Rice PHYTOCHROME-INTERACTING FACTOR-LIKE 11 (OsPIL11) represses rice tillering by promoting TEOSINTE BRANCHED1 (OsTB1) expression. TaPIL1-MYC and TaSP元-Flag were immunoprecipitated with anti-MYC antibodies, and immunoblots were probed with anti-MYC or anti-Flag antibodies. benthamiana leaves showing the interaction between TaPIL1 and TaSP元. benthamiana leaves showing the interaction between TaPIL1 and TaSP元/17. (c) Luciferase (LUC) complementation imaging assays of N. benthamiana leaves, which were used as the experimental group. The TaSP元-nYFP/TaPIL1-cYFP and TaSPL17-nYFP/TaPIL1-cYFP constructs were infiltrated into the lower right quarter of corresponding N. The four coexpressed samples were used as the negative controls in this assay. nYFP/cYFP, nYFP/TaPIL1-cYFP, and TaSP元-nYFP/cYFP or TaSPL17-nYFP/cYFP constructs were separately infiltrated into the upper left, upper right, and lower left parts of N. (a, b) Bimolecular fluorescence complementation assays of Nicotiana benthamiana leaves showing the interaction between TaPIL1 and TaSP元/17. Physical interaction assays for wheat PHYTOCHROME-INTERACTING FACTOR-LIKE 1 (TaPIL1) and SQUAMOSA PROMOTER BINDING PROTEIN-LIKE (TaSPL)3/17. Error bars denote AESD (**, P < 0.01, Student's t test). The TaGAPDH gene was used as an internal reference. (e) Expression levels of TaPIL1 in the KN199 and TaPIL1-SRDX plants by quantitative reverse transcription PCR at the heading stage. (d) TaPIL1 increases wheat tiller number by the addition of the SUPERMAN repression domain (SRDX) motif. Error bars denote AESD (*, P < 0.05 **, P < 0.01, Student's t test). Values represent the relative fold enrichment of the fragments between TaPIL1-Flag and KN199. The precipitated DNA was analyzed by qPCR. Chromatin in TaPIL1-Flag and KN199 stem base tissues at the jointing stage was immunoprecipitated using anti-Flag antibodies. Schematic representation of different regions, which include the E-box in the promoter of the TaTB1-4A gene. (c) Chromatin immunoprecipitation quantitative PCR (qPCR) showing the enrichment of TaPIL1 on the promoter of TaTB1-4A. (b) Tiller numbers and plant height of cv Kenong 199 (KN199) and TaPIL1-Flag plants at the mature stage (n 15). (a) Morphology of the TaPIL1-Flag transgenic plants at the heading stage. Wheat PHYTOCHROME-INTERACTING FACTOR-LIKE 1 (TaPIL1) associates with the promoter of TEOSINTE BRANCHED1-4A (TaTB1-4A). Yellow fluorescent protein (YFP) was used as a negative control instead of TaPIL1. The relative luciferase activities in different samples were calculated by normalizing the LUC values against REN. The activities of firefly luciferase (LUC) and Renilla luciferase (REN) were determined 18 h posttransformation. (d) Transient expression assays of Nicotiana benthamiana protoplasts showing that TaPIL1 could activate the transcription of TaTB1 genes. (c) Schematic diagrams show the reporters and effectors used in the transient transactivation assays. SD-W indicates synthetic dextrose medium lacking tryptophan (W) SD-W/H indicates synthetic dextrose medium lacking tryptophan (W) and histidine (H). (b) Yeast assays showing the transcriptional activation activity of full-length and truncated TaPIL1. TaPIL1-N, amino terminal domain of TaPIL1 TaPIL1-M, middle region of TaPIL1 TaPIL1-C, carboxyl terminal domain of TaPIL1. (a) Schematic diagrams representing the full-length and truncated TaPIL1 proteins. Wheat PHYTOCHROME-INTERACTING FACTOR-LIKE (TaPIL1) activates the transcription of TEOSINTE BRANCHED1 (TaTB1) genes. This study reveals that PIL family transcription factors directly interact with SPLs and play an important role in repressing tillering/branching in plants. In Arabidopsis, we demonstrate that PIF4 interacts with SPL9 to inhibit shoot branching. In rice, overexpression and loss‐of‐function mutations of OsPIL11 reduce or increase tiller number by regulating the expression of OsTB1. Furthermore, we show that TaPIL1 activates the transcriptional expression of TaTB1 moreover, TaPIL1 physically interacts with TaSP元/17, which are activators of TaTB1 transcription. Overexpression of TaPIL1 reduces wheat tiller number additionally, overexpression of TaPIL1‐SRDX increases wheat tiller number. We found that the PIF‐like protein TaPIL1 controls tiller number in wheat. Using biochemical and genetic approaches, we explore the roles of TaPIL1 in regulating wheat plant architecture. In this study, we identified the PHYTOCHROME‐INTERACTING FACTOR‐LIKE (PIL) family transcription factors as new repressors of tillering in cereal crops. Tillering is an important parameter of plant architecture in cereal crops.

Srdx transcription