WOX11 and CRL1 act synergistically to promote crown root development by maintaining cytokinin homeostasis in rice

Abstract

Crown root (CR) morphogenesis is critical for normal growth and nutrition absorption in cereals. In rice, WUSCHEL-RELATED HOMEOBOX11 (WOX11) and CROWN ROOTLESS1 (CRL1) play vital roles in controlling CR development. Despite their importance, whether and how the two regulators coordinate CR formation remains unclear.Electrophoretic mobility shift assays, transient expression, and chromatin immunoprecipitation qPCR suggested that WOX11 and CRL1 directly bind to OsCKX4 to regulate its expression during CR development.CRL1 enhances OsCKX4 activation through direct interaction with WOX11 at root emergence and elongation stages. Genetic dissection showed that the wox11/crl1 double mutant exhibits a more severe root phenotype. OsCKX4 knockout plants generated by CRISPR/Cas9 exhibited fewer CRs and higher cytokinin levels in the root meristem. Increased expression of OsCKX4 could partially complement the CR phenotypes of both crl1 and wox11 mutants. Furthermore, cytokinin can promote WOX11 protein accumulation in the root meristem.Together, these findings show that cytokinin accumulation is tightly regulated by the WOX11-CRL1 complex during CR elongation by counteracting the negative regulatory effects of cytokinin on root development. Importantly, these results reveal an intrinsic link between WOX11 protein accumulation and cytokinin to maintain CR growth.

Integrated transgene and transcriptome reveal the molecular basis of MdWRKY87 positively regulate adventitious rooting in apple rootstock

“…It is well known auxin and cytokinin appear to play antagonistic roles in the adventitious rooting process. Among these TF and TR genes family, previous study has demonstrated that AUX/IAAs , AINTEGUMENTA ( ANT ), AINTEGUMENTA LIKE1 ( AIL ), WUSCHEL-RELATED HOMEOBOX ( WOX ), and type-B cytokinin Response Regulator ( RR ) family genes involved in adventitious rooting process ( Ramírez-Carvajal et al., 2009 ; Rigal et al., 2012 ; Lakehal et al., 2019 ; Geng et al., 2023 ). In genes up-regulated by MdWRKY87 , WUSCHEL-RELATED HOMEOBOX11 ( WOX11 ), and AINTEGUMENTA LIKE1 ( AIL ) are positive regulators of adventitious root formation.…”

“…A set of 272 overlapping DEGs were identified through GO enrichment analysis, implying their potential importance for MdWRKY87-dependent adventitious rooting formation (Figure 6B). Among these DEGs, we found MdWRKY87 overexpression can activate the expression of adventitious rooting-induced genes, such as WOX11 and AIL, and the counterparts of WOX11 and AIL promote adventitious root formation in A.thaliana and poplar (Rigal et al, 2012;Hu and Xu, 2016;Geng et al, 2023). In addition, MdWRKY87 overexpression can inhibit the transcription of adventitious rootingrepressed genes, such as AUX/IAAs and RRs, and the counterparts of AUX/IAAs and type-B RRs inhibit adventitious root formation in Arabidopsis, apple, and poplar (Ramıŕez-Carvajal et al, 2009;Lakehal et al, 2019;Zhao et al, 2020).…”

OsMADS5 interacts with OsSPL14/17 to inhibit rice root elongation by restricting cell proliferation of root meristem under ammonium supply

“…(2015) and Geng et al. (2023) using an EdU kit. The SR were treated with a 50 m m EdU solution for 3 h, and subsequently fixed in 4% paraformaldehyde for 30 min.…”

“…The EdU staining method was conducted following the protocols of Li et al (2015) and Geng et al (2023) using an EdU kit. The SR were treated with a 50 mM EdU solution for 3 h, and subsequently fixed in 4% paraformaldehyde for 30 min.…”

Genome-Wide Identification and Abiotic-Stress-Responsive Expression of CKX Gene Family in Liriodendron chinense

“…Cytokinins play opposite roles in shoot apical meristems (SAMs) and root apical meristems (RAMs). Plants with lowered cytokinin signal output or cytokinin content form larger RAMs and exhibit more rapidly growing roots [3,4]. Plant CKs promote developmental and physiological processes, drought tolerance, root architecture, and ultimately, crop productivity.…”