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PubMed2004

Identification and analysis of the promoter region of the human hyaluronan synthase 2 gene.

Hyaluronan (HA) is a linear glycosaminoglycan of the vertebrate extracellular matrix that is synthesized at the plasma membrane by the HA synthase (HAS) enzymes HAS1, -2 and -3. The regulation of HA synthesis has been implicated in a variety of extracellular matrix-mediated and pathological processes, including renal fibrosis. We have recently described the genomic structures of each of the human HAS genes. In the present study, we analyzed the HAS2 promoter region. In 5'-rapid amplification of cDNA ends analysis of purified mRNA from human renal epithelial proximal tubular cells, we detected an extended sequence for HAS2 exon 1, relocating the transcription initiation site 130 nucleotides upstream of the reference HAS2 mRNA sequence, GenBank accession number NM_005328. A luciferase reporter gene assay of nested fragments spanning the 5' terminus of NM_005328 demonstrated the constitutive promoter activity of sequences directly upstream of the repositioned transcription initiation site but not of the newly designated exonic nucleotides. Using reverse transcription-PCR, expression of this extended HAS2 mRNA was demonstrated in a variety of human cell types, and orthologous sequences were detected in mouse and rat kidney. Alignment of human, murine, and equine genomic DNA sequences upstream of the repositioned HAS2 exon 1 provided evidence for the evolutionary conservation of specific transcription factor binding sites. The location of the HAS2 promoter will facilitate analysis of the transcriptional regulation of this gene in a variety of pathological contexts as well as in developmental models in which HAS2 null animals have an embryonic lethal phenotype.

Animals↗

PubMed2004

Prevalence of LMP-1 gene in tonsils and non-neoplastic nasopharynxes by nest-polymerase chain reaction in Taiwan.

BACKGROUND: The purpose of this study was to investigate the frequency of Epstein-Barr virus (EBV) latent membrane protein-1 (LMP-1) in tonsils and non-neoplastic nasopharynxes in Taiwan. METHODS: Nest-polymerase chain reaction (nest-PCR) was used to examine the presence of LMP-1 gene in lymphoid hyperplasia from non-neoplastic tonsillar and nasopharyngeal tissues and in tonsillar cancers. RESULTS: In 152 cases, 64 biopsy tissues were obtained from lymphoid hyperplasia of nasopharynxes, 57 from tonsillectomy of non-neoplastic tonsils, and 31 from tonsillar cancers. LMP-1 was detected in 43.4% of the study group. Nineteen (29.7%) and 29 (50.9%) lymphoid hyperplasias from normal nasopharynxes and tonsils, respectively, and 18 (58.1%) biopsies from tonsillar cancers had positive LMP-1. The 30-base pair (bp) deleted variant was detected in 89.5% and 82.8% of normal nasopharynxes and tonsils, respectively, and in 66.7% of biopsies from tonsillar cancers (p =.198). CONCLUSION: This study found that the 30-bp variant was the predominant type of LMP-1 from a healthy population in Taiwan.

Asian People↗

PubMed2006

PCR-based clonality analysis of B-cell lymphomas in paraffin-embedded tissues: diagnostic value of immunoglobulin kappa and lambda light chain gene rearrangement investigation.

Polymerase chain reaction (PCR)-based analysis, employed for detecting immunoglobulin heavy chain (IgH) gene rearrangements, has become a diagnostic tool widely used in the investigation of B-cell lymphomas, but the overall sensitivity of these methods does not exceed 80%, notably in germinal center (GC) and post-GC B-cell origin lymphomas. Many PCR strategies devised for detecting immunoglobulin light chain (IgL) gene rearrangements have been developed to enhance the clonality detection rates. However, the feasibility of these methods in routine clinical diagnosis using paraffin-embedded tissues has not yet been investigated sufficiently. We studied a large series of 108 cases of B-cell lymphomas, as well as 20 reactive lymphoid tissues using degenerate primers to amplify immunoglobulin kappa (Igkappa) and lambda (Iglambda) light chain genes. B-cell clonality was further investigated using semi-nested PCR for IgH gene rearrangements. B-cell clonality was detected in 74%, 56.5%, and 43.5% of cases using IgH, Igkappa, and Iglambda PCR, respectively. By combining these methods, the clonality detection rate increased to 93.5%. Only polyclonal patterns were noted in reactive lymphoid samples. We concluded that in addition to the established methods for IgH analysis, a PCR-based approach for IgL gene rearrangements analysis improves the clonality detection rate in over 90% of B-cell lymphoma cases using routine histological specimens with poor preservation of the genomic DNA.

