Effects of Ar/O2 Gas Ratio on ZnO Films Prepared by Using Ion Beam Deposition

Lee, InHwan,Kim, Myoung,Jeon, Ju-Won,Jeon, Dae-Woo,Sahoo, Trilochan,Lee, Mi-Hee,Lee, Ru-Da,Jang, Lee-Woon,Ju, Jin-Woo,Jo, Young Je,Kwak, Joon Seop Korean Physical Society 2010 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.57 No.6

In vivo Import Experiments in Protoplasts Reveal the Importance of the Overall Context but Not Specific

Inhwan Hwang,Kwang Hee Lee,Dae Heon Kim,Sang Woo Lee,Zhoo Hyeon Kim 한국분자세포생물학회 2002 Molecules and cells Vol.14 No.3

Functional characterization of sequence motifs in the transit peptide of Arabidopsis small subunit of rubisco.

Lee, Dong Wook,Lee, Sookjin,Lee, Gil-Je,Lee, Kwang Hee,Kim, Sanguk,Cheong, Gang-Won,Hwang, Inhwan American Society of Plant Physiologists 2006 PLANT PHYSIOLOGY - Vol.140 No.2

<P>The transit peptides of nuclear-encoded chloroplast proteins are necessary and sufficient for targeting and import of proteins into chloroplasts. However, the sequence information encoded by transit peptides is not fully understood. In this study, we investigated sequence motifs in the transit peptide of the small subunit of the Rubisco complex by examining the ability of various mutant transit peptides to target green fluorescent protein reporter proteins to chloroplasts in Arabidopsis (Arabidopsis thaliana) leaf protoplasts. We divided the transit peptide into eight blocks (T1 through T8), each consisting of eight or 10 amino acids, and generated mutants that had alanine (Ala) substitutions or deletions, of one or two T blocks in the transit peptide. In addition, we generated mutants that had the original sequence partially restored in single- or double-T-block Ala (A) substitution mutants. Analysis of chloroplast import of these mutants revealed several interesting observations. Single-T-block mutations did not noticeably affect targeting efficiency, except in T1 and T4 mutations. However, double-T mutants, T2A/T4A, T3A/T6A, T3A/T7A, T4A/T6A, and T4A/T7A, caused a 50% to 100% loss in targeting ability. T3A/T6A and T4A/T6A mutants produced only precursor proteins, whereas T2A/T4A and T4A/T7A mutants produced only a 37-kD protein. Detailed analyses revealed that sequence motifs ML in T1, LKSSA in T3, FP and RK in T4, CMQVW in T6, and KKFET in T7 play important roles in chloroplast targeting. In T1, the hydrophobicity of ML is important for targeting. LKSSA in T3 is functionally equivalent to CMQVW in T6 and KKFET in T7. Furthermore, subcellular fractionation revealed that Ala substitution in T1, T3, and T6 produced soluble precursors, whereas Ala substitution in T4 and T7 produced intermediates that were tightly associated with membranes. These results demonstrate that the transit peptide contains multiple motifs and that some of them act in concert or synergistically.</P>

왕느릅나무 껍질 열수 추출물의 마우스에서의 in vivo 면역조절 효과

이인환(Inhwan Lee),권다혜(Da Hye Kwon),이선희(Sun Hee Lee),이성도(Sung Do Lee),김덕원(Deok Won Kim),이종환(Jong-Hwan Lee),현숙경(Sook Kyung Hyun),김철민(CheolMin Kim),김병우(Byoung Woo Kim),강경화(Kyung-Hwa Kang),황혜진(Hye Jin Hwang 한국생명과학회 2014 생명과학회지 Vol.24 No.10

