaf development by mediating the degradation of the TCP repressor TIE1 (Zhang et al 2017). Thus, these two genes may contribute to the biological production of cotton, and thus also contribute to SY.…”

“…of photomorphogenesis, to affect anthocyanin accumulation and chloroplast biogenesis, and to regulate light-dependent development in Arabidopsis (Chang et al 2008, Datta et al 2008. Gh_D13G1571 is homologous to AT1G53190 (TEAR1), which positively regulates CIN-like TCP activity to promote leaf development by mediating the degradation of the TCP repressor TIE1 in Arabidopsis (Zhang et al 2017). Gh_A11G0777 is homologous to AT4G00730, which affects the accumulation of anthocyanin in subepidermal cells and the organization of cells in the primary root in A. thaliana, suggesting that this homeobox gene determines the nature of the epidermis and/or subepidermis (Kubo et al 1999).…”