Pancreatic β-cell mitophagy as an adaptive response to metabolic stress and the underlying mechanism that involves lysosomal Ca2+ release

Oh Soo-Jin,Park Kihyoun,Sonn Seong Keun,Oh Goo Taeg,Lee Myung-Shik 생화학분자생물학회 2023 Experimental and molecular medicine Vol.55 No.-

Mitophagy is an excellent example of selective autophagy that eliminates damaged or dysfunctional mitochondria, and it is crucial for the maintenance of mitochondrial integrity and function. The critical roles of autophagy in pancreatic β-cell structure and function have been clearly shown. Furthermore, morphological abnormalities and decreased function of mitochondria have been observed in autophagy-deficient β-cells, suggesting the importance of β-cell mitophagy. However, the role of authentic mitophagy in β-cell function has not been clearly demonstrated, as mice with pancreatic β-cell-specific disruption of Parkin, one of the most important players in mitophagy, did not exhibit apparent abnormalities in β-cell function or glucose homeostasis. Instead, the role of mitophagy in pancreatic β-cells has been investigated using β-cell-specific Tfeb-knockout mice (TfebΔβ-cell mice); Tfeb is a master regulator of lysosomal biogenesis or autophagy gene expression and participates in mitophagy. TfebΔβ-cell mice were unable to adaptively increase mitophagy or mitochondrial complex activity in response to high-fat diet (HFD)-induced metabolic stress. Consequently, TfebΔβ-cell mice exhibited impaired β-cell responses and further exacerbated metabolic deterioration after HFD feeding. TFEB was activated by mitochondrial or metabolic stress-induced lysosomal Ca2+ release, which led to calcineurin activation and mitophagy. After lysosomal Ca2+ release, depleted lysosomal Ca2+ stores were replenished by ER Ca2+ through ER→lysosomal Ca2+ refilling, which supplemented the low lysosomal Ca2+ capacity. The importance of mitophagy in β-cell function was also demonstrated in mice that developed β-cell dysfunction and glucose intolerance after treatment with a calcineurin inhibitor that hampered TFEB activation and mitophagy.

The e tTects of Sodium Thiosulfate 00 Metal Toxicity io Wastewater

Sonn Oh,Jungkon Kim,Minjung Lee,Moonho Chung,Kyungho ChOl 한국환경보건학회 2005 한국환경보건학회 학술대회 자료집 Vol.2005 No.-

토양특성 기반 토양수분 함량 예측을 위한 PTF 적용성 검정

허승오(Seung-Oh Hur),손연규(Yeon-Gyu Sonn),현병근(Byung-Kewn Hyun),신국식(Kook-Sik Shin),오택근(Taek-Keun Oh),김정규(Jeong-Gyu Kim) 충남대학교 농업과학연구소 2014 농업과학연구 Vol.41 No.4

Identifying soil water content as a major factor for evaluating irrigation and water resource is a primary module to develop a prediction model. A variety of PTFs (Pedo-Transfer Functions) are applied in the models to estimate soil water content, the analysis techniques, however, which compare the estimated from models and the measured by instruments, are not reached at the level to demonstrate the effectiveness of the PTFs in Korea. Many soil physicians such as Eom, Peterson, Rawls, Saxton, Bruand, Baties, Tomasella & Hodnett (T&H), and Minasny, have developed analytic models using PTFs. Soil data for the analysis used soil water contents on 347 soil series (10 kPa), 358 soil series (33 kPa), 356 soil series (1,500 kPa) established by NAAS (National Academy of Agricultural Science). A coefficient of determination on soil water content at 10, 33 and 1,500 kPa was the highest as 0.5932 in EM (Eom model), 0.6744 in REM (Rawls model) and 0.6108 in REM, respectively. In conclusion, it is strongly suggested that the use of EM or REM is suitable for estimating soil water content in Korea although SM (Saxton model) has been widely used.