약용식물은 염증, 감염증, 암과 같은 질병에 광범위하게 사용되고 있으며, 전통적으로 오래 동안 사용되어 왔다. 왕느릅나무(Ulmus macrocarpa Hance)는 느릅나무의 한 종으로서 중국, 일본을 비롯해 한국 전역에 분포하고 있으며, 줄기와 뿌리의 껍질을 유백피라 하여 한의학에서 피부염, 유방염, 부종 등에 사용하여 왔다. 이 연구의 목적은 유백피의 열수 추출물(Ulmus cortex water extract, UCWE)이 면역조절 기능을 가지고 있는지를 조사하는 것이다. UCWE 식이농도 30 mg/kg, 100 mg/kg, 300 mg/kg의 3개 군으로 나누어 14일 동안 식이한 후 면역반응을 측정하였다. IL-2, IL-12, IFN-γ 의 혈중 농도가 UCWE를 식이한 군에서 유의적으로 증가하였으며, lymphokine activated killer cells (LAK)을 이용한 세포매개 세포독성 시험에서도 정상군에 비해 UCWE를 식이한 군에서 유의적으로 증가하였다. 그러나, 간, 신장, 비장, 흉선의 무게변화는 UCWE를 식이한 군과 정상군과의 차이가 없었다. 이는 300 ㎎/㎏ 고농도의 2주간 식이가 장기에 영향을 거의 미치지 않는다는 것을 암시한다고 생각된다. 따라서, UCWE는 내부 장기에는 영향을 주지 않으며 면역기능을 향상시키는 효과를 가진다고 여겨진다. Traditional medicinal plants are widely used to treat many diseases, such as inflammation, infections, and even cancer. Ulmus macrocarpa Hance, a Chinese elm species, is distributed in Korea, China, and Japan. The stem bark is widely employed in Korean traditional medicine to treat dermatitis, mastitis, and edema. The aim of this study was to investigate whether water extract of U. macrocarpa Hance bark (Ulmus cortex) has a immune-modulating function in a mouse model. Three different concentrations (30 ㎎/㎏, 100 mg/kg, and 300 ㎎/㎏) of Ulmus cortex water extract (UCWE) were orally administered to mice for 14 days, and their immune responses were analyzed. Cytokines, such as interleukin (IL)-2, IL-12, and IFN-γ, increased in the blood of UCWE-fed groups when compared with a control group. In contrast, the IL-4 level did not change in any of the UCWE-fed groups Cell-mediated cytotoxicity was also assayed using lymphokine-activated killer cells (LAK). LAK showed greater cytotoxicity in the UCWE-fed groups than LAK in the control group. Internal organ indices, such as liver, kidney, spleen, and thymus, were similar in all the groups, including the control group, indicating that UCWE may have been nontoxic in the experimental animals. These data suggest that UCWE has an immune-modulating function in a mouse model.

3D reconstruction of as-built model of plant piping system from point clouds and port information

Inhwan Dennis Lee,Ikjin Lee,Soonhung Han 한국CDE학회 2021 Journal of computational design and engineering Vol.8 No.1

This paper proposes a reconstruction method of the as-built model of plant piping, where the port point of the fitting is used as the secondary reference point, which represents a connection point between the fitting and its connected pipeline. The connection point between a fitting and a pipeline is a critical point of reference in the as-built model. In this study, a fitting model is registered to the point clouds first by using the state-of-the-art technique, which is based on an iterative closest point (ICP) algorithm and also considers the alignment of the port direction with the connected pipelines. Then, the port points of the registered fitting are considered as connection points, and the nozzle points of the connected pipelines are adjusted along its axis based on the information. After the registration process, which uses the detailed shape of fitting and the directions of adjacent pipelines at the same time, the port point on the registered fitting becomes a better estimate of the connection point compared with the nozzle point of a pipeline detected.

