A Prediction Model for Human Immunodeficiency Virus Infection and Mother-to-Child Transmission Based on the Expression Levels of Selenoprotein Genes / 中国医学科学院学报

Objective To study the expression of selenoprotein genes in human immunodeficiency virus(HIV)infection and its mother-to-child transmission,so as to provide a theoretical basis for the prevention,diagnosis,and treatment of acquired immunodeficiency syndrome.Methods The dataset GSE4124 was downloaded from the Gene Expression Omnibus(GEO).Two groups of HIV-positive mothers(n=25)and HIV-negative mothers(n=20)were designed.HIV-positive mothers included a subset of transmitter(TR)mothers(n=11)and non-transmitter(NTR)mothers(n=14).Then,t-test was carried out to compare the expression levels of selenoprotein genes between the four groups(HIV-positive vs. HIV-negative,NTR vs. HIV-negative,TR vs. HIV-negative,TR vs. NTR).Univariate and multivariate Logistic regression were adopted to analyze the effects of differentially expressed genes on HIV infection and mother-to-child transmission.R software was used to establish a nomogram prediction model and evaluate the model performance.Results Compared with the HIV-negative group,HIV-positive,NTR,and TR groups had 8,5 and 8 down-regulated selenoprotein genes,respectively.Compared with the NTR group,the TR group had 4 down-regulated selenoprotein genes.Univariate Logistic regression analysis showed that abnormally high expression of GPX1,GPX3,GPX4,TXNRD1,TXNRD3,and SEPHS2 affected HIV infection and had no effect on mother-to-child transmission.The multivariate Logistic regression analysis showed that the abnormally high expression of TXNRD3(OR=0.032,95%CI=0.002-0.607,P=0.022)was positively correlated with HIV infection.As for the nomogram prediction model,the area under the receiver-operating characteristic curve for 1-year survival of HIV-infected patients was 0.840(95%CI=0.690-1.000),and that for 3-year survival of HIV-infected patients was 0.870(95%CI=0.730-1.000).Conclusions Multiple selenoprotein genes with down-regulated expression levels were involved in the regulation of HIV infection and mother-to-child transmission.The abnormal high expression of TXNRD3 was positively correlated with HIV infection.The findings provide new ideas for the prevention,diagnosis,and treatment of acquired immunodeficiency syndrome.

Role of selenoprotein M knockdown in the melatonin antagonism of nickel-induced apoptosis and endoplasmic reticulum stress in mouse heart / 浙江大学学报（英文版）（B辑：生物医学和生物技术）

The aim of this study was to investigate the role of selenoprotein M (SelM) in endoplasmic reticulum stress and apoptosis in nickel-exposed mouse hearts and to explore the detoxifying effects of melatonin. At 21 d after intraperitoneal injection of nickel chloride (NiCl2) and/or melatonin into male wild-type (WT) and SelM knockout (KO) C57BL/6J mice, NiCl2 was found to induce changes in the microstructure and ultrastructure of the hearts of both WT and SelM KO mice, which were caused by oxidative stress, endoplasmic reticulum stress, and apoptosis, as evidenced by decreases in malondialdehyde (MDA) content and total antioxidant capacity (T-AOC) activity. Changes in the messenger RNA (mRNA) and protein expression of genes related to endoplasmic reticulum stress (activating transcription factor 4 (ATF4), inositol-requiring protein 1 (IRE1), c-Jun N-terminal kinase (JNK), and C/EBP homologous protein (CHOP)) and apoptosis (B-cell lymphoma-2 (Bcl-2), Bcl-2-associated X protein (Bax), Caspase-3, Caspase-9, and Caspase-12) were also observed. Notably, the observed damage was worse in SelM KO mice. Furthermore, melatonin alleviated the heart injury caused by NiCl2 in WT mice but could not exert a good protective effect in the heart of SelM KO mice. Overall, the findings suggested that the antioxidant capacity of SelM, as well as its modulation of endoplasmic reticulum stress and apoptosis, plays important roles in nickel-induced heart injury.

