Overexpression of Adenine Nucleotide Translocase Induces Apoptosis in Drosophila Cultured Cell

Shin, Myoung-Joo,Park, So-Young,Yoo, Mi-Ac 대한암예방학회 2003 Journal of cancer prevention Vol.8 No.3

Synergic effect of exogenous lactate and caffeine on fat oxidation and hepatic glycogen concentration in resting rats

유충성,김지수,견성환,Takeshi Hashimoto,Hironori Tomi,임기원 한국운동영양학회 2022 Physical Activity and Nutrition (Phys Act Nutr) Vol.26 No.4

[Purpose] Although several physiological roles of lactate have been revealed in the last decades, its effects on energy metabolism and substrate oxidation remain unknown. Therefore, we investigated the effects of lactate on the energy metabolism of resting rats. [Methods] Male rats were divided into control (Con; distilled water), caffeine (Caf; 10 mg/kg), L-lactate (Lac; 2 g/kg), and lactate-plus-caffeine (Lac+Caf; 2 g/ kg + 10 mg) groups. Following oral administration of supplements, resting energy expenditure (study 1), biochemical blood parameters, and mRNA expression involved in energy metabolism in the soleus muscle were measured at different time points within 120 minutes of administration (study 2). Moreover, glycogen level and Pyruvate dehydrogenase (PDH) activity were measured. [Results] Groups did not differ in total energy expenditure throughout the 6 hour post-treatment evaluation. Within the first 4 hours, the Lac and Lac+Caf groups showed higher fat oxidation rates than the Con group (p<0.05). Lactate treatment decreased blood free fatty acid levels (p<0.05) and increased the mRNA expression of fatty acid translocase (FAT/CD36) (p<0.05) and peroxisome proliferator-activated receptor gamma coactivator 1-alpha (PGC-1α) (p<0.05) in the skeletal muscle. Hepatic glycogen level in the Lac+Caf group was significantly increased (p<0.05). Moreover, after 30 and 120 minutes, PDH activity was significantly higher in lactate-supplemented groups compared to Con group (p<0.05). [Conclusion] Our findings showed that Lac+Caf enhanced fat metabolism in the whole body and skeletal muscle while increasing hepatic glycogen concentration and PDH activity. This indicates Lac+Caf can be used as a potential post-workout supplement.

ANT2 suppression by shRNA restores miR-636 expression, thereby downregulating Ras and inhibiting tumorigenesis of hepatocellular carcinoma

김철우,장지영,Young-Sin Lee,전윤경,이경분,장자준 생화학분자생물학회 2013 Experimental and molecular medicine Vol.45 No.1

MicroRNAs (miRNAs) participate in diverse biological functions and carcinogenesis by inhibiting specific gene expression. We previously reported that suppression of adenine nucleotide translocase 2 (ANT2) by using the short hairpin RNA (shRNA)approach has an antitumor effect in several cancer cells. We here examined the influence of ANT2 on expression of miRNAs in hepatocellular carcinoma (HCC) to further elucidate the tumor-suppressive mechanism of ANT2 shRNA. We first carried out screening for miRNAs, whose expression is regulated by ANT2 suppression in the Hep3B HCC cell line using miRNA microarrays. Validation of candidate miRNAs was done by incorporating clinical samples, and their effects on the tumorigenesis of HCC were studied in vitro and in vivo. miR-636 was one of the miRNAs whose expression was highly upregulated by ANT2 suppression in miRNA microarray analysis, as confirmed by real-time reverse transcription-polymerase chain reaction. Notably, miR-636 was markedly downregulated in HCC tissues compared with matched non-neoplastic liver in clinical samples. Restoration of miR-636 in Hep3B cells led to significant reduction of cell proliferation and colony formation. miR-636restoration resulted in a decreased level of Ras, one of the putative targets of miR-636, and inactivation of its signaling pathway. Moreover, tumorigenesis was efficiently suppressed by miR-636 in an in vivo tumor xenograft model of HCC. The data suggest that miR-636 might function as a tumor suppressor miRNA affecting HCC tumorigenesis via downregulation of Ras,and that ANT2 suppression by shRNA could exert an anticancer effect by restoring miR-636 expression in HCC.

