Rose(Rosa hybrida)plants are major ornamental species worldwide,and their commercial value greatly depends on their open flowers,as both the quality of fully open petals and long vase life are important.Petal senescen...Rose(Rosa hybrida)plants are major ornamental species worldwide,and their commercial value greatly depends on their open flowers,as both the quality of fully open petals and long vase life are important.Petal senescence can be started and accelerated by various hormone signals,and ethylene is considered an accelerator of petal senescence in rose.To date,however,the underlying mechanism of signaling crosstalk between ethylene and other hormones such as JA in petal senescence remains largely unknown.Here,we isolated RhMYB108,an R2R3-MYB transcription factor,which is highly expressed in senescing petals as well as in petals treated with exogenous ethylene and JA.Applications of exogenous ethylene and JA markedly accelerated petal senescence,while the process was delayed in response to applications of 1-MCP,an ethylene action inhibitor.In addition,silencing of RhMYB108 alter the expression of SAGs such as RhNAC029,RhNAC053,RhNAC092,RhSAG12,and RhSAG113,and finally block ethylene-and JA-induced petal senescence.Furthermore,RhMYB108 was identified to target the promoters of RhNAC053,RhNAC092,and RhSAG113.Our results reveal a model in which RhMYB108 functions as a receptor of ethylene and JA signals to modulate the onset of petal senescence by targeting and enhancing senescence-associated gene expression.展开更多
Surface plasmon resonance(SPR) systems are widely used for detailed characterization of antibody activities including antigen and Fc-receptor binding. During the later stages of development, where the focus is to ensu...Surface plasmon resonance(SPR) systems are widely used for detailed characterization of antibody activities including antigen and Fc-receptor binding. During the later stages of development, where the focus is to ensure that established critical quality attributes(CQAs) are maintained during cell culture,purification and formulation processes, analysis is simplified, and relative potencies are often determined. Here, simulation of binding data revealed that relative potency values, determined via parallel line analysis(PLA) and half maximal effective concentration(EC50) analysis accurately reflect changes in active concentration only if binding kinetics remain unchanged. Changes in the association rate constant shifted dose response curves, and therefore relative potencies, in the same way as changes in analyte concentration do. However, for interactions characterized by stable binding, changes in the dissociation rate constant did not result in any shift, suggesting that this type of change may go unnoticed in the dose response curve. Thus, EC50 and PLA analyses of dose response curves obtained with an anti-TNF-α antibody were complemented with the Biacore functionality for sensorgram comparison analysis, whereby changes in antigen and Fc-receptor binding profiles could be detected. Next, analysis of temperature stressed TNF-α antibody revealed that calibration free concentration analysis(CFCA) data correlated perfectly with relative potency values. Together, these results demonstrate that combinations of SPR based dose response curves, sensorgram comparison and CFCA can be used to strengthen the confidence in relative potency assessments, and suggest that SPR can potentially be used as a surrogate potency assay in the quality control of biotherapeutic medicines.展开更多
基金supported by the National Natural Science Foundation of China(Grant Nos.31572162 and 31902054)the School Project of Shenzhen Polytechnic(No.601822K27003).
文摘Rose(Rosa hybrida)plants are major ornamental species worldwide,and their commercial value greatly depends on their open flowers,as both the quality of fully open petals and long vase life are important.Petal senescence can be started and accelerated by various hormone signals,and ethylene is considered an accelerator of petal senescence in rose.To date,however,the underlying mechanism of signaling crosstalk between ethylene and other hormones such as JA in petal senescence remains largely unknown.Here,we isolated RhMYB108,an R2R3-MYB transcription factor,which is highly expressed in senescing petals as well as in petals treated with exogenous ethylene and JA.Applications of exogenous ethylene and JA markedly accelerated petal senescence,while the process was delayed in response to applications of 1-MCP,an ethylene action inhibitor.In addition,silencing of RhMYB108 alter the expression of SAGs such as RhNAC029,RhNAC053,RhNAC092,RhSAG12,and RhSAG113,and finally block ethylene-and JA-induced petal senescence.Furthermore,RhMYB108 was identified to target the promoters of RhNAC053,RhNAC092,and RhSAG113.Our results reveal a model in which RhMYB108 functions as a receptor of ethylene and JA signals to modulate the onset of petal senescence by targeting and enhancing senescence-associated gene expression.
文摘Surface plasmon resonance(SPR) systems are widely used for detailed characterization of antibody activities including antigen and Fc-receptor binding. During the later stages of development, where the focus is to ensure that established critical quality attributes(CQAs) are maintained during cell culture,purification and formulation processes, analysis is simplified, and relative potencies are often determined. Here, simulation of binding data revealed that relative potency values, determined via parallel line analysis(PLA) and half maximal effective concentration(EC50) analysis accurately reflect changes in active concentration only if binding kinetics remain unchanged. Changes in the association rate constant shifted dose response curves, and therefore relative potencies, in the same way as changes in analyte concentration do. However, for interactions characterized by stable binding, changes in the dissociation rate constant did not result in any shift, suggesting that this type of change may go unnoticed in the dose response curve. Thus, EC50 and PLA analyses of dose response curves obtained with an anti-TNF-α antibody were complemented with the Biacore functionality for sensorgram comparison analysis, whereby changes in antigen and Fc-receptor binding profiles could be detected. Next, analysis of temperature stressed TNF-α antibody revealed that calibration free concentration analysis(CFCA) data correlated perfectly with relative potency values. Together, these results demonstrate that combinations of SPR based dose response curves, sensorgram comparison and CFCA can be used to strengthen the confidence in relative potency assessments, and suggest that SPR can potentially be used as a surrogate potency assay in the quality control of biotherapeutic medicines.