Transferring a Gene Expression Cassette Lacking the Vector Backbone Sequences of the 1Ax1 High Molecular Weight Glutenin Subunit into Two Chinese Hexaploid Wheat Genotypes

1Ax1 high molecular weight glutenin subunit （HMW-GS） gene expression cassette （GEC） lacking vector backbone sequences together with selectable marker Bar GEC were co-transformed into Chinese hexaploid cultivars Een 1 and Emai 12 to test the feasibility and the efficiency of explant regeneration, transformation frequency and transgene expression comparing with whole vector transformation by the approaches of plasmid extraction and excision, immature embryo isolation, particle co-bombardment, tissue culture, DNA extraction, PCR amplification, southern hybridization, leaf-painting test and SDS-PAGE etc. No significant difference was shown in tissue culture response of the proportion of embryogenic calli, somatic embryogenesis and regeneration frequency between GEC and whole plasmid bombarded embryos, but both regenerated less well than non-bombarded control. Total 56 plantlets that survived PPT selection had insertion of at least the Bar gene, 18 were from the GEC treatment and 38 from the whole plasmid treatment, the escape ratio averaged 0.23. Six independent transplants f230 - f235 with GEC transformation from genotype Emai 12 presented clear PCR amplification bands of Bar and 1Ax1 gene. The transformation and co-transformation frequency were 3.51 and 100% respectively. PCR amplification using a primer-pair specific for ampicillin resistant gene indicated the existence of Amp^R gene in whole vectors but the removal in GECs and transplants. Southern blot of total DNA and PCR products from transgenic plants of 1Ax1 GEC confirmed the integration of the transgene 1Ax1 and the absence of the EcoR Ⅰ recognition site at both ends of the 1Ax1 GEC when integrated. SDS-PAGE showed the expression of 1Ax1 GEC and un-expression of whole plasmid. The length of integrated fragment, the proportion of the gene of interest （GOI） and the selectable marker （MG）, bombardment pressure and genotypes are vital for the expression of a transformed GEC.

ATP-binding cassette transporters in progression and clinical outcome of pancreatic cancer: what is the way forward?

Pancreatic ductal adenocarcinoma(PDAC) is one of the most aggressive diseases and is characterized by high chemoresistance, leading to the lack of effective therapeutic approaches and grim prognosis. Despite increasing understanding of the mechanisms of chemoresistance in cancer and the role of ATPbinding cassette(ABC) transporters in this resistance, the therapeutic potential of their pharmacological inhibition has not been successfully exploited yet. In spite of the discovery of potent pharmacological modulators of ABC transporters, the results obtained in clinical trials have been so far disappointing, with high toxicity levels impairing their successful administration to the patients. Critically, although ABC transporters have been mostly studied for their involvement in development of multidrug resistance(MDR), in recent years the contribution of ABC transporters to cancer initiation and progression has emerged as an important area of research, the understanding of which could significantly influence the development of more specific and efficient therapies. In this review, we explore the role of ABC transporters in the development and progression of malignancies, with focus on PDAC. Their established involvement in development of MDR will be also presented. Moreover, an emerging role for ABC transporters as prognostic tools for patients' survival will be discussed, demonstrating the therapeutic potential of ABC transporters in cancer therapy.

Characterization of integrons and novel cassette arrays in bacteria from clinical isloates in China,2000-2014

Rapid dissemination of antibiotic resistance genes among bacterial isolates is an increasing problem in China. Integron, a conserved DNA sequence, which is carried on episomal genetic structures, plays a very important role in development of antibiotic resistance. This systematic analysis was based on MEDLINE and EMBASE databases. We summarized the distribution and proportion of different types of gene cassette arrays ofintegrons （including class 1, 2, 3 and atypical class 1 integron） from clinical bacteria isolates in China. Fifty-six literatures were included in this study. Most of the strains were Gram-negative bacteria （94.1%, 7,364/7,822） while only 5.9% strains were Gram- positive bacteria. Class 1 integrons were detected in 54.2% （3956/7295） Gram-negative strains, aadA2 was the most popular gene cassette array detected from 60 Gram-positive bacteria while dfrA 17-aadA5 were detected in 426 Gram- negative bacteria. This study identified 12 novel gene cassette arrays which have not been previously found in any species. All the novel gene cassette arrays were detected from Gram-negative bacteria. A regional characteristic of distribution of integrons was presented in this study. The results highlight a need for continuous surveillance of integrons and provide a guide for future research on integron-mediated bacteria resistance.