Thyroid hormone metabolism defect caused by SECISBP2 gene mutation: a case report and literatures review / 中华内分泌代谢杂志

We reported the first case of a boy with selenocysteine insertion sequence binding protein 2 (SECISBP2) compound heterozygous mutation in China and provide a review of literatures to improve clinicians′ understanding of the thyroid hormone metabolism defect. Clinically, for children with growth retardation and delayed motor development, thyroid hormone metabolism deficiency should be considered if the thyroid function test shows normal or slightly elevated TSH, elevated T 4 and decreased T 3.

The relieving effect of sun-dried protein tonic on sports fatigue / O efeito calmante na fadiga esportiva da proteína tônica secada ao sol / El efecto calmante en la fatiga deportiva de la proteína tónica secada al sol

ABSTRACT Fatigue is a comprehensive process that involves many physiological and biochemical factors. It is a normal physiological reaction when human physical or mental activities reach a certain level. In recent years, it has been verified that free radicals are closely related to exercise-induced fatigue. Cardamine bursa purified selenoprotein has good oxygen-free radical scavenging ability and anti-lipid peroxide. It could protect mitochondria, liver, and red blood cells from peroxide injury. Therefore, it was speculated that the purification of selenoprotein Cardamine may play an active role in attenuating exercise-induced fatigue by scavenging free radicals. This study cleared the selenite protein Capsella bursa (SPC) as a research object, and evaluated its structural characteristics in relieving exercise-induced fatigue. The selenoprotein index system for exercise-induced fatigue was constructed by combining two AHP methods, principal component analysis and factor analysis. Purity, subunit composition, amino acid composition and RCM content were evaluated. The corresponding RCM protein was preliminarily predicted. The results showed that SPCH could significantly prolong the swimming time (P <0.01), improve the lactate clearance capacity (P <0.01), increase the glycogen content of the liver (P <0.01), and reduce the level of the BUN (P <0.05). SPCH has a good effect in relieving exercise-induced fatigue in mice, so it can be considered for development as a nutritional supplement to alleviate exercise-induced fatigue.

RESUMO Fadiga é um processo abrangente envolvendo muitos fatores fisiológicos e bioquímicos. É uma reação fisiológica normal quando as atividades físicas ou mentais humanas atingem um certo nível. Nos últimos anos, verificou-se que os radicais livres estão intimamente relacionados com a fadiga induzida pelo exercício. A selenoproteina purificada de Cardamina bursa tem boa capacidade de depuração de radicais sem oxigénio e de peróxido anti-lípido. Poderia proteger as mitocôndrias, fígado e glóbulos vermelhos de lesões por peróxido. Por conseguinte, especulou-se que a purificação da selenoproteina de Cardamina pode desempenhar um papel activo na atenuação da fadiga induzida pelo exercício por meio de radicais livres de scavenging. Este estudo depurou a proteína selenita Capsella bursa (SPC) como objeto de pesquisa, e avaliou as suas características estruturais no alívio da fadiga induzida pelo exercício. O sistema de índice de selenoproteinas para a fadiga induzida pelo exercício foi construído por meio da combinação dos métodos de AHP, análise principal de componentes e a análise de fatores. Foram avaliados a pureza, a composição sub-unitária, a composição de aminoácidos e o conteúdo do RCM. A proteína correspondente do RCM foi prevista preliminarmente. Os resultados mostraram que o SPCH poderia prolongar significativamente o tempo de natação (P < 0.01), melhorar a capacidade de depuração do lactato (P< 0.01), aumentar o conteúdo do glicogênio do fígado (P < 0.01), e reduzir o nível do BUN (P< 0.05). o SPCH tem um bom efeito em aliviar a fadiga induzida pelo exercício em ratos, de modo que pode ser considerado para desenvolvê-lo como um suplemento nutricional para aliviar a fadiga induzida pelo exercício.

