Cambial activity is a prerequisite for secondary growth in plants; however, regulatory factors controlling the activity of the secondary meristem in radial growth remain elusive. Here, we identified INCREASED CAMBIAL ...Cambial activity is a prerequisite for secondary growth in plants; however, regulatory factors controlling the activity of the secondary meristem in radial growth remain elusive. Here, we identified INCREASED CAMBIAL ACTIVITY (ICA), a gene encoding a putative pectin methyltransferase, which could function as a modulator for the meristematic activity of fascicular and interfascicular cambium in Arabidopsis. An overexpressing transgenic line, 35S:'1CA, showed accelerated stern elongation and radial thickening, resulting in increased accumulation of biomass, and increased levels of cytokinins (CKs) and gibberellins (GAs). Expression of genes encoding pectin methylesterases involved in pectin modification together with pectin methyltransferases was highly induced in 355::ICA, which might contribute to an increase of methanol emission as a byproduct in 35S:ICA. Methanol treatment induced the expression of GA- or CK-responsive genes and stimulated plant growth. Overall, we propose that ectopic expression of ICA increases cambial activity by regulating CK and GA homeostasis, and methanol emission, eventually leading to stem elongation and radial growth in the inflorescence stem.展开更多
Integration of internal and external cues into developmental programs is indispensable for growth and development of plants, which involve complex interplays among signaling pathways activated by the internal and exte...Integration of internal and external cues into developmental programs is indispensable for growth and development of plants, which involve complex interplays among signaling pathways activated by the internal and external factors (IEFs). However, decoding these complex interplays is still challenging. Here, we present a web-based platform that identifies key regulators and Network models delineating Interplays among Developmental signaling (iNID) in Arabidopsis. iNID provides a comprehensive resource of (1) transcriptomes previously collected under the conditions treated with a broad spectrum of IEFs and (2) protein and genetic interactome data in Arabidopsis. In addition, iNID provides an array of tools for identifying key regulators and network models related to interplays among IEFs using transcriptome and interactome data. To demonstrate the utility of iNID, we investigated the interplays of (1) phytohormones and light and (2) phytohormones and biotic stresses. The results revealed 34 potential regulators of the interplays, some of which have not been reported in association with the interplays, and also network models that delineate the involvement of the 34 regulators in the interplays, providing novel insights into the interplays collectively defined by phytohormones, light, and biotic stresses. We then experimentally verified that BME3 and TEM1, among the selected regulators, are involved in the auxin-brassinosteroid (BR)-blue light interplay. Therefore, iNID serves as a useful tool to provide a basis for understanding interplays among IEFs.展开更多
基金the support of “Cooperative Research Program for Agriculture Science & Technology Development (Project No. PJ010953022016)” Rural Development Administration, Korea
文摘Cambial activity is a prerequisite for secondary growth in plants; however, regulatory factors controlling the activity of the secondary meristem in radial growth remain elusive. Here, we identified INCREASED CAMBIAL ACTIVITY (ICA), a gene encoding a putative pectin methyltransferase, which could function as a modulator for the meristematic activity of fascicular and interfascicular cambium in Arabidopsis. An overexpressing transgenic line, 35S:'1CA, showed accelerated stern elongation and radial thickening, resulting in increased accumulation of biomass, and increased levels of cytokinins (CKs) and gibberellins (GAs). Expression of genes encoding pectin methylesterases involved in pectin modification together with pectin methyltransferases was highly induced in 355::ICA, which might contribute to an increase of methanol emission as a byproduct in 35S:ICA. Methanol treatment induced the expression of GA- or CK-responsive genes and stimulated plant growth. Overall, we propose that ectopic expression of ICA increases cambial activity by regulating CK and GA homeostasis, and methanol emission, eventually leading to stem elongation and radial growth in the inflorescence stem.
文摘Integration of internal and external cues into developmental programs is indispensable for growth and development of plants, which involve complex interplays among signaling pathways activated by the internal and external factors (IEFs). However, decoding these complex interplays is still challenging. Here, we present a web-based platform that identifies key regulators and Network models delineating Interplays among Developmental signaling (iNID) in Arabidopsis. iNID provides a comprehensive resource of (1) transcriptomes previously collected under the conditions treated with a broad spectrum of IEFs and (2) protein and genetic interactome data in Arabidopsis. In addition, iNID provides an array of tools for identifying key regulators and network models related to interplays among IEFs using transcriptome and interactome data. To demonstrate the utility of iNID, we investigated the interplays of (1) phytohormones and light and (2) phytohormones and biotic stresses. The results revealed 34 potential regulators of the interplays, some of which have not been reported in association with the interplays, and also network models that delineate the involvement of the 34 regulators in the interplays, providing novel insights into the interplays collectively defined by phytohormones, light, and biotic stresses. We then experimentally verified that BME3 and TEM1, among the selected regulators, are involved in the auxin-brassinosteroid (BR)-blue light interplay. Therefore, iNID serves as a useful tool to provide a basis for understanding interplays among IEFs.