• BMB Reports
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• 제41권2호
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• pp.153-157
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• 2008

The objective of the present study was to identify mitochondrial components associated with the damage caused by iron to the rat heart. Decreased cell viability was assessed by increased presence of lactate dehydrogenase (LDH) in serum. To assess the functional integrity of mitochondria, Reactive Oxygen Species (ROS), the Respiratory Control Ratio (RCR), ATP and chelatable iron content were measured in the heart. Chelatable iron increased 15-fold in the mitochondria and ROS increased by 59%. Deterioration of mitochondrial function in the presence of iron was demonstrated by low RCR (46% decrease) and low ATP content (96% decrease). Using two dimensional gel electrophoresis (2DE), we identified alterations in 21 mitochondrial proteins triggered by iron overload. Significantly, expression of the $\alpha$, $\beta$, and d subunits of $F_1F_o$ ATP synthase increased along with the loss of ATP. This suggests that the $F_1F_o$ ATP synthase participates in iron metabolism.

• 한국자기공명학회논문지
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• 제17권2호
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• pp.67-75
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• 2013

ATP synthase produces ATP, a major energy source for metabolic processes in organisms, from ADP and inorganic phosphate in cellular membranes. ATP synthase is known as a rotary motor, in which the c-subunit ring functions as a rotor. In this work, we have tried to develop a more general preparation procedure of thermophilic $F_oc$-ring ($TF_oc$-ring) for NMR measurements. The expression of $TF_oF_1$ is easily affected by various experimental conditions such as temperature, shape and size of a flask, a volume of medium, and shaking rate of an incubator. Accordingly, we have tried to optimize the expression conditions of $TF_oF_1$. $TF_oc$-rings were purified from $TF_oF_1$ according to a reported method. We modified purification procedures to improve purity and yield of $TF_oc$. On top of them, we found a new combination of detergents for the purification at anion-exchange column chromatography. To examine the effect of lipid environments on the structure, the $TF_oc$-rings were reconstituted into two kinds of lipid bilayers, namely, saturated and unsaturated lipid ones. Then, we have compared characteristics of the $TF_oc$-ring structures in these membranes with solid-state NMR.

• Molecules and Cells
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• 제23권3호
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• pp.363-369
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• 2007

Mitochondria play a central role in energy-generating processes and may be involved in the regulation of channels and receptors. Here we investigated TRPM7, an ion channel and functional kinase, and its regulation by mitochondria. Proton ionophores such as CCCP elicited a rapid decrease in outward TRPM7 whole-cell currents but a slight increase in inward currents with pipette solutions containing no MgATP. With pipette solutions containing 3 mM MgATP, however, CCCP increased both outward and inward TRPM7 currents. This effect was reproducible and fully reversible, and repeated application of CCCP yielded similar decreases in current amplitude. Oligomycin, an inhibitor of $F_1/F_O$-ATP synthase, inhibited outward whole-cell currents but did not affect inward currents. The respiratory chain complex I inhibitor, rotenone, and complex III inhibitor, antimycin A, were without effect as were kaempferol, an activator of the mitochondrial $Ca^{2+}$ uniporter, and ruthenium red, an inhibitor of the mitochondrial $Ca^{2+}$ uniporter. These results suggest that the inner membrane potential (as regulated by proton ionophores) and the $F_1/F_O$-ATP synthase of mitochondria are important in regulating TRPM7 channels.

• Journal of Ginseng Research
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• 제19권2호
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• pp.127-133
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• 1995

The complete open reading frame (ORF) of o-subunit of the $F_1$ ATP synthase (atPA) in Korean ginseng mitochondria was identified by the sequence similarity with atPA genes in other plant mitochondria. The sequence alignment showed that the common translation initiation codon, ATG, in plant genes was replaced with GTG valid codon in Korean ginseng. The atPA gene from GTG to TGA termination codon was 1524 nucleotides long, and the sequence homology of nucleotides and deduced amino acids revealed high values of 92~97%. A deletion event of 6 nucleotides was observed at the 1468th nucleotide from the GTG in Korean ginseng, in contrast to that at the 1450th in other plants such as pea, common bean, soybean, sugar beet, and radish. An unidentified open reading frame (on7) was observed upstream of atmA ORF. No other ATG as an initiation codon was detected in the region between off and atmA ORF in Korean ginseng, although a pyrimidine cluster "TTTTCTTTT" was located in this region as in Oenothera and maize genes. It could be supposed that GTG codon in atpA gene of Korean ginseng mitochondria would act as an initiation codon as in microbial genes.ial genes.

• 한국작물학회지
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• 제65권2호
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• pp.113-123
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• 2020

본 논문은 과산화수소 엽면 처리를 통해 수수에서 한발 스트레스 완화 효과가 있는지 알아보기 위하여 과산화수소 처리에 따른 생육 및 생리적 특성 변화와 단백질 변화를 분석하였다. 1. 포장 실험에서 한발 스트레스는 수수 생장을 감소시켰으나, 과산화수소 처리구에서는 과산화수소 무처리구보다 생육이 우수하였다. 또한 한발 조건에서 과산화수소 처리는 무처리에 비해 수량 관련 형질들의저하를 막는 효과를 보였다. 2. 엽 녹색도(SPAD) 및 엽록소 형광(Fv/Fm), 광합성 형질 조사에서 과산화수소 처리가 과산화수소 무처리보다 높았고, 포장 실험에서 엽내 과산화수소 함량은 적습+H₂O₂ 처리가 적습+H₂O 처리보다 과산화수소 함량이 227.8 µmol·g^-1 높았고, 한발 조건에서 엽내 과산화수소 함량은 한발+H₂O₂ 처리가 한발+H₂O 처리보다 16.7 µmol·g^-1으로 낮았다. 3. 한발 조건에서 과산화수소 처리는 여러 단백질의 발현을 변화시켰으며, 특히 광합성 관련 단백질인 ATP synthase deltal chain, cytochrome b6-f complex iron-sulfur subunit, ATP synthase subunit gamma, putative uncharacterized protein Sb02g002690, Sb07g027500와 Superoxide 라디칼을 제거해주는 superoxide dismutase가 증가한 것을 확인하였다. 그리고 단백질 보호와 복원에 관련된 heat shock protein의 발현 증가도 확인되었다. 종합적으로 과산화수소 엽면 처리가 한발 하에서 광합성 관련 단백질의 발현을 증가와 기공 개도를 높여 광합성 능력을 향상시켰다. 특히 엽내에 축적될 수 있는 활성산소종을 제거하는 항산화 능력이 높아져 한발 스트레스 대한 내성을 높여 수수의 생육과 수량성 저하가 억제되는 것을 확인할 수 있었다.