Clone Cells↗

PubMedDate not supplied

Mutation prevalence among 51 unrelated Spanish patients with Gaucher disease: identification of 11 novel mutations.

Gaucher disease is an autosomal recessive disorder caused by mutations in the lysosomal beta-glucocerebrosidase (GBA) gene. Gaucher disease is a very heterogeneous entity due to the large number of different mutations existing in the GBA gene, resulting in a defective protein whose impaired activity is the cause of the disease. We present a mutation analysis of the GBA gene in 51 unrelated Spanish Gaucher disease patients together with clinical findings. Two common mutations, c.1226A>G (N370S) and c.1448T>C (L444P), were determined by restriction enzyme digestion after PCR amplification of genomic DNA. The remaining alleles were screened by amplifying the entire GBA gene followed by nested PCR and SSCP analysis under four different conditions. The c.1226A>G (N370S) and c.1448T>C (L444P) mutations were common, accounting for 56 alleles (55%) and 16 alleles (15%), respectively. In addition, 25 different mutations were found, 11 of which are described here for the first time: c.(-203)A>G, c.160G>A (V15M), c.256C>T (R47X), c.445-2a>g (IVS4-2a>g), c.485T>C (M123T), c.914C>T (P266L), c.953delT, c.1124T>C (L336P), c.1207A>C (S364R), c.1214delG,C, and c.1510delT,C,T (465delSer). Two mutations, S364R and P266L, were associated with neuronopathic forms of Gaucher disease: S364R mutation in heterozygosity with the L444P mutation and the P266L mutation in a homozygous state. Two type 1 patients were found to be carriers of two mutations in the same allele (genotypes [N370S] + [E326K + N188S] and [N370S] + [IVS4-2a>g+c.(-203)A>G]). This study allowed us to identify 100% of mutant alleles, and therefore we conclude that the method used to screen for mutations in the GBA gene is very reliable and there is a broad spectrum of mutations in the GBA gene in the Spanish population.

Adolescent↗

PubMedDate not supplied

Is AML1/ETO gene expression a good prognostic factor in pediatric acute myeloblastic leukemia?

To assess the clinical significance of AML1/ETO gene detected by nested reverse transcriptase polymerase chain reaction, the outcome of 7 patients with acute myeloblastic leukemia between 3 and 14 years of age were presented. All patients had complete remission (CR) at the end of induction (AML-MRC 10 protocol) and 4 underwent unpurged autologous, 2 allogeneic (from matched siblings) non-T-cell-depleted bone marrow transplantations (BMT) in first CR. One patient died due to allogeneic BMT-related complications, and 4 patients relapsed at 13, 17, 18, and 26 months. Only one patient achieved second CR. All relapsed patients died between 18 and 36 months with resistant disease (n = 3) or infection during salvage chemotherapy (n = 1). Two patients who had autologous BMT are alive and disease free at 44 and 50 months. Although statistical significance could not be shown, event-free survival and overall survival rates of AML1/ETO-positive patients (28.57 and 28.57%, respectively) at 3.5 years were even lower than those of AML1/ETO-negative patients. The results confirm some previous reports that AML1/ETO gene in children and adolescents is not a favorable prognostic factor.

Adolescent↗

PubMed1999

Mixed-function supraoperons that exhibit overall conservation, albeit shuffled gene organization, across wide intergenomic distances within eubacteria.

