The Implementation of the 2020 Roadmap to Promote Good Registration Management (GRM) in APEC Region.

BACKGROUND: To promote the efficiency and quality of registration for medical products, the Asia-Pacific Economic Cooperation (APEC) Regulatory Harmonization Steering Committee (RHSC) has implemented a 2020 roadmap to promote the concept of GRM since 2011. Key outcomes of this roadmap are discussed in this article to provide recommendations for improved regulatory practices and accelerated regulatory convergence. METHODS: Adoption of relevant guidelines and delivery of training programs from the APEC Training Centers of Excellence for Regulatory Science (CoEs) have played a key role to promote capacity building, cooperation and convergence in good review practices (GRevPs) and good submission practices (GSubPs) for medical products among APEC economies. A key performance indicator (KPI) survey among the drug regulatory authorities (RAs) of APEC economies was conducted to understand the progress of this roadmap. RESULTS: The CoE programs have provided a unique opportunity to promote dialogues between regulatory authorities and industry and efficiently disseminated the concept of GRM among APEC economies. The results of the KPI survey indicated significant progress in the status of implementing GRevPs over the last ten years. CONCLUSIONS: To accelerate regulatory convergence among APEC economies, it is necessary to promote mutual trust and cooperation in approval of medical products over the time. Continuous training in GRevPs and GSubPs through the CoE platform would set the stage to achieve the goal in the next decade.

Ethylene response pathway is essential for ARABIDOPSIS A-FIFTEEN function in floral induction and leaf senescence.

ARABIDOPSIS A-FIFTEEN (AAF) encodes a plastid protein and was originally identified as a SENESCENCE-ASSOCIATED GENE. Previously, we found that overexpression of AAF (AAF-OX) in Arabidopsis led to accumulated reactive oxygen species and promoted leaf senescence induced by oxidative stress, which was suppressed by a null mutant, ein2-5, in ethylene response pathway. Whether AAF function is involved in ethylene biosynthesis and/or the response pathway remained unknown. Here we show that neither overexpression (AAF-OX) nor a null mutant (aaf-KO) of AAF generates a higher level of ethylene than the wild type and display a typical triple-response phenotype in etiolated seedlings treated with 1-aminocyclopropane-1-carboxylic acid (ACC). Nevertheless, ein2-5 suppresses the phenotypes of early flowering and age-dependent leaf senescence in AAF-OX plants. We reveal that a functional ethylene response is essential for AAF function in leaf senescence and floral induction, but AAF is unlikely a regulatory component integral to the ethylene pathway.

Role of ARABIDOPSIS A-FIFTEEN in regulating leaf senescence involves response to reactive oxygen species and is dependent on ETHYLENE INSENSITIVE2.

Leaf senescence is a highly regulated developmental process that is coordinated by several factors. Many senescence-associated genes (SAGs) have been identified, but their roles during senescence remain unclear. A sweet potato (Ipomoea batatas) SAG, named SPA15, whose function was unknown, was identified previously. To understand the role of SPA15 in leaf senescence further, the orthologue of SPA15 in Arabidopsis thaliana was identified and characterized, and it was named ARABIDOPSIS A-FIFTEEN (AAF). AAF was expressed in early senescent leaves and in tissues with highly proliferative activities. AAF was localized to the chloroplasts by transient expression in Arabidopsis mesophyll protoplasts. Overexpression of AAF (AAF-OX) in Arabidopsis promoted, but the T-DNA insertion mutant (aaf-KO), delayed age-dependent leaf senescence. Furthermore, stress-induced leaf senescence caused by continuous darkness was enhanced in AAF-OX but suppressed in aaf-KO. Transcriptome analysis of expression profiles revealed up-regulated genes related to pathogen defence, senescence, and oxidative stress in 3-week-old AAF-OX plants. Indeed, elevated levels of reactive oxygen species (ROS) and enhanced sensitivity to oxidative and dark stress were apparent in AAF-OX but reduced in aaf-KO. ETHYLENE INSENSITIVE2 (EIN2) was required for the dark- and ROS-induced senescence phenotypes in AAF-OX and the induction of AAF expression by treatment with the immediate precursor of ethylene, 1-aminocyclopropane-1-carboxylic acid. The results indicate the functional role of AAF is an involvement in redox homeostasis to regulate leaf senescence mediated by age and stress factors during Arabidopsis development.