ATP binding cassette C1 (ABCC1/MRP1)-mediated drug efflux contributes to disease progression in T-lineage acute lymphoblastic leukemia

Purpose: In acute lymphoblastic leukemia (ALL), multidrug resistance is often mediated by AT- Pase Binding Cassette (ABC) proteins, which principally involve ABCC1 (multidrug resistance protein 1, MRP1) and ABCB1 (multidrug resistance 1, MDR1). However, direct comparisons between the differential effects of ABCC1 and ABCB1 have been difficult, since identical cell lines with differential expression of these transporters have not been developed. Experimental Design: In this study, we developed and compared the biological profiles of Jurkat cell lines that selectively over-expressed ABCC1 and ABCB1. Vincristine (VCR) plays an important role in the treatment of T-lineage ALL (T-ALL), and is often the first drug given to newly-diagnosed patients. Because of its importance in treatment, we provide descalating, sub-lethal doses of VCR to Jurkat cells, and extended our observations to expression profiling of newly diagnosed patients with T-ALL. Results: We found that VCR-resistant cells over-expressed ABCC1 nearly 30-fold. The calcein AM assay confirmed that VCR-resistant cells actively extruded VCR, and that ABCC1-mediated drug resistance conferred a different spectrum of multidrug resistance than other T-ALL induction agents. siRNA experiments that blocked ABCC1 export confirmed that VCR resistance could be reversed in vitro. Analyses of T-lymphoblasts obtained from 100 newly diagnosed T-ALL patients treated on Children’s Oncology Group Phase III studies 9404 and AALL0434 that induction failure could be could be partially explained by the over-expression of ABCC1 and ABCB1. Conclusions: Taken together, these results suggest that over-expression of ABC transporters plays a contributing role in mediating treatment failure in T-ALL, and underscore the need to employ alternate treatment approaches in patients for whom induction failed or for those with relapsed disease.

Characterization of Class 1 Integron Gene Cassettes among Clinical Bacteria Isolated from One Large Hospital in Northern China

The class 1 integron and complex gene cassettes among different species of clinical isolates in northern China were characterized in this study. 383 clinical isolates were obtained from northern China, and class 1 integrons containing gene cassettes widely distributed among gram negative clinical isolates was observed. We find that the class 1 integron showed positive correlation with multidrug resistance phenotype of gram negative bacteria. In addition, we find that isolates belonged to one species harbored different types of gene cassette arrays, while same types of gene cassette arrays were observed in different species of isolates. The diversity of gene cassette arrays among the isolates indicated the complexity of multidrug resistance in clinical isolates in northern China.

Class Ⅰ integron with a novel cassette array in an ESBL-producing multidrug-resistant Klebsiella pneumoniae isolate