RESUMEN La fatiga es un proceso abarcador que envuelve muchos factores fisiológicos y bioquímicos. Es una reacción fisiológica normal cuando las actividades físicas o mentales humanas alcanzan un cierto nivel. En los últimos anos, se verificó que los radicales libres están íntimamente relacionados con la fatiga inducida por el ejercicio. La selenoproteína purificada de Cardamina bursa tiene buena capacidad de depuración de radicales sin oxígeno y de peróxido antilipídico. Podría proteger las mitocondrias, el hígado y los glóbulos rojos de lesiones por peróxido. Por consiguiente, se especuló que la purificación de la selenoproteína de Cardamina puede desempeñar un papel activo en la atenuación de la fatiga inducida por el ejercicio por medio de radicales libres de scavenging. Este estudio depuró la proteína selenita Capsella bursa (SPC) como objeto de investigación, y evaluó sus características estructurales en el alivio de la fatiga inducida por el ejercicio. El sistema de índice de selenoproteínas para a fatiga inducida por el ejercicio fue construido por medio de la combinación dos métodos de AHP, el análisis principal de componentes y el análisis de factores. Fueron evaluados la pureza, la composición sub-unitaria, la composición de aminoácidos y el contenido del RCM. La proteína correspondiente del RCM fue prevista preliminarmente. Los resultados mostraron que el SPCH podría prolongar significativamente el tiempo de natación (P < 0.01), mejorar la capacidad de depuración del lactato (P< 0.01), aumentar el contenido del glicógeno del hígado (P < 0.01), y reducir el nivel del BUN (P< 0.05). el SPCH tiene un buen efecto en aliviar la fatiga inducida por el ejercicio en ratones, de modo que puede ser considerado para desarrollarlo como un suplemento nutricional para aliviar la fatiga inducida por el ejercicio.

Changes of selenium and selenoprotein expressions in diabetic nephropathy / 西安交通大学学报(医学版)

Objective To explore the relationship between selenium and diabetic nephropathy (DN)by determining the selenium content in the plasma and whole blood of DN patients and the changes of selenoprotein expressions in human mesangial cells stimulated by high glucose.Methods We collected the samples and clinical indicators of DN patients and healthy controls to determine selenium content by atomic absorption spectrometry method.The mRNA in human mesangial cells was isolated after stimulation with 30 mmol/L of glucose for 24 hours by Trizol method to detect the changes of selenoprotein expressions by Real-time PCR.We analyzed the differences between DN patients and healthy controls and the relationship between clinical indicators by unpaired t-test and Pearson correlation analysis,respectively.Results The selenium contents in the plasma (P＜0.0001)and whole blood (P＜0.001)were significantly lower in DN patients than in the healthy controls.In addition,plasma selenium contents had a significant negative correlation with renal function and a positive correlation with glycosylated hemoglobin in DN patients.Among the 2 1 human selenoproteins,the mRNAs of Gpx1 ,TrxR2 ,TrxR3 ,Dio2 , Dio3 ,SelK,SelN,SelP,SelR,SelT,SelW and SPS2 were significantly lower in the high-glucose group than in the normal-glucose group which produced by human mesangial cells after high glucose stimulation for 24 hours. Conclusion There was obvious selenium deficiency in DN patients.Human mesangial cells have a significantly low expression of some selenoproteins in the high glucose environment.These results provide clinical and experimental evidence for illuminating the role of low selenium-sensitive selenoproteins in the occurrence and development of DN.

Construction and expression of the recombinant plasmids of truncated and normal selenoprotein S genes / 西安交通大学学报(医学版)

Objective To construct the recombinant plasmids of normal and truncated selenoprotein S genes so as to observe their biological function in vitro or in vivo.Methods We constructed the recombinant plasmids of normal and truncated selenoprotein genes by gene recombinant technology.The gene of truncated selenoprotein was coding domain sequence(CDS)fragment of mRNA;the gene of normal selenoprotein was CDS and 3'untranslated region(including Sec insertion sequence)fragment of mRNA.We confirmed the sequence of recombinant genes by sending them to a company for comparison.The recombinant plasmids of normal and truncated genes of SelS were transfected into cells by Lipofectamine 2000.After 24 hours,the expression of green fluorescent protein was observed and transfection efficiency was detected by FACS analysis.We collected the cells to isolate the total RNA by TRIzol method,and then cDNA was obtained by mRNA reverse transcription and amplified by PCR.Results The sequencing results showed that the recombinant genes were completely the same as the target genes,indicating that we constructed the plasmids successfully.The expression of green fluorescent protein could be observed and transfection efficiency was detected up to 40% by FACS analysis.PCR results showed that the target selenoprotein gene was highly expressed in the experimental group than in control group.Conclusion The truncated and normal selenoprotein S genes were successfully constructed and transfected into cells where they were highly expressed.It lays foundation for observing the biological effect of truncated and normal selenoprotein in cell line or animal body.

