The TIR-NBS 2 (TN2) gene from Arabidopsis thaliana (Arabidopsis), which encodes a TIR (the Toll and Interleukin-1 Receptor)-type of nucleotide binding site (NBS) receptor protein (TIR-NBS) that can cause cell death in...The TIR-NBS 2 (TN2) gene from Arabidopsis thaliana (Arabidopsis), which encodes a TIR (the Toll and Interleukin-1 Receptor)-type of nucleotide binding site (NBS) receptor protein (TIR-NBS) that can cause cell death in the model plant Nicotiana benthamiana (N. benthamiana). Nevertheless, the mechanism of TN2 signal initiation is still unclear. This research performed yeast two-hybrid and bimolecular fluorescence complementation (BIFC) assays to investigate interactions between proteins of TN2, and analyzed the influences of these interactors on TN2 function using N. benthamiana. EXO70B1, SOC3 and CPK5-VK were identified as interacting proteins of TN2 based on yeast two-hybrid and BIFC methods. Functional annotations of these interacting proteins indicate their involvement in multiple pathways, including exocytosis, positive regulation of abscisic acid-activated signaling pathway, regulation of stomatal closure, response to water deprivation, defense response, signal transduction and intracellular signal transduction. The transient assay results proclaimed that EXO70B1 can suppress cell death triggered by TN2 and TN2-TIR. These outcomes suggest that TN2 receptor may be participated in various pathways, and the protein level and activity are strictly controlled at multiple aspects, providing novel clues for elucidating the molecular mechanism of TN2 immune receptor in Arabidopsis resistance.展开更多
E3 ubiquitin ligases are participated in numerous processes, regulating the response to biotic and abiotic stresses. Botrytis susceptible1 interactor (BOI) is a RING (Really Interesting New Gene)-type E3 ligase that m...E3 ubiquitin ligases are participated in numerous processes, regulating the response to biotic and abiotic stresses. Botrytis susceptible1 interactor (BOI) is a RING (Really Interesting New Gene)-type E3 ligase that mediates the ubiquitination of BOS1 (Botrytis susceptible1), a transcription factor involved in stress and pathogen responses. Although BOI is an E3 ligase, there are reports to show that BOI interacts with target proteins such as DELLAs or CONSTANS to repress gibberellin responses and flowering without the degradation of the target proteins. In this article, we utilize diversified methods to comprehensively analyze the expression pattern, interaction network and function of BOI gene. Firstly, 1800 bp upstream region of BOI gene from Arabidopsis thaliana (Arabidopsis) genome was isolated, and fused GUS reporter gene. The resulting expression cassette was introduced into wild-type Arabidopsis through Agrobacterium-mediated transformation. The result demonstrated that BOI gene was expressed predominantly in leaves, siliques, young roots, and flowering tissues, indicating that BOI gene may be involved in multiple processes in plant growth and development in Arabidopsis. Besides, eight candidate interacting proteins were obtained from the Arabidopsis cDNA library via yeast two-hybrid technology, including EXO70E2 (AT5G61010), WRKY7 (AT4G24240), WRKY11 (AT4G31550), WRKY17 (AT2G24570), UBP20 (AT4G17895), L5 (AT1G12290), SAUR9 (AT4G36110) and TCP21 (AT5G08330). Functional analysis of these candidate interacting proteins manifested that they related to multiple pathways, including biological and abiotic stress, programmed cell death, protein degradation, material metabolism and transcriptional regulation. In addition, the results of the transient assay proclaimed that BOI protein affects the protein stability of EXO70E2 and L5 through its E3 ubiquitin ligase activity. Our results provide novel clues for a better understanding of molecular mechanisms underlying BOI-mediated regulations.展开更多
NBS-LRR (nucleotide binding sites and leucine rich repeat) protein plays a crucial role as sentries and as defense activators in plants. The structure and function of NBS-LRR proteins are closely related. Previous art...NBS-LRR (nucleotide binding sites and leucine rich repeat) protein plays a crucial role as sentries and as defense activators in plants. The structure and function of NBS-LRR proteins are closely related. Previous articles have announced that the activated ZAR1 (HopZ-Activated Resistance 1) forms a pentamer in the plasma membrane, which is a calcium permeable channel that can trigger plant immune signaling and cell death. However, the structure of galore NBS-LRRs in Arabidopsis is not yet clear. The functional sites of distinct NBS-LRR in cells may vary. In addition, identifying pathogens and activating defense regions may occur in different subcellular compartments. Therefore, dissecting the specific structure and positioning of NBS-LRRs is an indispensable step in understanding their functions. In this article, we exploit AlphaFold to predict the structure of some designed NBS-LRRs, and utilize Agroinfiltration transient expression system, combined with biochemical fractionation, to dissect the localization of these NBS-LRR receptors from Arabidopsis. Structural data indicates that the identified NBS-LRRs share analogous conformation. Membrane fractionation assay demonstrates these NBS-LRRs are mainly associated with the membrane. These data show that the Ca2+-permeable channel activity may be evolutionarily conserved in NBS-LRR of Arabidopsis, and this study provides some reference clues for analyzing the structure and localization patterns of other plant immune receptors.展开更多