Objective： To analyze the molecular mechanism of integron mediated mulfi-resistanc, e in an ESBL-producing K. pneumoniae NJ 12 isolate. Methods： Susceptibility test was carried out by Kirby-Bauer method. Class Ⅰ, Ⅱ and Ⅲ integrons were detected by integrase gene PCR with primers that annealed to conserved regions of integron-encoded integrase genes intll, intl2 and intl3. The variable region of integron was amplified by integron PCR with primers that targeted the conserved flanking regions, and the product was sequenced. Six aminoglycoside modifying-enzyme genes, including ant（2＂）-Ⅰ, ant（3＂）- Ⅰ, aac（3）- Ⅰ, aac（3）-Ⅱ, aac （6＇）-Ⅰ, and aac（6＇）-Ⅱ , were detected. Results： K. pneumoniae NJ 12 was resistant to nine antibiotics, including piperacillin, ampicillin, cefuroxime, ceftazidime, cefotaxime, aztreonam, streptomycin, gentamicin and amikacin. This isolate was shown that there was positive with class Ⅰ integron, ant（2＂）- Ⅰ , ant（3＂）- Ⅰ , aac（3）-Ⅱ and aac（6＇）- Ⅰ modifying-enzyme genes. Neither class Ⅱ nor Ⅲ integron was detected; DNA sequencing of the fragment amplified by integron PCR revealed a novel cassette array aadR-cat-blaoxa-10/ aadA1. Conclusion： Class I integron with a novel cassette array in an ESBL-producing multidrug-resistant K. pneumon/ae NJ 12 isolate was reported from Nanjing area of China, with the GenBank accession number DQ141319.

ZBM30 suppresses atherosclerosis through up-regulating ATP-binding cassette A1 and G1

Atherosclerosis is the most common cause of cardiovascular diseases, such as myocardial infarction and stroke. The aim of this study was to investigate the effects of a novel compound ZBM30 on atherosclerosis in ApoE- deficient mice and its associated mechanism. ApoE-deficient mice （6 weeks old）, fed an atherogenic high-fat and high cholesterol diet for 8 weeks, were divided into three groups. Two groups were orally administrated ZBM30 （10, 30 nag ~ kg-1） daily for 12 weeks, while the control group was administered saline. Atherosclerotic lesions with en face aortas were evaluated by Sudan IV staining, and lesion areas in aortic sinuses were evaluated by oil red O staining. Necrotic core areas and fibrous cap areas in the lesion were evaluated by henaatoxylin and eosin （HE） staining and Masson＇ s trichronae staining in the aorta sinuses. The effects of ZBM30 on cholesterol accumulation in naacrophages and cholesterol transporters： ATP binding cassette A1 （ABCA1） and ATP binding cassette G1 （AB- CG1） were evaluated by oil red O assay, 3H-cholesterol efflux assay, Western blot, and real-time PCR on macro- phage cell lines： Raw 264.7 and THP-1. Inanauno-fluoresces was used to determine the ABCA1 expression in naac- rophage in aorta sinuses. Luciferase reporters of wild type and mutant types of ABCA1 promoter were constructed to determine the regulatory domain of ZBM30 on ABCA1 promoter. Results showed that, compared with the control group, en face lesions in ZBM30 group （ 10, 30 mg · kg^-1 ） were reduced 54.96 ± 10.06% and 71.50 ± 15.37% respectively, and aorta sinus lesions were reduced 41.85 ± 11.21% and 82.23 ± 8.25% respectively. Necrotic core areas in the ZBM30 group were markedly reduced and fibrous cap areas were not changed. Oil red O staining and 3 H-cholesterol efflux assays on Raw 264.7 cell line revealed that ZBM30 significantly attenuated the cholesterol accumulation in naacrophages by enhancing apolipoprotein AI and HDL mediated cholesterol efflux. Furthermore, ZBM30 induced the protein and naRNA expression of cholesterol transporters such as ABCA1 and ABCG1. Inanauno- fluoresces experiment revealed that ZBM30 induced the ABCA1 expression in naacrophage in the lesion, which is consistent with the results in vitro. Luciferase reporter assay revealed that ZBM30 exerted its effect on ABCA1 via liver X receptor （LXR） binding domain. In conclusion, ZBM30 suppresses atherosclerosis through up-regulating cholesterol efflux via ABCA1 and ABCG1 transporters in ApoE-deficient mice.