Serum selenium and selenoprotein-P levels in autoimmune thyroid diseases patients in a select center: a transversal study

ABSTRACT Objective: Selenium (Se) supplementation has been used to help prevent the progression of Graves' ophthalmopathy (GO) and autoimmune thyroid diseases (AITD) patients. We investigated Se serum and selenoprotein P (SePP) levels in Graves' disease (GD) with and without GO, Hashimoto's thyroiditis (HT) patients and in 27 control individuals (C). Subjects and methods: We studied 54 female and 19 male patients: 19 with GD without GO, 21 GD with GO, 14 with HT and 19 with HT+LT4. Se values were measured using graphite furnace atomic absorption spectrophotometry. Serum SePP levels were measured by ELISA. Results: Median Se levels were similar among all groups; GD patients: 54.2 (46.5-61.1 μg/L), GO: 53.6 (43.5-60.0 μg/L), HT: 51.9 (44.6-58.5 μg/L), HT+LT4 54.4 (44-63.4) and C group patients: 56.0 (52.4-61.5 μg/L); P = 0.48. However, serum SePP was lower in GO patients: 0.30 (0.15-1.05 μg/mL) and in HT patients: 0.35 (0.2-1.17 μg/mL) compared to C group patients: 1.00 (0.564.21 μg/mL) as well as to GD patients: 1.19 (0.62-2.5 μg/mL) and HT+LT4 patients: 0.7 (0,25-1.95); P = 0.002. Linear regression analysis showed a significant relationship between SePP and TPOAb values (r = 0.445, R2 = 0.293; P < 0.0001). Multiple regression analysis found no independent variables related to Se or SePP. Conclusion: A serum Se concentration was lower than in some other countries, but not significantly among AITD patients. The low serum SePP levels in GO and HT patients seems to express inflammatory reactions with a subsequent increase in Se-dependent protein consumption remains unclear.

Advance in the in vivo metabolism and the biological effects of selenium / 药学学报

Selenium (molecular weight 78.96), is a necessary non-metallic trace elements. In recent years, more and more studies have found that selenium is closely related to human disease and could not be ignored. In this paper, we elucidate the in vivo absorption and metabolism of selenium; the active substance-selenoprotein P and so on; the correlation between selenium and pathogenesis of various diseases such as cardiovascular disease, AD/PD neurodegenerative diseases and cancer, etc. The aim is to achieve a more comprehensive understanding of selenium, and to research the in vivo process and the biological effects of selenium. At the same time, selenoproteins and related mechanisms might also be a new target for drug research and discovery.

Hepatokines as a Link between Obesity and Cardiovascular Diseases

Non-alcoholic fatty liver disease, which is considered a hepatic manifestation of metabolic syndrome, independently increases the risks of developing cardiovascular disease (CVD) and type 2 diabetes mellitus. Recent emerging evidence suggests that a group of predominantly liver-derived proteins called hepatokines directly affect the progression of atherosclerosis by modulating endothelial dysfunction and infiltration of inflammatory cells into vessel walls. Here, we summarize the role of the representative hepatokines fibroblast growth factor 21, fetuin-A, and selenoprotein P in the progression of CVD.

Ebola viral selenoproteins: A metallomics analysis

Ebola virus infection is the present public health problem. The trend of worldwide epidemic becomes the serious consideration for this infection. The Ebola virus infection has main clinical manifestation as acute febrile illness with hemorrhagic episode. The problem of hemostatic disturbance can be seen. Focusing on the pathophysiology, selenium plays an important role in the blood clotting regulation. The study on the selenoprotein of the Ebola virus can be useful for further understanding on the pathology of the infection. Here, the authors use metallomics analysis for assessment of Ebola virus genome. According to this study, the selenoprotein portion within Ebola virus genome can be detected at position 1046-1115.