Differences in Spatial Variation of Soil Chemistry Between Natural and Anthropogenic Soils

Sonn, Yeon-Kyu,Hur, Seung-Oh,Hyun, Byung-Geun,Cho, Hyun-Joon,Shin, Kook-Sik 한국토양비료학회 2014 한국토양비료학회지 Vol.47 No.6

The Agricultural Land Remodeling Project was launched for agricultural fields with potential risk of flooding which were placed in low-lying area as a part of agricultural sectors of the National 4 River Project. It induced of the reclaimed agricultural fields on a national scale. The arable lands reestablished by reclamation have caused several big problems such as destruction of soil physicochemical properties, and thus the techniques to solve disadvantages were urgently required. In this study, we collected experimental samples from top soils in three agricultural areas, one from conventional agricultural fields (Hwasun, Jeollanam-do) and the others from reclaimed (remodelled) agricultural fields (Naju, Jeollanam-do and Gumi, Gyeongsangbuk-do), The soil chemistry data were analyzed using statistic tools such as semi-variance and kriging, and differences between natural and reconstructed soils were examined. The score, R (Ao) which indicates a dependence distance between each chemical element, was as follows; 21.8~43.5 (Conventional, Hwasoon), 4.4~70.6 (Remodelled, Naju) and 5.3~43.6 (Remodelled, Gumi). These results suggested that chemical properties of the reclaimed agricultural fields had a huge variation. Moreover, the result of kiriging maps also represented a ununiform pattern in the reclaimed lands. As a result of this study, it is strongly required to build up the soil type-specific management techniques for the reclaimed agricultural lands.

Nutrient Balances and Soil Properties Affected by Application of Soybean and Barley Residues

Oh, Taek-Keun,Sonn, Yeon-Kyu,Lee, Dong Sung,Kim, Myung-Sook,Kim, Seok-Cheol,Yun, Hong Bae,Lee, Deog-Bae,Lee, Chang-Hoon Korean Society of Soil Science and Fertilizer 2014 한국토양비료학회지 Vol.47 No.2

An accurate analysis of nutrient balance in different cropping systems is necessary for improving soil fertilities, causing higher crop yields and quality. This study was carried out to investigate the nutrient balance, changes in soil properties, and their effects on crop yield in long-term field cultivation under mono- and rotation-cropping systems (MCS and RCS, respectively). The analytical results of the soil properties showed that the application of mineral fertilizers alone in the MCS leads the reduction of soil CEC, exchangeable Ca, and microbial biomass C and N. Compared with the MCS of soybean, the RCS of soybean and barley significantly improved the soil properties, which increased crop yield. It might be due to the barley residue added to the RCS soil. Mean nutrient balances for 4 years were -55.9 kg N, +34.7 kg $P_2O_5$, and -0.3 kg $K_2O$ $ha^{-1}$ for the MCS and +19.7 kg N, +107.4 kg $P_2O_5$, and -48.6 kg $K_2O$ $ha^{-1}$ for the RCS, respectively. These nutrient imbalances mean that conventional fertilizer recommendations were inadequate for maintaining soil nutrient balance. From these results, we can conclude that the crop rotation may change comprehensive physical, chemical, and biological soil properties. These changes could affect the nutrient balance and then the crop yield.

Nek2 and its substrate, centrobin/Nip2, are required for proper meiotic spindle formation of the mouse oocytes

Sonn, Seongkeun,Oh, Goo Taeg,Rhee, Kunsoo Cambridge University Press 2011 Zygote Vol.19 No.1

<B>Summary</B><P>A typical centrosome consists of a pair of centrioles embedded in a proteinous matrix called pericentriolar material. However, the centrosomes in the mouse oocytes and early embryos lack centrioles, but consist of the γ-tubulin-enriched vesicle aggregates. We previously revealed that Nek2 and centrobin/Nip2, a centrosomal substrate of Nek2, is critical for the mouse early embryogenesis, especially at the step of spindle assembly during mitosis. In order to expand our understanding of the biological functions of Nek2, we examined expression and knockdown phenotypes of Nek2 and its substrates, centrobin and C-Nap1, in the mouse oocyte. Nek2, centrobin and C-Nap1 in the mouse oocytes were also centrosomal. Suppression of Nek2 and its substrates did not affect meiotic resumption of the oocytes. However, meiosis of the <I>Nek2</I>- and <I>centrobin</I>-suppressed oocytes was not completed, but arrested with defects in spindle assembly. No visible phenotype was observed in the <I>C-Nap1</I>-suppressed oocytes. These results indicate that Nek2 is critical for proper assembly of the meiotic spindles. Centrobin may be a possible substrate of Nek2 responsible for the meiotic spindle assembly in the mouse oocytes.</P>