Emergence of staphylococcal cassette chromosome mec type Ⅰ with high-level mupirocin resistance among methicillin-resistant Staphylococcus aureus

Objective: To investigate the molecular epidemiology and antimicrobial resistance patterns of methicillin-resistant Staphylococcus aureus(MRSA) among healthcare workers and patients.Methods: MRSA isolates were recovered from nasal swabs collected at a tertiary care hospital of Nepal and confirmed on the basis of Gram staining, conventional biochemical tests, and PCR amplification of mec A gene. PCRs were also used for detection of the different resistance genes and staphylococcal cassette chromosome(SCC) mec types.Antibiotic susceptibility patterns of isolates were assessed by disc diffusion method and minimum inhibitory concentrations were determined by E-test.Results: A total of 29 MRSA were isolated from 536 nasal swabs(5.4%) of health care workers and patients at a tertiary care hospital in Nepal. All isolates were susceptible to amikacin, gentamicin, vancomycin(minimal inhibitory concentrations < 2 mg/m L), tigecycline, tetracycline, nitrofurantoin, rifampicin, quinupristin-dalfopristin, and linezolid. Among the 29 MRSA isolates, resistance to erythromycin(72%), ciprofloxacin(75%), co-trimoxazole(62%), clindamycin(10%), and chloramphenicol(10%) was found, and fifteen isolates(51%)exhibited high-level mupirocin resistance(minimal inhibitory concentrations > 1 024 mg/m L).Fourteen isolates were found harboring the mup A gene and one isolate was found carrying the novel mup B gene. High prevalence(68%) of SCCmec I type was found, followed by SCCmec V(13%) and SCCmec III(3%) among all the MRSA isolates.Conclusions: We found the emergence of SCCmec type I with high-level mupirocin resistance among MRSA in Nepal. Data also suggest that MRSA SCCmec type V strain has spread from the community to the hospital.

INHIBITION OF ACTIVATED K-RAS GENE BY SIRNA EXPRESSION CASSETTES IN HUMAN PANCREATIC CARCINOMA CELL LINE MIAPACA-2

Objective: To construct the small interfering RNA(siRNA) expression cassettes (SECs) targeting activated K-ras gene sequence and investigate the effects of SECs on K-ras gene in human pancreatic cancer cell line MIAPaCa-2. Methods: Three different sites of SECs were constructed by PCR. The K1/siRNA, K2/siRNA and K3/siRNA were located at the site 194, 491 and 327, respectively. They were transfected into MiaPaCa-2 cells by liposome to inhibit the expression of activated K-ras. In the interfering groups of site 194,491, we observed the cytopathic effect of confluent MiaPaCa-2 cells after they were incubated for 48 hours, and detected the apoptosis in cells by FACS, then we tested the alternation of K-ras gene in confluent MiaPaCa-2 cells by RT-PCR,immunofluorescence and western blot, respectively. Results: Introductions of the K1/siRNA and K2/siRNA against K-ras into MiaPaCa-2 cells led to cytopathic effect, slower proliferation and increased apoptosis, while the appearances of control MiaPaCa-2 cells remained well. The number of apoptotic cells increased compared with control cells. RT-PCR,immunofluorescence and western blot showed the effects of inhibited expression of activated K-ras gene by RNA interference in the K1/siRNA and K2/siRNA groups. We also found that the introduction of K3/siRNA had no effect on MiaPaCa-2 cells. Conclusion: K1/siRNA and K2/siRNA can inhibit the expression of activated K-ras and decrease the growth of MiaPaCa-2 cells, while K3/siRNA has no such effect, demonstrating that the suppression of tumor growth by siRNA is sequence-specific. We conclude that K-ras is involved in maintenance of tumor growth of human pancreatic cancer, and SECs against K-ras expression may be a powerful tool to be used therapeutically against human pancreatic cancer.