Se-Hg Dual-element Labeling Strategy for Selectively Recognizing Selenoprotein and Selenopeptide / 分析化学

An endogenous element-label plus exogenous element-tag strategy was proposed for inductively coupled plasma mass spectrometry ( ICP-MS) to screen and discriminate a family of ultratrace but biological important biomolecules. The feasibility of this novel idea has been demonstrated when setting seleno ( SeCys) and Se-containing ( SeMet) proteins ( peptides) as an example. Se-label naturally occurring in the biomole-cules acts an identifier for picking them up out of large amount of various coexisting proteins ( peptides) , and CH3 Hg-tag that can bind to SeCys but not SeMet fulfills the task of discriminating seleno and Se-containing ones based on the Se and Hg signals on ICP-MS. After confirmed using SeCys and GPx1, the Se-Hg dual-element labeling strategy together with ICP-MS was applied to screen and discriminate seleno and Se-contai-ning proteins ( peptides) in the water-soluble extracts of Se-enriched yeast, and seven selenoproteins ( pep-tides) were detected with both 202 Hg and 82 Se signals out of fifteen Se-containing species using RPLC/ICP-MS, providing valuable information for further identification using a high-resolution structure-selective mass spectrometer. This endogenous element-label plus exogenous element-tag dual-element approach implies that ICP-MS is not only able to quantify targeted proteins ( peptides) but also helpful to recognize targeted proteins during a discovery-based proteomic study.

Exendin-4 Inhibits the Expression of SEPP1 and Fetuin-A via Improvement of Palmitic Acid-Induced Endoplasmic Reticulum Stress by AMPK

BACKGROUND: Selenoprotein P (SEPP1) and fetuin-A, both circulating liver-derived glycoproteins, are novel biomarkers for insulin resistance and nonalcoholic fatty liver disease. However, the effect of exendin-4 (Ex-4), a glucagon-like peptide-1 receptor agonist, on the expression of hepatokines, SEPP1, and fetuin-A, is unknown. METHODS: The human hepatoma cell line HepG2 was treated with palmitic acid (PA; 0.4 mM) and tunicamycin (tuni; 2ug/ml) with or without exendin-4 (100 nM) for 24 hours. The change in expression of PA-induced SEPP1, fetuin-A, and endoplasmic reticulum (ER) stress markers by exendin-4 treatment were evaluated using quantitative real-time reverse transcription polymerase chain reaction and Western blotting. Transfection of cells with AMP-activated protein kinase (AMPK) small interfering RNA (siRNA) was performed to establish the effect of exendin-4-mediated AMPK in the regulation of SEPP1 and fetuin-A expression. RESULTS: Exendin-4 reduced the expression of SEPP1, fetuin-A, and ER stress markers including PKR-like ER kinase, inositol-requiring kinase 1alpha, activating transcription factor 6, and C/EBP homologous protein in HepG2 cells. Exendin-4 also reduced the expression of SEPP1 and fetuin-A in cells treated with tunicamycin, an ER stress inducer. In cells treated with the AMPK activator 5-aminoidazole-4-carboxamide ribonucleotide (AICAR), the expression of hepatic SEPP1 and fetuin-A were negatively related by AMPK, which is the target of exendin-4. In addition, exendin-4 treatment did not decrease SEPP1 and fetuin-A expression in cells transfected with AMPK siRNA. CONCLUSION: These data suggest that exendin-4 can attenuate the expression of hepatic SEPP1 and fetuin-A via improvement of PA-induced ER stress by AMPK.

Influence of low-selenium diet on expression of selenium-binding protein 1 and selenoprotein P in mouse liver, kidney and brain tissues / 中国地方病学杂志