ER-associated CTRP1 regulates mitochondrial fission via interaction with DRP1

Sonn Seong Keun,Seo Seungwoon,Yang Jaemoon,오기숙,Chen Hsiuchen,Chan David C.,이건수,Lee Kyung S.,양영,Oh Goo Taeg 생화학분자생물학회 2021 Experimental and molecular medicine Vol.53 No.-

C1q/TNF-related protein 1 (CTRP1) is a CTRP family member that has collagenous and globular C1q-like domains. The secreted form of CTRP1 is known to be associated with cardiovascular and metabolic diseases, but its cellular roles have not yet been elucidated. Here, we showed that cytosolic CTRP1 localizes to the endoplasmic reticulum (ER) membrane and that knockout or depletion of CTRP1 leads to mitochondrial fission defects, as demonstrated by mitochondrial elongation. Mitochondrial fission events are known to occur through an interaction between mitochondria and the ER, but we do not know whether the ER and/or its associated proteins participate directly in the entire mitochondrial fission event. Interestingly, we herein showed that ablation of CTRP1 suppresses the recruitment of DRP1 to mitochondria and provided evidence suggesting that the ER–mitochondrion interaction is required for the proper regulation of mitochondrial morphology. We further report that CTRP1 inactivation-induced mitochondrial fission defects induce apoptotic resistance and neuronal degeneration, which are also associated with ablation of DRP1. These results demonstrate for the first time that cytosolic CTRP1 is an ER transmembrane protein that acts as a key regulator of mitochondrial fission, providing new insight into the etiology of metabolic and neurodegenerative disorders.

흰쥐 망막의 신경원에서 GABA와 Glycine의 공존

손욱현,오수자,김인범,천명훈,정진웅 대한해부학회 1997 Anatomy & Cell Biology Vol.30 No.6

석회암 유래 토양에서의 물의 이동특성과 토양 입자 및 유기물과의 관계에 따른 Pedo-Transfer Function의 결정

허승오(Seung-Oh Hur),정강호(Kang-Ho Jung),손연규(Yeon-Kyu Sonn),하상건(Sang-Keun Ha),김정규(Jeong-Gyu Kim) 한국토양비료학회 2009 한국토양비료학회지 Vol.42 No.2