OPEN ACCESS : Association of sarcopenia and physical activity with femur bone mineral density in elderly women

( Inhwan Lee ),( Changduk Ha ),( Hyunsik Kang ) 한국운동영양학회 2016 Physical Activity and Nutrition (Phys Act Nutr) Vol.20 No.1

[Purpose] This study examined the association of femur bone mineral density (BMD) with body composition and physical activity in elderly women. [Methods] This was a cross sectional study involving 119 women with mean age of 73.1±5.5 years. Body composition parameters including body mass index (BMI), percent of body fat (%BF), appendicular skeletal muscle mass (ASM) index and femur BMD was measured by dual-energy X-ray absorptiometry (DXA). Physical activity was assessed by the uniaxial accelerometer for 7 consecutive days including weekends. Based on femur BMD T-scores, subjects were classified as optimal group, osteopenia group, and osteoporosis group. Based on ASM index, subjects were classified as normal group and sarcopenia group. According to WHO recommendations of physical activity for elderly, the subjects were classified as active group or inactive group. Logistic regression analyses were used to determine the odds ratio (OR) for osteopenia and osteoporosis. [Results] There were linear decreases for body composition parameters including weight (P=.023), BMI (P=.039), lean mass (P=.032), ASM index (P=.007) and physical activity parameters including daily of step (P<.001), low intensity physical activity (P<.001), moderate intensity physical activity (P=.001) across femur BMD levels. Compared to the normal group (OR=1), the sarcopenia group had a significantly higher OR (OR=4.823; P=.042), and the inactive group had a significantly higher OR (OR=5.478; P=.005) having osteopenia and osteoporosis when compared to the active group (OR=1). [Conclusion] The findings of this study suggested that physical activity along with a healthy nutrition should be promoted as a preventive strategy against osteopenia and osteoporosis in elderly women.

Sorting of nuclear-encoded chloroplast membrane proteins

Lee, Dong Wook,Lee, Junho,Hwang, Inhwan Elsevier 2017 Current opinion in plant biology Vol.40 No.-

<P>Among the many organelles in eukaryotic cells, chloroplasts have the most complex structure, with multiple suborganellar membranes, making protein targeting to chloroplasts, particularly to various suborganellar membranes, highly challenging. Multiple mechanisms function in the biogenesis of chloroplast membrane proteins. Nuclear-encoded nascent proteins can be targeted to the outer envelope membrane directly from the cytosol after translation, but their targeting to the inner envelope and thylakoid membranes requires multiple steps, including cytosolic sorting, translocation across the envelope membranes, sorting in the stroma, and insertion into their target membranes. In this review, we discuss the current knowledge about the sorting mechanisms of proteins to the two envelope membranes and the thylakoid membrane, along with perspectives for future research.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Chloroplasts have three membranes, outer/inner envelopes and thylakoid membranes. </LI> <LI> AKR2 coordinates cytosolic sorting and insertion of proteins into outer envelope. </LI> <LI> Two pathways operate for biogenesis of inner envelope proteins. </LI> <LI> The cpSRP pathway plays a key role in biogenesis of LHCPs into thylakoid membranes. </LI> <LI> Besides LHCPs, most thylakoid membrane proteins are inserted spontaneously. </LI> </UL> </P>

Disruption of glycosylphosphatidylinositol-anchored lipid transfer protein gene altered cuticular lipid composition, increased plastoglobules, and enhanced susceptibility to infection by the fungal pathogen Alternaria brassicicola.

Lee, Saet Buyl,Go, Young Sam,Bae, Hyun-Jong,Park, Jong Ho,Cho, Sung Ho,Cho, Hong Joo,Lee, Dong Sook,Park, Ohkmae K,Hwang, Inhwan,Suh, Mi Chung American Society of Plant Physiologists 2009 PLANT PHYSIOLOGY - Vol.150 No.1

