Brassinosteroids-mediated regulation of ABI3 is involved in high-temperature induced early flowering in plants

Hong, Jeongeui,Sung, Jwakyung,Ryu, Hojin The Korean Society of Plant Biotechnology 2018 식물생명공학회지 Vol.45 No.2

The interplay of plant hormones is one of the essential mechanisms for plant growth and development. A recent study reported that Brassinosteroids (BR) and ABSCISIC ACID (ABA) interact antagonistically in early seedling developments through the BR-mediated epigenetic repression of ABSCISIC ACID-INSENSITIVE 3 (ABI3). However, the other physiological roles of the BR-mediated regulation of ABI3 and ABA responses beyond early seedling developments remain largely unknown. Here, we showed that the activation of BR signaling by high temperatures promotes flowering time through the suppression of ABI3 expressions. Elevated ambient temperature induced early flowering in wild type Col-0 plants, but not in BR-defective bri1-116 mutant plants. Conversely, a hyper BR biosynthetic dwf4-D mutant displayed more sensitive thermomorphic long shoot elongation and early flowering. Both expression patterns and physiological responses supported the biological roles of ABI3 in the regulation of floral transition and reproduction under high temperature conditions. Finally, we confirmed that the lowered expressions of the transcript and protein levels of ABI3 brought on by elevated temperature were correlated with warmth-induced early flowering phenotypes. In conclusion, our data suggest that the BR- and warmth-mediated regulation of ABI3 are important in thermomorphic reproductive phase transitions in plants.

Identification of ABSCISIC ACID (ABA) signaling related genes in Panax ginseng

Hong, Jeongeui,Kim, Hogyum,Ryu, Hojin The Korean Society of Plant Biotechnology 2018 식물생명공학회지 Vol.45 No.4

Korean ginseng (Panax ginseng) has long been cultivated as an important economic medicinal plant. Owing to the seasonal and long-term agricultural cultivation methods of Korean ginseng, they are always vulnerable to various environmental stress conditions. ABSCISIC ACID (ABA) is an essential plant hormone associated with seed development and diverse abiotic stress responses including drought, cold and salinity stress. By modulating ABA responses, plants can regulate their immune responses and growth patterns to increase their ability to tolerate stress. With recent advances in genome sequencing technology, we first reported the functional features of genes related to canonical ABA signaling pathway in P. ginseng genome. Based on the protein sequences and functional genomic analysis of Arabidopsis thaliana, the ABA related genes were successfully identified. Our functional genomic characterizations clearly showed that the ABA signaling related genes consisting the ABA receptor proteins (PgPYLs), kinase family (PgSnRKs) and transcription factors (PgABFs, PgABI3s and PgABI5s) were evolutionary conserved in the P. ginseng genome. We confirmed that overexpressing ABA related genes of P. ginseng completely restored the ABA responses and stress tolerance in ABA defective Arabidopsis mutants. Finally, tissue and age specific spatio-temporal expression patterns of the identified ABA-related genes in P. ginseng tissues were also classified using various available RNA sequencing data. This study provides ABA signal transduction related genes and their functional genomic information related to the growth and development of Korean ginseng. Additionally, the results of this study could be useful in the breeding or artificial selection of ginseng which is resistant to various stresses.

Identification and functional analysis of COLD-signaling-related genes in Panax ginseng

Jeongeui Hong,Hojin Ryu The Korean Society of Plant Biotechnology 2023 JOURNAL OF PLANT BIOTECHNOLOGY Vol.50 No.1

Cold stress is one of the most vulnerable environmental stresses that affect plant growth and crop yields. With the recent advancements in genetic approaches using Arabidopsis and other model systems, genes involved in cold-stress response have been identified and the key cold signaling factors have been characterized. Exposure to low-temperature stress triggers the activation of a set of genes known as cold regulatory (COR) genes. This activation process plays a crucial role in enhancing the resistance of plants to cold and freezing stress. The inducer of the C-repeatbinding factor (CBF) expression 1-CBF module (ICE1-CBF module) is a key cold signaling pathway regulator that enhances the expression of downstream COR genes; however, this signaling module in Panax ginseng remains elusive. Here, we identified cold-signaling-related genes, PgCBF1, PgCBF3, and PgICE1 and conducted functional genomic analysis with a heterologous system. We confirmed that the overexpression of cold- PgCBF3 in the cbf1/2/3 triple Arabidopsis mutant compensated for the cold stress-induced deficiency of COR15A and salt-stress tolerance. In addition, nuclearlocalized PgICE1 has evolutionarily conserved phosphorylation sites that are modulated by brassinsteroid insensitive 2 (PgBIN2) and sucrose non-fermenting 1 (SNF1)-related protein kinase 3 (PgSnRK3), with which it physically interacted in a yeast two-hybrid assay. Overall, our data reveal that the regulators identified in our study, PgICE1 and PgCBFs, are evolutionarily conserved in the P. ginseng genome and are functionally involved in cold and abiotic stress responses.