강원도 남부(영월)와 충북 제천, 단양 등지에 널리 분포하는 석회암에서 유래된 토양은 점토 및 철분함량이 많은 식질계 토양으로 세립(細粒)질로 구성이되어 있고 자갈이나 잔돌이 있는 토양으로 분류되므로 토양의 침투 및 투수속도가 화강암이나 화강편마암 유래 토양과는 다른 양상을 보인다. 본 연구는 석회암 유래 토양의 침투속도와 토양층위별 투수속도 측정결과인 현장 포화수리전도도(Kfs, field saturationhydraulic conductivity)에 토양의 입도 분포 및 유기물 함량이 미치는 영향을 파악하고자 그들 사이의 상호관계를 분석하였다. 실험을 위해 이용된 토양은 과림, 모산, 장성, 마지,안미, 평안의 6개 토양통이었고 장력 침투계(disctension infiltrometer)와 투수속도 측정계(Guelphpermeameter)로 침투 및 투수속도를 측정하고 입도분포와 유기물함량을 분석했다. 전체 측정대상 토양의 표토 및 층위별 Kfs와 그 토양들의 모래, 미사, 점토 및 유기물 함량과는 유의한 상관관계를 찾을 수없었다. 그것은 측정 토양이 농경지 토양 외에도 산림 토양이 포함되어 있고, 산림토양도 유기물 층이 존재 한다거나 다량의 자갈이나 잔돌 등의 함량이 존재하기 때문인 것으로 여겨진다. 이것은 포화수리 전도도가 토양의 입도분포나 유기물 함량과의 관계가 있다고 했던 다수의 연구와는 상반된 결과이므로 이를 더검토해볼 필요성이 있다. 이를 위해, 측정된 6개의 대상 토양 중에서 암쇄토인 모산통과 유기물 함량이9.2%로 일반토양보다 월등히 높은 과림통의 O충을 제외하고 토양 입도분포 및 유기물 함량과 침투 및 투수속도와의 관계를 살펴보았다. 분석결과 모래의 함량과 Kfs의 관계는 결정계수(R<SUP>2</SUP>)가 0.309로 비교적 낮게 나타나고 있지만 정의 직선 상관관계를 나타냈으며, 미사함량과는 관계가 없었고, 점토함량과는 결정계수가 0.3164로서 부의 직선 상관관계를 나타냈다. 유기물 함량과는 다른 토양 입도분포들보다 결정계수가 높으며(R<SUP>2</SUP>=0.4884<SUP>*</SUP>) 지수함수 관계를 나타내고 있다. 이러한 결과들을 종합하면 석회암 유래토양에서의 현장포화수리 전도도는 모래나 유기물 함량이 많으면 증가하고 점토 함량이 많으면 감소할 것이므로 이들을 조합한다면 현장 포화수리전도도를 예측하는 PTF(Pedo-Transfer Function)를 작성할 수 있다. 본연구에서는 이를 위해 모래, 점토, 유기물 함량을 고려해 PTF를 분석한 결과 점토는 다중 공선성 때문에 제외를 하고 모래와 유기물 함량만을 이용해 Kfs를 예측할 수 있는 PTF를 작성했다. Soils originated from limestone, located at the southern part of Kangwon province and Jecheon, Danyang of Chungbuk province are mainly composed of fine texture, have different properties from soils originated from granite and granite gneiss, especially for water movement. This study was conducted for making PTF(Pedo-Transfer Function) for Kfs(field saturaton hydraulic conductivity) estimation, and for investigating the relation between soil particle distribution and the infiltration and percolation rate in soils originated from limestone. Soils used for the experiment were 6 soils of Gwarim, Mosan, Jangseong, Maji, Anmi and Pyongan series. Infiltration and percolation rate for the soil were measured by a disc tension infiltrometer and a Guelph permeameter, respectively. The particle size distribution and organic matter content of the soils were analyzed. Kfs was not related with sand, silt, clay, and organic mattrer (OM) content because of forest soils which contained high gravel, pebble, and cobble content, and O layer with high OM content. After Mosan soil series and O layer of Gwarim series were excluded for the data analysis, Kfs was explained as a linear function with sand and clay content and a exponential function with OM content. As a result, the PTF equation was obtained as Kfs=-4.20558+0.479706*(S) +0.023187*exp(1.829*OM) (R<SUP>2</SUP>=0.6558<SUP>*</SUP>).

석회암 유래 토양의 침투 및 투수속도 평가에 따른 수문유형 분류

허승오(Seung-Oh Hur),정강호(Kang-Ho Jung),손연규(Yeon-Kyu Sonn),하상건(Sang-Keun Ha),김정규(Jeong-Gyu Kim),김남원(Nam-Won Kim) 한국토양비료학회 2009 한국토양비료학회지 Vol.42 No.2