文摘The TIR-NBS 2 (TN2) gene from Arabidopsis thaliana (Arabidopsis), which encodes a TIR (the Toll and Interleukin-1 Receptor)-type of nucleotide binding site (NBS) receptor protein (TIR-NBS) that can cause cell death in the model plant Nicotiana benthamiana (N. benthamiana). Nevertheless, the mechanism of TN2 signal initiation is still unclear. This research performed yeast two-hybrid and bimolecular fluorescence complementation (BIFC) assays to investigate interactions between proteins of TN2, and analyzed the influences of these interactors on TN2 function using N. benthamiana. EXO70B1, SOC3 and CPK5-VK were identified as interacting proteins of TN2 based on yeast two-hybrid and BIFC methods. Functional annotations of these interacting proteins indicate their involvement in multiple pathways, including exocytosis, positive regulation of abscisic acid-activated signaling pathway, regulation of stomatal closure, response to water deprivation, defense response, signal transduction and intracellular signal transduction. The transient assay results proclaimed that EXO70B1 can suppress cell death triggered by TN2 and TN2-TIR. These outcomes suggest that TN2 receptor may be participated in various pathways, and the protein level and activity are strictly controlled at multiple aspects, providing novel clues for elucidating the molecular mechanism of TN2 immune receptor in Arabidopsis resistance.
文摘E3 ubiquitin ligases are participated in numerous processes, regulating the response to biotic and abiotic stresses. Botrytis susceptible1 interactor (BOI) is a RING (Really Interesting New Gene)-type E3 ligase that mediates the ubiquitination of BOS1 (Botrytis susceptible1), a transcription factor involved in stress and pathogen responses. Although BOI is an E3 ligase, there are reports to show that BOI interacts with target proteins such as DELLAs or CONSTANS to repress gibberellin responses and flowering without the degradation of the target proteins. In this article, we utilize diversified methods to comprehensively analyze the expression pattern, interaction network and function of BOI gene. Firstly, 1800 bp upstream region of BOI gene from Arabidopsis thaliana (Arabidopsis) genome was isolated, and fused GUS reporter gene. The resulting expression cassette was introduced into wild-type Arabidopsis through Agrobacterium-mediated transformation. The result demonstrated that BOI gene was expressed predominantly in leaves, siliques, young roots, and flowering tissues, indicating that BOI gene may be involved in multiple processes in plant growth and development in Arabidopsis. Besides, eight candidate interacting proteins were obtained from the Arabidopsis cDNA library via yeast two-hybrid technology, including EXO70E2 (AT5G61010), WRKY7 (AT4G24240), WRKY11 (AT4G31550), WRKY17 (AT2G24570), UBP20 (AT4G17895), L5 (AT1G12290), SAUR9 (AT4G36110) and TCP21 (AT5G08330). Functional analysis of these candidate interacting proteins manifested that they related to multiple pathways, including biological and abiotic stress, programmed cell death, protein degradation, material metabolism and transcriptional regulation. In addition, the results of the transient assay proclaimed that BOI protein affects the protein stability of EXO70E2 and L5 through its E3 ubiquitin ligase activity. Our results provide novel clues for a better understanding of molecular mechanisms underlying BOI-mediated regulations.
文摘NBS-LRR (nucleotide binding sites and leucine rich repeat) protein plays a crucial role as sentries and as defense activators in plants. The structure and function of NBS-LRR proteins are closely related. Previous articles have announced that the activated ZAR1 (HopZ-Activated Resistance 1) forms a pentamer in the plasma membrane, which is a calcium permeable channel that can trigger plant immune signaling and cell death. However, the structure of galore NBS-LRRs in Arabidopsis is not yet clear. The functional sites of distinct NBS-LRR in cells may vary. In addition, identifying pathogens and activating defense regions may occur in different subcellular compartments. Therefore, dissecting the specific structure and positioning of NBS-LRRs is an indispensable step in understanding their functions. In this article, we exploit AlphaFold to predict the structure of some designed NBS-LRRs, and utilize Agroinfiltration transient expression system, combined with biochemical fractionation, to dissect the localization of these NBS-LRR receptors from Arabidopsis. Structural data indicates that the identified NBS-LRRs share analogous conformation. Membrane fractionation assay demonstrates these NBS-LRRs are mainly associated with the membrane. These data show that the Ca2+-permeable channel activity may be evolutionarily conserved in NBS-LRR of Arabidopsis, and this study provides some reference clues for analyzing the structure and localization patterns of other plant immune receptors.