Nearly identical mixed-function supraoperons (defined as nested transcriptional units encoding gene products that function in more than one biochemical pathway) have been found recently in Pseudomonas stutzeri and Pseudomonas aeruginosa. The Pseudomonas serC(pdxF)-aroQp.pheA-hisHb-tyrAc-aroF+ ++-cmk-rpsA supraoperon encodes 3-phosphoserine aminotransferase, a bidomain chorismate mutase/prephenate dehydratase, imidazole acetol-phosphate aminotransferase, cyclohexadienyl dehydrogenase, 5-enolpyruvylshikimate 3-phosphate synthase, cytidylate kinase, and 30S ribosomal protein S1. These enzymes participate in the biosynthesis of serine, pyridoxine, histidine, phenylalanine, tyrosine, tryptophan, and aromatic pathway vitamins and cytidylic acid, in addition to the general role of RpsA in the process of protein synthesis. Features that suggest supraoperon-wide translational coupling are the highly compressed intergenic spacing (including overlapping stop and start codons), as well as possible hairpin structures in mRNA, which could sequester many of the ribosome-binding sites. The hisH-tyrA-aroF segment corresponds to the distal genes of the classic Bacillus subtilis supraoperon. Extensive comparative analysis of the member genes of both the Bacillus and Pseudomonas supraoperons from organisms represented in the entire database revealed unmistakable organizational conservation of these genes across wide phylogenetic boundaries, although considerable gene shuffling was apparent. The persistence of aroE-aroB, hisHb-tyrA-aroF, and cmk-rpsA throughout both the gram-negative and gram-positive assemblages of bacteria, but the absence in Archaea, suggests an ancestral gene organization that occurred in bacteria after the separation of the bacterial and archaeal domains. In gram-negative bacteria,the hisHb-tyrAc-aroF grouping may have been expanded (as with the Pseudomonas supraoperon) and then subsequently collapsed (as with the Escherichia serC-aroF supraoperon) via gene shuffling that is herein equated with gene fusion events.

Amino Acid Sequence↗

PubMed1997

Localization of upstream silencer elements involved in the expression of cone transducin alpha-subunit (GNAT2).

PURPOSE: To localize cis-acting elements involved in the expression of the cone-specific G-protein, cone transducin alpha-subunit (GNAT2). METHODS: In this study, the authors used a genomic clone, HGLG3, to sequence 3139 base pairs of the upstream region of the GNAT2 gene and to localize cis-acting elements involved in the expression of GNAT2. Upstream elements were localized functionally by transfection of chloramphenicol acetyltransferase gene constructs containing nested deletions of this upstream region into WERI-Rb1 cells. Cell specificity of the localized elements was determined by transfection of the HeLa cells. Trans-acting factor-binding sites to functional cis-acting elements were determined by DNasel footprinting. Cell specificity of protein interaction with footprinted regions was tested by electrophoretic mobility shifts with nuclear extracts from WERI-Rb1 and HeLa cells. RESULTS: Transfection of WERI-Rb1 and HeLa cells revealed the presence of a strong, noncell-specific silencer region between -1130 and -23, a weak, cell-specific promoter between -151 and -10, and a stronger, noncell-specific element between +143 and +167. DNaseI footprinting showed three major footprints (S1, S2, and S3) between -807 and -176, indicating the binding sites for putative negative trans-acting factors. Individual footprinted sequences had similar electrophoretic mobility shifts when they were incubated with nuclear extracts from either WERI-Rb1 or HeLa cells, suggesting that these cells express the same negative factors. CONCLUSIONS: The expression of the GNAT2 gene is controlled by a strong silencer region, a weak upstream cell-specific promoter, and a strong downstream element. The silencer region interacts with similar proteins from retina- and nonretina-derived cell lines.

Base Sequence↗

PubMed1996

Retrofitting high molecular weight DNA cloned in P1: introduction of reporter genes, markers selectable in mammalian cells and generation of nested deletions.

The bacteriophage P.1. cloning system is proving to be quite useful for the cloning and analysis of genomic DNA inserts of up to 95 kb in size. In an effort to use that DNA directly in biological experiments we have embarked on a scheme to retrofit the P.1. DNA using a mini-Tn10 transposon system. This transposon system is used in two ways: (i) to introduce a variety of sequence signals that are recognizable in mammalian cells, such as mammalian cell-responsive resistance markers and reporter genes, and (ii) to generate a nested set of deletions in a P.1. clone by using a ioxP site located within the transposon. In this report we show that such transpositions into P.1. DNA are efficient, distributed throughout the entire length of the genomic fragment and do not disrupt the DNA in any location other than the site of insertion of the transposon. The Tn10-based P.1. transduction system described here provides a general scheme for retrofitting any large genomic DNA cloned in a P.1. vector, thus facilitating the use of clones from the current P.1. recombinant libraries in cellular transformation studies.