강원도 남부(영월)와 충북 제천, 단양 등지에 널리분포하는 석회암에서 유래된 토양은 점토 및 철분함량이 많은 식질계 토양이며 pH와 염기포화도(basesaturation)가 높은 붉은색 토양이다. 이 토양은 식양질과 식질 등의 세립(細粒)질로만 구성이 되어 있고자갈이 있는 토양으로 분류된다. 따라서, 토양의 침투및 투수속도가 우리나라 토양의 주 모재인 화강암이나 화강편마암 유래 토양과는 다른 양상을 보인다. 본연구는 세립질 특성을 보이는 석회암 유래 토양의 지표면에서의 침투속도와 토양층위별 투수속도를 측정해 복잡하게 세분되어 있는 토양의 종류를 수문학적 인 목적에 따라 단순화하기 위해 만든 수문학적 토양유형으로 분류하고자 하였다. 실험을 위해 이용된 토양은 과림, 모산, 장성, 마지, 안미, 평안의 6개 토양통이었고 장력 침투계(disctension infiltrometer)와 투수속도 측정계(Guelphpermeameter)로 침투 및 투수속도를 측정했다. 현장측정 이후 토양층위별로 시료를 채취하여 실험실조건에서 입도분포, 유기물함량을 측정했다. 토양통별 침투 및 투수속도를 측정한 결과는 유기물 층이 존재하는 과림통은 공극이 많고 토층 내에 나무 및 식물뿌리가 존재해 전체적으로 침투 및 투수속도가 빠른 특성을 보여 수문유형을 A로 분류하였다. 모산통은 토층 내에 자갈함량이 아주 높고 투수속도가 다른 토양에 비해 월등히 빠른 특성을 나타냈으나 50 cm이내에서 암반층이 존재하는 관계로 수문유형이 B/D로 분류되었다. 토층이 깊지 않은 장성통은 토층 내에 나무 및 식물뿌리가 많고 암석노출지가 존재해 침투속 도가 빠름에도 불구하고 C/D 수문유형으로 분류됐다. 자갈이나 잔돌이 많은 마지통은 잔자갈이 존재하고 침투나 투수속도가 빠른 편으로 B유형이었다. 논으로사용되는 안미통은 다른 석회암 유래토양에 비해 토층이 깊은 편이며 석회암 충적층에서 유래된 토양으로 선상지 및 곡간지에 분포한다. 관개된 상태에서 로타리 작업에 의해 표토의 특성이 교란되는 논으로 이용되는 특성 때문에 침투 및 투수속도는 느려 D유형으로 분류됐다. 잔돌이 존재하는 평안통은 석회암 붕적, 퇴적층으로부터 유래된 토양으로 산록경사지 및 선상단구에 분포하며 표토층인 A층에서 중 입상구조를 보이며 공극이 많고 작물뿌리가 매우 많아 침투속도는 빠르나 B층에서는 점토 함량이 감소했다 증가하면서 토성이 급격히 바뀌는 특성을 나타내 투수속도는 느린 값을 나타내 수문학적 토양유형은 D유형으로 분류됐다. Soils originated from limestone, located at the southern part of Kangwon province and Jecheon, Danyang of Chungbuk province are mainly composed of fine texture, and have different properties from soils originated from granite and granite gneiss, especially for water movement. This study was conducted for classification of hydrologic soil group (HSG) of soils originated from limestone by measuring the infiltration rate of surface soils and percolation rate of sub soils. Soils used for the experiment were 6 soils in total : Gwarim, Mosan, Jangseong, Maji, Anmi and Pyongan series. Infiltration and percolation rate were measured by a disc tension infiltrometer and a Guelph permeameter, respectively. Particle size distribution and organic matter content of the soils were analyzed. HSG, which was made by USDANRCS(National Resources Conservation Service) for hydrology, of Gwarim series with O horizon of accumulated organic matter was classified as type A which show the properties of low runoff potential, rapid infiltration and percolation rate. HSG of Mosan series, which has high gravel content and very rapid permeability, was classified as type B/D because of the impermaeble base rock layer under 50cm from surface. HSG of Jangseong series with shallow soil depth was classified as type C/D owing to the impermaeble base rock layer under 50cm from surface. HSG of Maji series was type B, and HSG of Anmi series used as paddy land was type D because of slow infiltration and percolation rate caused by the disturbance of surface soil by puddling. HSG of Pyeongan series having a sudden change of layer in soil texture was type D because of the slow percolation rate caused a the layer.