Inhibiting NF-κB increases cholesterol efflux from THP-1 derived-foam cells treated with AngⅡ via up-regulating the expression of ATP-binding cassette transporter A1

Objective： To study the role of nuclear factor-kappa B（NF- κB） in cholesterol efflux from THP-1 derived-foam cells treated with Angiotensin Ⅱ（Ang Ⅱ ）. Methods：Cultured THP-1 derived-foam cells were treated with Ang Ⅱ or preincubated with tosyl-phenylalanine chloromethyl-ketone（TPCK） NF- κB inhibitor. The levels of activated NF- κB in the cells were examined by sandwich ELISA, Cellular cholesterol content was studied by electron microscopy scanning and zymochemistry via fluorospectrophotometer and cholesterol effiux was detected by scintillation counting technique. ABCA1 mRNA and protein were quantified by RT-PCR and Western blotting. Results：Addition of TPCK to the cells before Ang Ⅱ stimulation attenuated the response of NF- κB p65 nuclear translocation induced by Ang Ⅱ and showed no peak in foam cells group and caused a reduction in cholesterol content and an increase in cholesterol efflux by 24.1%（P〈 0.05） and 41.1%（P〈 0.05） respectively, when compared with Ang Ⅱ group. In accordance, the ABCA1 mRNA and protein were increased by 30% and 19%（P 〈 0.05） respectively, when compared with Ang Ⅱ group. Conclusion：Ang Ⅱ can downregulate ABCA1 in THP-1 derived-foam cells via NF- K B, which leads to less cholesterol effiux and the increase of cholesterol content with the consequence of the promotion of atherosclerosis.

Diversity and Distribution of Staphylococcal Chromosomal Cassettes Mec (SCCmec) Types I, II and III in Coagulase-Negative Staphylococcal Strains Isolated from Surfaces and Medico-Technical Materials of the University Hospital of Abomey-Calavi/Sô-Ava

The coagulase-negative staphylococci (CoNS) have long been considered to be low pathogenicity. The possibility of a horizontal transfer of resistance and virulence genes from S. aureus to CoNS could increase the pathogenicity of these bacteria. The objective of this work is to contribute to a better knowledge of the pathogenicity of (CoNS) strains isolated from surfaces and medico-technical materials of the University Hospital of Abomey-Calavi/Sô-Ava. Seventy strains of CoNS isolated from surfaces and medico-technical materials of the University Hospital of Abomey-Calavi were tested for methicillin resistance. The resistance to methicillin was evaluated phenotypically by the resistance of the strains to cefoxitin and then confirmed by the search for the mecA gene using PCR. The genes encoding staphylococcal chromosomal cassette (SCCmec) types I, II and III originally found in S. aureus were tested in CoNS by multiplex PCR using specific primers. All the strains studied showed resistance to methicillin. However, only 28.5% (20/70) carried the mecA gene. SCCmec was identified in only 17.14% (12/70) of these strains. Four strains carried mecA gene as well as one of the three types of SCCmec searched. SCCmec types I, II and III were identified in CoNS strains studied. SCCmec type I was the most frequent chromosomal cassette in mecA+ strains, only or in association with another SCCmec. The study also revealed methicillin-resistant strains carrying SCCmec lacking the mecA gene. Finally, 60% (12/20) of the strains were found to be non-typeable. Our results show that CoNS strains present a high resistance to methicillin and the source of this resistance in the CoNS of our study is not only the mecA gene. There is also a high diversity of SCCmec, justified by a large number of non-typeable CoNS strains. The mecA− SCCmec+ methicillin-resistant strains deserve to be sequenced for further studies.

Prevalence of Class 1 Integron, Resistance Gene Cassettes and Antimicrobial Susceptibility Profiles among Isolates of Pseudomonas aeruginosa in Iran

Pseudomonas aeruginosa is one of the most important opportunistic human pathogens worldwide. High prevalence of Multi Drug Resistant P. aeruginosa (MDRPa) in Iran is a serious problem for antimicrobial therapy. Several studies have reported the MDRPa in Europe and Asia. Due to the use of broad-spectrum antibiotics, bacterial resistance is increasing in Iran, located in Middle East. The present cross-sectional study was designed to investigate the prevalence of class1 integron, resistance gene cassettes and antimicrobial susceptibility profiles among isolates of P. aeruginosa in Al-Zahra Hospital, Isfahan City, central part of Iran from Jan-Sep 2014. The aim of this study was to determine the antimicrobial susceptibility, the prevalence of Class1 integron, resistance gene a measuring in Iran. A total of 231 P. aeruginosa isolates were collected from clinical specimens including urine (50.6%), tracheal tube (25.5%), wound (13.4%), blood (6.1%), catheter (2.2%), cerebrospinal fluid (1.7%) and sputum (0.4%) isolates from hospitalized patients (mean age: 50.27 ± 24.12 years).The majority of patients (68%) were male. Isolates were collected from different parts of the hospital as follows: ICU, Internal Medicine, Emergency care, Pediatrics, Nephrology, Transplant Center, General surgery and Infectious. Revealed data show a high rate of MDR P. aeruginosa isolates in the studied area;also, the result signifies the spread of aadA6 among clinical isolates in hospitalized patients.