Objective To explore the influence of low-selenium diet on expression of selenium-binding protein 1 (SBP1) and selenoprotein P (Sel P) in liver,kidney and brain tissues.Methods C57BL/6 mice were randomly divided into four groups according to body weight:control group,low-selenium treatment for 4-,12-and 24-week groups,10 mice in each group,half male and half female.The control group was fed with normal diet (selenium content was 0.300 mg/kg),distilled water,and sacrificed at the 12th week; low-selenium treatment groups were fed with low-selenium diet(selenium content was 0.015 mg/kg),then sacrificed at the 4th,12th and 24th weeks,respectively.Expressions of SBP1 and Sel P in mouse liver,kidney and brain tissues were determined by Western blotting.Results Expressions of SBP1 and Sel P in low-selenium feed mouse liver tissue at the 4th,12th and 24th weeks were,respectively,as follows 0.11 ± 0.01,0.36 ± 0.01,0.59 ± 0.02 and 0.41 ± 0.01,0.39 ± 0.02,0.25 ± 0.02;in kidney,respectively,as follows 0.60 ± 0.03,0.20 ± 0.02,0.03 ± 0.01 and 0.88 ± 0.01,0.73 ± 0.03,0.85 ± 0.02; in brain,respectively,as follows 0.54 ± 0.03,0.11 ± 0.01,0.01 ± 0.01 and 0.50 ± 0.02,0.49 ± 0.03,0.38 ± 0.02.Expression of Sel P in low-selenium feed mouse liver,kidney and brain tissues was significantly decreased as compared to that of control group(1.00 ± 0.00,1.00 ± 0.00,all P ＜ 0.05),but SBP1 content was reduced at first and then rebounded in kidney,and was in decreasing trend in liver and brain tissues.Conclusion Low-selenium diet has a certain effect on expression of SBP1 and Sel P in mouse liver,kidney and brain tissues.

Increased Selenoprotein P Levels in Subjects with Visceral Obesity and Nonalcoholic Fatty Liver Disease

BACKGROUND: Selenoprotein P (SeP) has recently been reported as a novel hepatokine that regulates insulin resistance and systemic energy metabolism in rodents and humans. We explored the associations among SeP, visceral obesity, and nonalcoholic fatty liver disease (NAFLD). METHODS: We examined serum SeP concentrations in subjects with increased visceral fat area (VFA) or liver fat accumulation measured with computed tomography. Our study subjects included 120 nondiabetic individuals selected from participants of the Korean Sarcopenic Obesity Study. In addition, we evaluated the relationship between SeP and cardiometabolic risk factors, including homeostasis model of insulin resistance (HOMA-IR), high sensitivity C-reactive protein (hsCRP), adiponectin values, and brachial-ankle pulse wave velocity (baPWV). RESULTS: Subjects with NAFLD showed increased levels of HOMA-IR, hsCRP, VFA, and several components of metabolic syndrome and decreased levels of adiponectin and high density lipoprotein cholesterol than those of controls. Serum SeP levels were positively correlated with VFA, hsCRP, and baPWV and negatively correlated with the liver attenuation index. Not only subjects with visceral obesity but also those with NAFLD exhibited significantly increased SeP levels (P<0.001). In multiple logistic regression analysis, the subjects in the highest SeP tertile showed a higher risk for NAFLD than those in the lowest SeP tertile, even after adjusting for potential confounding factors (odds ratio, 7.48; 95% confidence interval, 1.72 to 32.60; P=0.007). CONCLUSION: Circulating SeP levels were increased in subjects with NAFLD as well as in those with visceral obesity and may be a novel biomarker for NAFLD.

Selenoprotein S1: A novel inflammatory gene / 中南大学学报(医学版)

Selenoprotein S1 (SEPS1) , a novel gene involved in the stress response of endoplasmic reticulum and inflammation control. Recent results provide a direct mechanistic link between SEPS1 and the production of inflammatory cytokines, suggesting SEPS1 may play a major role in the mediation of inflammation in IDDM and some other immunological disorders.

Expression and Clinical Significance Of Selenoprotein-P In The Tissues of Colorectal Cancer / 医学研究杂志

Objective To discuss the effect of selenoprotein P (SeP) on occurring and developing of colorectal cancer and its clinical significance by detecting the expression of SeP in adjacent mucosa of colorectal cancer, and in the cancer, metastatic lymph node and metastasis hepatic tissues.Methods Tissue microarray was constructed, the expression of SeP in adjacent mucosa of colorectal cancer, and in the cancer, metastatic lymph node and metastasis hepatic tissues were detected by means of immunohistochemistry.Results The positive rate of SeP were 48.4%,69.5%,66.7% and 61.5% in adjacent mucosa, tumor cell, lymph node metastasis and hepatic metastasis. The expression of adjacent mucosa was significantly lower than that in other three sites(?2=16.53,P

Multiple Variant mRNAs with Different Length Tandem Repeats of (CAYYCC)n Produced from Bovine Selenoprotein P-like Protein Gene