Animals↗

PubMed2005

[Genotyping of major outer membrane protein gene of Chlamydia trachomatis by cleavase fragment length polymorphism analysis].

OBJECTIVE: To establish a methed of cleavage fragment length polymorphism (CFLP) analysis with a primer labeled at the 5'-end with digoxigenin for genotyping of Chlamydia trachomatis (Ct). The methods for detection of Ct by major outer membrane protein (MOMP) gene (ompl) with nested polymerase chain reaction (ompl-nPCR) were studied. The incidence of Ct infection in pregnant women, the common genotypes and vertical transmission rate of Ct in Chongqing area during the past one year was also investigated. METHODS: The samples were taken from cervical scrapes of parturient women and nasopharygeal swabs of their neonates from April 2003 to Feb. 2004 in Chongqing Women and Children's Health Care Institute. Totally 300 pairs (605 specimens) were detected by using ompl-nPCR, ompl-PCR (inside pair of primers was used directly) and plasmid-PCR. The results were judged by the modified gold standard (MGS). The ompl-nPCR amplified DNA was purified by recovery of DNA from agarose gel electroelution into dialysis bags. The DNA amplified from ompl-nPCR was sequenced by ABI PRISM 377 DNA sequencer. CFLP assay with a primer labeled at the 5'-end with digoxigenin was created for genotyping of Ct, and was primarily applied. RESULTS: The minimum detectable levels of ompl-nPCR and ompl-PCR corresponded to 2.5 elementary body (EB) and 25 EB, respectively. The sensitivity of ompl-nPCR was 10 times that of ompl-PCR. The positive rate of Ct in the samples from the pregnant women was 11% (33/300). The vertical transmission rate of Ct from mothers to their infants was 24.2% (8/33). The rate of Ct isolated from nasopharyngeal swabs 5 - 10 days after birth was 38.9% (7/18), which was significantly greater than that [3.0% (1/33)] detected within 24 hours after birth (chi(c)(2) = 8.79, P < 0.01). Of the 33 Ct-positive samples from pregnant women, 9 had vaginal delivery and 24 had caesarean section. The vertical transmission rates in vaginal delivery group and caesarean section group were 66.7% (6/9) and 8.3% (2/24), respectively (chi(c)(2) = 9.16, P < 0.01). Incidence of premature rupture of membrane in Ct-positive group was 30.3% (10/33), which was greater than that of Ct-negative groups (13.5%, 36/267, chi(2) = 6.40, P < 0.05). Four different patterns were observed in the 16 Ct-positive samples from 8 pregnant women and 8 matched maternal-infants by using CFLP, which were confirmed by DNA sequencing later. They were type E (3 pairs), type F (2 pairs), type H (2 pairs) and type D (1 pair). Each pair of matched maternal-infantile samples presented identical CFLP pattern. CONCLUSIONS: This study revealed the infection rate of Ct in pregnant women, vertical transmission rate of Ct and the common genotypes of Ct in Chongqing Women and Children's Health Care Institute. The CFLP assay by using a primer labeled at the 5'-end with digoxigenin was first used for genotyping of Ct. The assay showed a good sensitivity and reproducibility, no radioactive contamination, and is simple. Therefore the assay is a potential new method for Ct genotyping.

Cervix Uteri↗

PubMed1999

Multiplex PCR--a rapid screening method for detection of gene rearrangements in childhood acute lymphoblastic leukemia.