Efficacy of Shoushen granule on adenosine triphosphate binding cassette transporter A1, proprotein convertase subtilisin/kexin type 9 and toll-like receptor 4/nuclear factor kappa-B signaling pathway in ApoE-knockout mice

OBJECTIVE: To evaluate the efficacy of Shoushen granule, prepared with four Chinese medicinals, on the targeted regulation of adenosine triphosphate binding cassette transporter A1(ABCA1) through proprotein convertase subtilisin/kexin type 9(PCSK9) and toll-like receptor 4(TLR4)/nuclear factor kappa-B(NF-κB) signaling pathway to affect atherosclerosis(AS) in ApoE-knockout(ApoE-/-) mice.METHODS: ApoE-/-mice fed with a high-fat diet were used for AS modeling and divided into Model,Shoushen, and Atorvastatin groups. C57 BL/6 J mice at the same age and background strain were included in the Control group. Western blot and immunohistochemistry were used to measure ABCA1, PCSK9, TLR4, and NF-κB protein expression in mouse aortas. Enzyme-linked immuno sorbent assay was used to measure mouse serum tumor necrosis factor-α(TNF-α), interleukin-10(IL-10), monocyte chemoattractant protein 1(MCP-1), and intercellular cell adhesion molecule-1(ICAM-1) expression. Serum lipid profiles and histopathology were also assessed. Shoushen granule were composed of Heshouwu(Radix Polygoni Multiflori) 15 g, Gouqizi(Fructus Lycii) 15 g, Sheng shanzha(Raw Fructus Crataegus Pinnatifidae) 10 g, and Sanqi(Radix Notoginseng) 3 g.RESULTS: ApoE-/-mice fed with a high-fat diet had notable AS lesions, with reduced ABCA1 and IL-10 levels, elevated PCSK9, TLR4, NF-κB, TNF-α, MCP-1,and ICAM-1 expression, and increased total cholesterol(TC) and low density lipoprotein cholesterol(LDL-C) contents. With drug interventions, the areas of AS plaques were significantly reduced,the ABCA1 and IL-10 levels were increase, while the PCSK9, TLR4, NF-κB, TC, and LDL-C contents,and the TNF-α, MCP-1, and ICAM-1 expression were reduced.CONCLUSION: Shoushen granule effectively interfered with AS development by antagonizing the expression of key factors of the PCSK9 and TLR4/NF-κB signaling pathway to upregulate ABCA1 expression.

Product Variability of the ‘Cineole Cassette＇ Monoterpene Synthases of Related Nicotiana Species

Nicotiana species of the section Alatae characteristically emit the floral scent compounds of the ＇cineole cassette＇ comprising 1,8-cineole, limonene, myrcene, α-pinene, β-pinene, sabinene, and α-terpineol. We successfully isolated genes of Nicotiana alata and Nicotiana langsdorfii that encoded enzymes, which produced the characteristic monoter- penes of this ＇cineole cassette＇ with α-terpineol being most abundant in the volatile spectra. The amino acid sequences of both terpineol synthases were 99% identical. The enzymes cluster in a monophyletic branch together with the closely related cineole synthase of Nicotiana suaveolens and monoterpene synthase 1 of Solanum lycopersicum. The cyclization reactions （α-terpineol to 1,8-cineole） of the terpineol synthases of N. alata and N. langsdorfii were less efficient compared to the ＇cineole cassette＇ monoterpene synthases of Arabidopsis thaliana, N. suaveolens, Salvia fruticosa, Salvia officinalis, and Citrus unshiu. The terpineol synthases of IV. alata and N. langsdorfii were localized in pistils and in the adaxial and abaxial epidermis of the petals. The enzyme activities reached their maxima at the second day after anthesis when flowers were fully opened and the enzyme activity in N. alata was highest at the transition from day to night （diurnal rhythm）.