결정질 실리콘 태양광 사업현황 및 양산기술 과제와 개발방향

홍정의(JeongEui Hong) 한국신재생에너지학회 2017 한국신재생에너지학회 학술대회논문집 Vol.2017 No.5

Identification and functional analysis of COLD-signaling-related genes in Panax ginseng

홍정의(Jeongeui Hong),류호진(Hojin Ryu) (사)한국식물생명공학회 2023 JOURNAL OF PLANT BIOTECHNOLOGY Vol.50 No.4

해시함수를 활용한 페이스북 게시물 조작 알림 시스템 구축

홍정의(Jeongeui Hong) 한국정보과학회 2019 한국정보과학회 학술발표논문집 Vol.2019 No.6

Thermally Stable Tungsten Bit-line Process Flow for the Capacitor Over Bit-line-Type Dynamic Random-Access Memory

LEE, Won-Jun,HONG, Jeongeui,RHA, Sa-Kyun 대전산업대학교 반도체기술연구소 2000 半導體技術硏究所報 Vol.2 No.-

Thermally stable tungsten(W) bit-line process technology has been successfully integrated for capacitor over bit-line(COB)-type dynamic random-access memory(DRAM). Major parameters of the W bit-line process flow are demonstrated to be the Ti thickness, the silicidation temperature and the dopant concentration. The minimum contract resistance (<1000Ω) of the W bit-line into the p+ active region has been obtained by the silicidation of this Ti(7nm) at a high temperature (800℃) with the additional ion implantation of BF^+_2 after the contact formation. The effects of the process parameters were explained in terms of the agglomeration of the Ti silicide and dopant concentration in the silicon active region.

유식물 발달과정에서 브라시노스테로이드와 앱시스산 신호전달의 상호작용 연구

김혜민,홍정의,조용구,강권규,류호진,Kim, Hyemin,Hong, Jeongeui,Cho, Yong-Gu,Kang, Kwon Kyoo,Ryu, Hojin 한국식물생명공학회 2017 식물생명공학회지 Vol.44 No.3

식물의 유일한 활성 스테로이드 호르몬인 Brassinosteroid (BR)는 다양한 내재적 또는 외부 신호 전달 경로와의 통합적인 결합을 통해 식물의 생장 및 발달 과정에서 중요한 기능을 하는 것으로 알려져 있다. 최근 식물학 연구들은 종자의 발아와 초기 발달과정에서 BR과 ABA 사이의 필수적인 상호작용 메커니즘이 존재하고 있음을 보고하고 있다. 하지만 이들 두 호르몬의 중요한 신호전달 상호작용에 대한 분자 메커니즘은 거의 알려지지 않았다. 식물의 초기 발달과정에서 BR에 의해 매개되는 ABA 신호전달과의 기능학적, 생물학적 상호작용 네트워크를 이해하기 위해 Agilent Arabidopsis $4{\times}44K$ 올리고 칩을 사용하여 비교 전사체 분석을 수행하였다. ABA에 반응하지 않는 bes1-D 돌연변이체에서의 ABA 처리에 따른 다양한 유전자의 발현 패턴을 야생형 식물과 비교 분석하였다. 그 결과 발현의 변화가 발생하는 유전자(DEGs) 2,353개를 확인하였다. GO 분석을 통해 ABA 신호전달 및 대사에 관여하는 유전자들이 BR 신호전달 경로에 의해 하향 조절되는 것으로 확인되었다. 뿐만 아니라, BR 신호전달 경로는 다양한 비생물학적/생물학적 스트레스, 오옥신 및 ROS 등 다양한 신호전달 체계와 밀접하게 연관되어 있음을 확인하였다. 본 연구를 통해 BR 신호전달의 활성화는 ABA 신호전달에 관여하는 다양한 유전자들의 발현을 억제함을 확인하였다. 또한 본 연구는 다양한 신호 경로 사이의 상호작용이 다양한 환경요인에 대한 식물의 적응 반응에 중요하게 작용할 수 있음을 보여주고 있다. Brassinosteroid (BR), a plant steroid hormone, plays a critical role in the growth and developmental processes through its canonical signaling and crosstalk with various internal and external signaling pathways. Recent studies have revealed the essential interplay mechanisms between BR and ABA during seed germination and early seedling establishment. However, molecular mechanisms for this important signaling crosstalk are largely unknown. To understand the crosstalk between BR-mediated signaling pathways and ABA functions during early seedling development, we carried out a comparative genome-wide transcriptome analysis with an Agilent Arabidopsis $4{\times}44K$ oligo chip. We selected and compared the expression patterns of ABA response genes in ABA-insensitive bes1-D mutant with wild type seedlings on which ABA was exogenously applied. As a result, we identified 2,353 significant differentially expressed genes (DEGs) in ABA-treated bes1-D and wild type seedlings. GO enrichment analysis revealed that ABA signaling, response, and metabolism were critically down-regulated by BR-activated signaling pathways. In addition, the genome-wide transcriptome analysis data revealed that BR-regulated signaling pathways were tightly connected to diverse signal cues including abiotic/biotic stress, auxin, ROS etc. In this study, we newly identified the molecular mechanisms of BR-mediated repression of ABA signaling outputs. Also, our data suggest that interplay among diverse signaling pathways is critical for the adaptive response of the plant to various environmental factors.