In contrast to selenoprotein Ps (SelPs) from other animal species, bovine selenoprotein P-like-protein (SelPLP) was found to contain a tandem repeat of (CAYYCC)11. During an investigation into whether SelPLP was a bovine substitute for SelP or uniquely bovine, its mRNA was found to consist of multiple variants with different length tandem repeat, namely p(0) with (CAYYCC)11, p(-4) lacking (CAYYCC)4, p(-8) lacking (CAYYCC)8, and p(-9) lacking (CAYYCC)9. Although they were encoded on a single gene locus, neither classical GT-AG nor minor class AT-AC donator-acceptor sequences for alternative splicing were identified. A subsequent S1 protection assay using oligonucleotides, whose sequence may occur as variants, performed against bovine poly(A)+RNA identified a total of nine variants. Judging from the sequence of these variants and the branch point mapping, the consensus sequence for recognition of the donator was CACCCCCAC and of the acceptor and the branch point A nucleotide, ACCCCCAT or ACCCCCATCCCCAT. Furthermore, when the p(0) insert mRNA was expressed in COS-7 cells derived from an African green monkey kidney, cDNAs corresponding to p(-8) and p(-9) could be isolated. Therefore, the bovine SelPLP mRNAs consisted of multiple variants probably due to a novel splicing mechanism which was not bovine-specific but common to other mammals.

Multiple variant mRNAs with different length tandem repeats of (CAYYCC)n produced from bovine selenoprotein P-like protein gene

In contrast to selenoprotein Ps (SeIPs) from other animal species, bovine selenoprotein P-like-protein (SeIPLP) was found to contain a tandem repeat of (CAYYCC)(11). During an investigation into whether SeIPLP was a bovine substitute for SeIP or uniquely bovine, its mRNA was found to consist of multiple variants with different length tandem repeat, namely p(0) with (CAYYCC)(11), p(-4) lacking (CAYYCC)(4), p(-8) lacking (CAYYCC)(8), and p(-9) lacking (CAYYCC)(9). Although they were encoded on a single gene locus, neither classicalGT-AG: nor minor classAT-AC: donator-acceptor sequences for alternative splicing were identified. A subsequent S1 protection assay using oligonucleotides, whose sequence may occur as variants, performed against bovine poly(A)(+)RNA identified a total of nine variants. Judging from the sequence of these variants and the branch point mapping, the consensus sequence for recognition of the donator was CACCCCCAC: and of the acceptor and the branch point A nucleotide,ACCCC: CAT orACCCC: CATCCCCAT. Furthermore, when the p(0) insert mRNA was expressed in COS-7 cells derived from an African green monkey kidney, cDNAs corresponding to p(-8) and p(-9) could be isolated. Therefore, the bovine SeIPLP mRNAs consisted of multiple variants probably due to a novel splicing mechanism which was not bovine-specific but common to other mammals.

A PRELIMINARY APPROACH TO BIOLOGICAL FUNCTION OF SOYBEAN SELENOPROTEIN / 营养学报

Objective: To investigate the biological function of soybean selenoprotein by the study of anti-oxidation,immunological and anticarcinogenic efficacy. Method: The soybean selenoprotein at different doses of Se were fed intra-gastrically in Kunming mice. A low Se feedstuff was used as basic diet. Result: (1) when dose is below 202.5 ?g/kg bw Se, the number of white cell and red cell was increased remarkably, and the activity of GSH-Px and SOD in liver and serum was increased at dose dependent manner, but LPO in serum and liver was decreased noticeably. At level of 607.5?g/kg, all the indices were reversed; (2) A dose-dependent cancer protective effect was expressed in range of 22.5-202.5?g/kg Se of soybean selemoprotein in the diet. Feeding soybean selenoprotein can postpone the death of mice with carcinoma . Total tumour yield was consistently reduced by 78% with 202.5?g/kg supplementation; (3) Any abnormal response was never noticed during all trial by supplementing 202.5?g/kg selenoprotein. Conclusion: The increased effect of anti-oxidation and immunological modulation might be the mechanism of tumour suppression by soybean selenoprotein, and Kunming mice tolerated the soybean selenoprotein very well without any side effects.