Investigation of integrons/cassettes in antimicrobial-resistant Escherichia coli isolated from food animals in China

In this study,326 Escherichia coli isolates from food animals collected during the last four decades in China were characterized using antimicrobial susceptibility testing and screening for integrons/cassettes.Minimum inhibitory concentration(MIC) testing indicated that the antimicrobial resistance of E.coli has increased since the 1970s.The findings of this study present a warning to veterinary practitioners about the excessive use of antimicrobials,and suggest the necessity for surveillance and control of antimicrobial resistance in veterinary clinical medicine in China.

How to overcome ATP-binding cassette drug efflux transporter-mediated drug resistance?

P-glycoprotein(ABCB1),multidrug resistance protein-1(ABCC1)and breast cancer resistance protein(ABCG2)belong to the ATP-binding cassette(ABC)superfamily of proteins that play an important physiological role in protection of the body from toxic xenobiotics and endogenous metabolites.Beyond this,these transporters determine the toxicity profile of many drugs,and confer multidrug resistance(MDR)in cancer cells associated with a poor treatment outcome of cancer patients.It has long been hypothesized that inhibition of ABC drug efflux transporters will increase drug accumulation and thereby overcome MDR,but until now no approved inhibitor of these transporters is available in the clinic.In this review we present molecular strategies to overcome this type of drug resistance and discuss for each of these strategies their promising value or indicate underlying reasons for their limited success.

The classification of ATP-binding cassette subfamily A member 3 mutations using the cystic fibrosis transmembrane conductance regulator classification system

Importance: The ATP-binding cassette subfamily A member 3 (ABCA3) protein plays a vital role in surfactant homeostasis. Mutations in the ABCA3 gene lead to the development of interstitial lung disease. In the most severe manifestation, mutations can lead to a fatal respiratory distress syndrome in neonates. ABCA3 belongs to the same ATP-binding cassette transporter superfamily as the cystic fibrosis transmembrane conductance regulator (CFTR), the gene that causes cystic fibrosis. Objective: To classify ABCA3 mutations in a manner similar to CFTR mutations in order to take advantage of recent advances in therapeutics. Methods: Sequence homology between the CFTR protein and the ABCA3 protein was established. The region of CFTR that is a target for the new potentiator class of drugs was of particular interest. We performed a literature search to obtain all published mutations that were thought to be disease causing. We classified these mutations using the established CFTR classification system. When possible, we drew on previous experimental classification of ABCA3 mutations. Results: Although the proteins share the same overall structure, only a 19％identity was established between CFTR and ABCA3. The CFTR therapeutic target region has a 22％ homology with the corresponding ABCA3 region. Totally 233 unique protein mutations were identified. All protein mutations were classified and mapped to a schematic diagram of the ABCA3 protein. Interpretation: This new classification system for ABCA3, based on CFTR classification, will likely aid further research of clinical outcomes and identification of mutation-tailored therapeutics, with the aim for improving clinical care for patients with ABCA3 mutations.