Cytokinin signaling promotes root secondary growth and bud formation in Panax ginseng

Kyoung Rok Geem,Yookyung Lim,Jeongeui Hong,Wonsil Bae,Jinsu Lee,Soeun Han,Jinsu Gil,Hyunwoo Cho,Hojin Ryu The Korean Society of Ginseng 2024 Journal of Ginseng Research Vol.48 No.2

Background: Panax ginseng, one of the valuable perennial medicinal plants, stores numerous pharmacological substrates in its storage roots. Given its perennial growth habit, organ regeneration occurs each year, and cambium stem cell activity is necessary for secondary growth and storage root formation. Cytokinin (CK) is a phytohormone involved in the maintenance of meristematic cells for the development of storage organs; however, its physiological role in storage-root secondary growth remains unknown. Methods: Exogenous CK was repeatedly applied to P. ginseng, and morphological and histological changes were observed. RNA-seq analysis was used to elucidate the transcriptional network of CK that regulates P. ginseng growth and development. The HISTIDINE KINASE 3 (PgHK3) and RESPONSE REGULATOR 2 (PgRR2) genes were cloned in P. ginseng and functionally analyzed in Arabidopsis as a two-component system involved in CK signaling. Results: Phenotypic and histological analyses showed that CK increased cambium activity and dormant axillary bud formation in P. ginseng, thus promoting storage-root secondary growth and bud formation. The evolutionarily conserved two-component signaling pathways in P. ginseng were sufficient to restore CK signaling in the Arabidopsis ahk2/3 double mutant and rescue its growth defects. Finally, RNA-seq analysis of CK-treated P. ginseng roots revealed that plant-type cell wall biogenesis-related genes are tightly connected with mitotic cell division, cytokinesis, and auxin signaling to regulate CK-mediated P. ginseng development. Conclusion: Overall, we identified the CK signaling-related two-component systems and their physiological role in P. ginseng. This scientific information has the potential to significantly improve the field-cultivation and biotechnology-based breeding of ginseng.

에미터 랩쓰루 실리콘 태양전지 개발

조재억(Jaeeock Cho),양병기(Byungki Yang),이홍구(Honggu Lee),현덕환(Deochwan Hyun),정우원(Woowon Jung),이대종(Daejong Lee),홍근기(Keunkee Hong),이성은(Seong-Eun Lee),홍정의(Jeongeui Hong) 한국태양광발전학회 2013 Current Photovoltaic Research Vol.1 No.1

In contrast to conventional crystalline cells, back-contact solar cells feature high efficiencies, simpler module assembly, and better aesthetics. The highest commercialized cell and module efficiency was recorded by n-type back-contact solar cells. However, the mainstream PV industry uses a p?type substrate instead of n-type due to the high costs and complexity of the manufacturing processes in the case of the latter. P-type back-contact solar cells such as metal wrap?through and emitter wrap-through, which are inexpensive and compatible with the current PV industry, have consequently been developed. In this paper the characteristics of EWT (emitter wrapthrough) solar cells and their status and prospects for development are discussed.