<P>All aerial parts of vascular plants are covered with cuticular waxes, which are synthesized by extensive export of intracellular lipids from epidermal cells to the surface. Although it has been suggested that plant lipid transfer proteins (LTPs) are involved in cuticular lipid transport, the in planta evidence is still not clear. In this study, a glycosylphosphatidylinositol-anchored LTP (LTPG1) showing higher expression in epidermal peels of stems than in stems was identified from an Arabidopsis (Arabidopsis thaliana) genome-wide microarray analysis. The expression of LTPG1 was observed in various tissues, including the epidermis, stem cortex, vascular bundles, mesophyll cells, root tips, pollen, and early-developing seeds. LTPG1 was found to be localized in the plasma membrane. Disruption of the LTPG1 gene caused alterations of cuticular lipid composition, but no significant changes on total wax and cutin monomer loads were seen. The largest reduction (10 mass %) in the ltpg1 mutant was observed in the C29 alkane, which is the major component of cuticular waxes in the stems and siliques. The reduced content was overcome by increases of the C29 secondary alcohols and C29 ketone wax loads. The ultrastructure analysis of ltpg1 showed a more diffuse cuticular layer structure, protrusions of the cytoplasm into the vacuole in the epidermis, and an increase of plastoglobules in the stem cortex and leaf mesophyll cells. Furthermore, the ltpg1 mutant was more susceptible to infection by the fungus Alternaria brassicicola than the wild type. Taken together, these results indicated that LTPG1 contributed either directly or indirectly to cuticular lipid accumulation.</P>

Phosphatidylinositol 4,5-bisphosphate is important for stomatal opening

Lee, Yuree,Kim, Yong-Woo,Jeon, Byeon Wook,Park, Ki-Youb,Suh, Su Jeoung,Seo, Jiyoung,Kwak, June M.,Martinoia, Enrico,Hwang, Inhwan,Lee, Youngsook Blackwell Scientific Publishers and BIOS Scientifi 2007 The Plant journal Vol.52 No.5

<P>Summary</P><P>Previously, we demonstrated that a protein that binds phosphatidylinositol 4,5-bisphosphate [PtdIns(4,5)P<SUB>2</SUB>] inhibits both light-induced stomatal opening and ABA-induced stomatal closing. The latter effect is due to a reduction in free PtdIns(4,5)P<SUB>2</SUB>, decreasing production of inositol 1,4,5-trisphosphate and phosphatidic acid by phospholipases C and D. However, it is less clear how PtdIns(4,5)P<SUB>2</SUB> modulates stomatal opening. We found that in response to white light irradiation, the PtdIns(4,5)P<SUB>2</SUB>-binding domain GFP:PLC&dgr;1PH translocated from the cytosol into the plasma membrane. This suggests that the level of PtdIns(4,5)P<SUB>2</SUB> increases at the plasma membrane upon illumination. Exogenously administered PtdIns(4,5)P<SUB>2</SUB> substituted for light stimuli, inducing stomatal opening and swelling of guard cell protoplasts. To identify PtdIns(4,5)P<SUB>2</SUB> targets we performed patch-clamp experiments, and found that anion channel activity was inhibited by PtdIns(4,5)P<SUB>2</SUB>. Genetic analyses using an Arabidopsis <I>PIP5K4</I> mutant further supported the role of PtdIns(4,5)P<SUB>2</SUB> in stomatal opening. The reduced stomatal opening movements exhibited by a mutant of Arabidopsis <I>PIP5K4</I> (<I>At3g56960</I>) was countered by exogenous application of PtdIns(4,5)P<SUB>2</SUB>. The phenotype of reduced stomatal opening in the <I>pip5k4</I> mutant was recovered in lines complemented with the full-length <I>PIP5K4</I>. Together, these data suggest that PIP5K4 produces PtdIns(4,5)P<SUB>2</SUB> in irradiated guard cells, inhibiting anion channels to allow full stomatal opening.</P>

LINEAR ISOMORPHISMS OF NON-DEGENERATE INTEGRAL TERNARY CUBIC FORMS

Lee, Inhwan,Oh, Byeong-Kweon Korean Mathematical Society 2016 대한수학회보 Vol.53 No.6

In this article, we consider the problem on finding non-degenerate nary m-ic forms having an $n{\times}n$ matrix A as a linear isomorphism. We show that it is equivalent to solve a linear diophantine equation. In particular, we find all integral ternary cubic forms having A as a linear isomorphism, for any $A{\in}GL_3({\mathbb{Z}})$. We also give a family of non-degenerate cubic forms F such that F(x) = N always has infinitely many integer solutions if exists.