Protective Effect of Irbesartan on ATP Binding Cassette Transporter A1 in THP-1 Derived Macrophages

Objectives To explore the protective effect of irbesartan （lrb） under the interference with angiotensin II （Ang II） on ABCA1. Methods Electron microscopy was used to detect the morphous of foam cells. The expression of ABCA1 mRNA and its protein were determined by RT-PCR and Western blotting, respectively. The variance of cellular cholesterol content was measured by zymochemistry via-fluorospeetrophotometer. Results A positive facilitative effect of Ang II on the formation of foam cells was observed. Total cholesterol was increased significantly by Ang II, the expression of ABCA1 was down-regulated obviously by Ang II; Irb could protect ABCA1 against the lesion of Ang II; Total cellular cholesterol content was reduced significantly in Irb ＋ Ang II group; However, considerable alteration about the cholesterol content and the expression of ABCA1 were not observed in Irb group without incubation with Ang II. Conclusions Irb could protect ABCA1 against the lesion of Ang II, which may contribute to its anti-atherosclerotic properties. （ S Chin J Cardiol 2009; 10（4） ： 227 -233）

Postoperative jaundice related to UGT1A1 and ABCB11 gene mutations:A case report and literature review

BACKGROUND Patients with obstructive jaundice caused by intrahepatic bile duct stones can be effectively managed by surgery.However,some patients may develop postope-rative complications,liver failure,and other life-threatening situations.Here,we report a patient with mutations in the uridine 5’-diphospho-glucuronosyltrans-ferase 1A1(UGT1A1)and bile salt export pump(adenosine triphosphate-binding cassette subfamily B member 11,ABCB11)genes who presented multiple intrahe-patic bile duct stones and cholestasis,and the jaundice of the patient increased after partial hepatectomy.CASE SUMMARY A 52-year-old male patient admitted to the hospital on October 23,2021,with a progressive exacerbation of jaundice,was found to have multiple intrahepatic bile duct stones with the diagnoses of obstructive jaundice and acute cholecystitis.Subsequently,the patient underwent left hepatectomy with biliary exploration,stone extraction,T-tube drainage,and cholecystectomy without developing any intraoperative complications.The patient had a dark urine color with worsening jaundice postoperatively and did not respond well to plasma exchange and other symptomatic and supportive treatments.Since the progressive increase in postoperative bilirubin could not be clinically explained with any potential reason,including,if not at all,viral infection,cholangitis,autoimmune liver disease,and other causes,the patient underwent whole-exon screening for any genetic diseases,which surprisingly identified UGT1A1 and ABCB11 gene mutations related to glucuronidation of indirect bilirubin as well as bile acid transport in hepatocytes,respectively.Thus,we hypothesized that postoperative refractory cholestasis might result from UGT1A1 and ABCB11 gene mutations and further recommended liver transplantation to the patient,who eventually declined it and died from liver failure six months later.CONCLUSION Surgery may aggravate cholestasis in patients with multiple intrahepatic bile duct stones and cholestasis associated with UGT1A1 and ABCB11 gene mutations.A liver transplant may be the best option if active medical treatment fails.

Knocking-Out OsPDR7 Triggers Up-Regulation of OsZIP9 Expression and Enhances Zinc Accumulation in Rice

Zinc(Zn) is an essential trace mineral that is required for plant growth and development. A number of protein transporters, which are involved in Zn uptake, translocation and distribution, are finely regulated to maintain Zn homeostasis in plant. In this study, we functionally characterized an ATP-binding cassette(ABC) transporter gene, OsPDR7, which is involved in Zn homeostasis. Os PDR7 encodes a plasma membrane-localized protein that is expressed mainly in the exodermis and xylem in the rice root.ospdr7 mutants resulted in higher Zn accumulation compared with the wild type. Heterogeneous expression of OsPDR7 in a yeast mutant rescued the Zn-deficiency phenotype, implying transport activity of OsPDR7 to Zn in yeast. However, no ZIP genes except for OsZIP9 showed change in expression profile in the ospdr7 mutants, which suggested that OsPDR7 maintains cellular Zn homeostasis through regulating Os ZIP9 expression. RNA-Seq analysis further revealed a set of differentially expressed genes between the wild type and ospdr7 mutants that allowed us to propose a possible OsPDR7-associated signaling network involving transporters, hormone responsive genes, and transcription factors. Our results revealed a novel transporter involved in the regulation of Zn homeostasis and will pave the way toward a better understanding of the fine-tuning of gene expression in the network of transporter genes.