B-cell Translocation Gene 2: Expression in the Rat Ovary and Potential Association with Adenine Nucleotide Translocase 2 in Mitochondria

Jae-Il Park,Sang-Young Chun 한국동물생명공학회(구 한국동물번식학회) 2012 발생공학 국제심포지엄 및 학술대회 Vol.2012 No.1

Reverse Warburg Effect-Related Mitochondrial Activity and 18F-FDG Uptake in Invasive Ductal Carcinoma

최병욱,정영주,박성환,오훈규,강성민 대한핵의학회 2019 핵의학 분자영상 Vol.53 No.6

Purpose We evaluated the relationship between fluorine-18 fluoro-2-deoxy-glucose (18F-FDG) uptake and mitochondrial activity in cancer cells and investigated the prognostic implications of this relationship in patients with invasive ductal carcinoma of the breast (IDCB). Methods One hundred forty-six patients with primary IDCB who underwent preoperative 18F-FDG PET/CT followed by curative surgical resection were enrolled in the current study. Mitochondrial activity of cancer cells was assessed based on translocase of outer mitochondrial membrane 20 (TOMM20) expression and cytochrome C oxidase (COX) activity. A Pearson’s correlation analysis was used to assess the relationship between the maximum standardized uptake value of the primary tumour (pSUVmax) and mitochondrial activity. Clinicopathological factors, including pSUVmax, histological grade, oestrogen receptor (ER), progesterone receptor (PR), and TOMM20 expression; and COX activity, were assessed for the prediction of disease-free survival (DFS) using the Kaplan–Meier method and Cox proportional hazards model. Results Fourteen of the 146 subjects (9.6%) showed tumour recurrence. There was a significant positive correlation between 18F-FDG uptake and the mitochondrial activity of cancer cells in patients with IDCB, and increased 18F-FDG uptake and mitochondrial activity were significantly associated with a shorter DFS. Additionally, results from the receiver-operating curve analysis demonstrated that the cut-off values of pSUVmax, TOMM20 expression, and COX activity for the prediction of DFS were 7.76, 4, and 5, respectively. Further, results from the univariate analysis revealed that pSUVmax, TOMM20 expression, PR status, and histologic grade were significantly associated with DFS; however, the multivariate analysis revealed that only pSUVmax was associated with DFS (HR, 6.51; 95% CI, 1.91, 22.20; P = 0.003). Conclusions The assessment of preoperative 18F-FDG uptake and post-surgical mitochondrial activity may be used for the prediction of DFS in patients with IDCB.

A case of glycogen storage disease type Ib

김문선,박재복,기창석,김진경 대한소아청소년과학회 2009 Clinical and Experimental Pediatrics (CEP) Vol.52 No.12

We report a case of an 18-month-old girl with glycogen storage disease type Ib (GSD Ib). Her neutrophil counts had gradually decreased to less than 500/µL by the age of 3 years. However, there were no recurrent bacterial infections. Mutation analysis of the glucose-6-phosphate translocase (G6PT) gene revealed a compound heterozygous missense mutation (Ala148Val/Gly273Asp).

B-cell translocation gene 2: Expression in the rat ovary and potential association with adenine nucleotide translocase 2 in mitochondria

Park, J.I.,Kim, S.G.,Baek, M.W.,Park, T.J.,Lim, I.K.,Seo, Y.W.,Chun, S.Y. North-Holland 2013 Molecular and cellular endocrinology Vol.367 No.1

The B-cell translocation gene 2 (Btg2) is an anti-proliferative tumor suppressor gene that behaves as a transcriptional regulator. The present study investigated gonadotropin induction of Btg2 in the rat ovary and the mechanism of Btg2 action as a partner of mitochondrial protein adenine nucleotide translocase 2 (Ant2). Transient induction of Btg2 as well as Btg1 mRNA levels by LH/hCG was observed in ovarian granulosa cells. Btg2 protein levels were also stimulated by LH/hCG. LH-induced gene expression of Btg2 required ERK signal pathway. Studies of deletion mutants in HeLa cells showed that deletion of Btg2 C-terminus (Btg2/ΔC) abolished the interaction with Ant2. In fact, the expression levels of Btg2/ΔC construct were decreased in mitochondrial fraction. Btg2 was also expressed in mitochondria and interacted with Ant2 in preovulatory granulosa cells. Interestingly, a Btg2/ΔC construct inhibited an action of Btg2 wild-type on ATP and H<SUB>2</SUB>O<SUB>2</SUB> production. These findings demonstrate the gonadotropin stimulation of Btg2 in the ovary and, the physical interaction of Btg2 with Ant2 in mitochondria.

In silico analysis and experimental validation of lipoprotein and novel Tat signal peptides processing in Anabaena sp. PCC7120

Sonika Kumari,CHAURASIAAKHILESH KUMAR 한국미생물학회 2015 The journal of microbiology Vol.53 No.12

Signal peptide (SP) plays a pivotal role in protein translocation. Lipoprotein- and twin arginine translocase (Tat) dependent signal peptides were studied in All3087, a homolog of competence protein of Synechocystis PCC6803 and in two putative alkaline phosphatases (ALPs, Alr2234 and Alr4976), respectively. In silico analysis of All3087 is shown to possess the characteristics feature of competence proteins such as helix-hairpin-helix, N and C-terminal HKD endonuclease domain, calcium binding domain and N-terminal lipoprotein signal peptide. The SP recognition-cleavage site in All3087 was predicted (AIA-AC) using SignalP while further in-depth analysis using Pred-Lipo and WebLogo analysis for consensus sequence showed it as IAA-C. Activities of putative ALPs were confirmed by heterologous overexpression, activity assessment and zymogram analysis. ALP activity in Anabaena remains cell bound in log-phase, but during late log/stationary phase, an enhanced ALP activity was detected in extracellular milieu. The enhancement of ALP activity during stationary phase was not only due to inorganic phosphate limitation but also contributed by the presence of novel bipartite Tat-SP. The Tat signal transported the folded active ALPs to the membrane, followed by anchoring into the membrane and successive cleavage enabling transportation of the ALPs to the extracellular milieu, because of bipartite architecture and processing of transit Tat-SP.

Lipid flippase modulates olfactory receptor expression and odorant sensitivity in <i>Drosophila</i>

Ha, Tal Soo,Xia, Ruohan,Zhang, Haiying,Jin, Xin,Smith, Dean P. National Academy of Sciences 2014 PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF Vol.111 No.21

<P>In <I>Drosophila melanogaster</I>, the male-specific pheromone cVA (11-<I>cis</I>-vaccenyl acetate) functions as a sex-specific social cue. However, our understanding of the molecular mechanisms underlying cVA pheromone transduction and its regulation are incomplete. Using a genetic screen combined with an electrophysiological assay to monitor pheromone-evoked activity in the cVA-sensing Or67d neurons, we identified an olfactory sensitivity factor encoded by the <I>dATP8B</I> gene, the <I>Drosophila</I> homolog of mammalian ATP8B. dATP8B is expressed in all olfactory neurons that express Orco, the odorant receptor coreceptor, and the odorant responses in most Orco-expressing neurons are reduced. Or67d neurons are severely affected, with strongly impaired cVA-induced responses and lacking spontaneous spiking in the mutants. The <I>dATP8B</I> locus encodes a member of the P4-type ATPase family thought to flip aminophospholipids such as phosphatidylserine and phosphatidylethanolamine from one membrane leaflet to the other. dATP8B protein is concentrated in the cilia of olfactory neuron dendrites, the site of odorant transduction. Focusing on Or67d neuron function, we show that Or67d receptors are mislocalized in <I>dATP8B</I> mutants and that cVA responses can be restored to <I>dATP8B</I> mutants by misexpressing a wild-type <I>dATP8B</I> rescuing transgene, by expressing a vertebrate P4-type ATPase member in the pheromone-sensing neurons or by overexpressing Or67d receptor subunits. These findings reveal an unexpected role for lipid translocation in olfactory receptor expression and sensitivity to volatile odorants.</P>

Streptomyces lividans TK24에서 secY homolog의 클로닝과 분석

김순옥,서주원 한국산업미생물학회 1998 한국미생물·생명공학회지 Vol.26 No.2

몇가지 그람양성 세균에서 secY 유전자가 함유된 operon의 구성이 rplO(L15)-secY-adk라는 결과를 토대로 L15와 adk 유전자일부를 primer로 제작하여 Streplomyces lividans TK24에서 secY 유전자가 함유된 1.8kb 단편을 PCR로 증폭하여 얻은 후 secY 유전자를 cloning하였다. 전 단편을 sequencing하여 추론한 아미노산으로 상동성을 조사해 본 결과 Escherichia coli, Bacillus subtilis, Micrococcus luteus, Bacillus licheniformis, Staphylococcus carnosus, Brevibacterium flavum, Streptomyces scabies의 SecY와 각각 46%, 43%, 57%, 44%, 42%, 56%, 90%의 유사성을 보이는 것으로 나타났으며 SecY의 소수성 profile 또한 서로 유사하고 10개의 membrane spanning segment를 동일하게 가지는 것으로 나타났다. 유전자 구조도 다른 그람양성균에서와 같이 L15-SecY-Adk 순 이였으며 secY 유전자의 종결코돈과 adk 유전자의 개시코돈이 한 염기를 공유하는 상태의 translational coupling 구조를 하고 있었다. 이와같이 단백질분비에 관여하는 유전자와 ribosome 구성요소, 그리고 ATP 합성에 관여하는 요소는 세포성장에 상호 연관 작용이 있는 것으로 사료된다. The secY gene of Streptomyces lividans TK24 was cloned by the PCR method with synthetic oligonucleotide primers designed on the basis of the conserved regions of L15-secY-adk operon from E. coli, B. subtilis, and M. luteus. The deduced amino acid sequences of the SecY are highly homologous to those of other known SecY. It has 46%, 43%, 57%, 44%, 42%, 56%, 90% similarity to Escherichia coli, Bacillus subtilis, Micrococcus luteus, Bacillus licheniformis, Staphylococcus carnosus, Brevibacterium flavum, Streptomyces scabies, respectively and almost the same with Streptomyces coelicolor. The gene organization of L15-SecY-Adk is also similar to those of other bacteria. SecY and Adk are very likely translationally coupled that is overlapping stop codon of SecY and start codon of Adk with one base pair, which is common structure among high GC content strains of gram positive bacteria.