Chromosomal rearrangements in childhood acute lymphoblastic leukemia (ALL) play an important role in the identification of clinical relevant subgroups. For rapid and easy detection of the clinically most important gene rearrangements, a nested multiplex reverse transcriptase polymerase chain reaction (multiplex PCR) was developed. This multiplex PCR enables the detection of M-BCR/ABL, m-BCR/ABL, TEL/ AML1, and MLL/AF4 fusion transcripts in one PCR reaction. However, the existence of splicing variants and different breakpoints on the DNA level hampers the discrimination of the rearrangements by their fragment size on an agarose gel. Therefore, one of the internal primers of each translocation (ABL-2, TEL-2, AF4-2) was labeled with a characteristic fluorescent dye, and an automatic fluorescence-based DNA fragment analysis was performed. The sensitivity of this multiplex PCR is in the same range as that of the corresponding single PCR reaction and allows a fast screening for the detection of therapy-relevant rearrangements, with a high turnover of samples.

Base Sequence↗

PubMed2001

A rapid real-time quantitative polymerase chain reaction for hepatitis B virus.

Quantification of hepatitis B virus (HBV) DNA in serum is important for monitoring treatment. A rapid and cost effective alternative to the methods available currently was developed based on a real-time quantitative polymerase chain reaction (PCR) done in the LightCycler apparatus. Primers and a probe for sequences of the surface gene of HBV were designed and quantification achieved by reference to standards containing known concentrations of the target sequence. A single copy of the HBV genome could be detected if present in the reaction mixture. The quantitative range of the assay was from 4 x 10(2) to 1.3 x 10(10) surface gene copies/ml serum. Nested PCR was required for quantification in the lower part of this range (<10(5) copies). The real-time PCR and Amplicor Monitor (Roche) tests performed comparably at virus concentrations below 10(6) copies/ml. The commercial test underestimated higher concentrations of virus.

Computer Systems↗

PubMed1998

Receptor editing and commitment in B lymphocytes.

B cells that fail to pass a developmental checkpoint, either as immature or mature B cells, can be rescued by creating a new B cell antigen receptor through nested secondary immunoglobulin gene rearrangements, a process termed receptor editing. Tolerance-mediated receptor editing occurs in self-reactive immature bone marrow B cells, while peripheral receptor editing probably occurs in low-affinity B cells competing for antigen and for survival signals within the germinal center response.

Animals↗

PubMed2003

Virus multiplication and induction of apoptosis by Sendai virus: role of the C proteins.

Sendai virus (SeV) P gene encodes a nested set of carboxyl-coterminal proteins (C', C, Y1 and Y2), which are referred to collectively as the C proteins. Characterization of the virus multiplication and cellular responses in HEp-2 cells infected with the recombinant SeV which lacks two (C' and C), three (C', C and Y1) or all the four C proteins revealed that all the recombinant viruses can grow in the cells to various extents, depending, apparently, on the number of species expressing C protein. In reverse proportion to the viral growth ability, these viruses induced apoptosis in the infected cells. These results indicate that Y2 protein has an antiapoptotic activity, and suggest that this activity works in an additive manner with the longer C protein(s) (C' and/or C) of SeV in order to suppress virus-induced apoptosis in the SeV-infected cells. Apparently, the antiapoptotic activity of the C proteins supports virus multiplication in the infected cells.

Animals↗

PubMed1998

Receptor editing occurs frequently during normal B cell development.

Allelic exclusion is established in development through a feedback mechanism in which the assembled immunoglobulin (Ig) suppresses further V(D)J rearrangement. But Ig expression sometimes fails to prevent further rearrangement. In autoantibody transgenic mice, reactivity of immature B cells with autoantigen can induce receptor editing, in which allelic exclusion is transiently prevented or reversed through nested light chain gene rearrangement, often resulting in altered B cell receptor specificity. To determine the extent of receptor editing in a normal, non-Ig transgenic immune system, we took advantage of the fact that lambda light chain genes usually rearrange after kappa genes. This allowed us to analyze kappa loci in IgMlambda+ cells to determine how frequently in-frame kappa genes fail to suppress lambda gene rearrangements. To do this, we analyzed recombined VkappaJkappa genes inactivated by subsequent recombining sequence (RS) rearrangement. RS rearrangements delete portions of the kappa locus by a V(D)J recombinase-dependent mechanism, suggesting that they play a role in receptor editing. We show that RS recombination is frequently induced by, and inactivates, functionally rearranged kappa loci, as nearly half (47%) of the RS-inactivated VkappaJkappa joins were in-frame. These findings suggest that receptor editing occurs at a surprisingly high frequency in normal B cells.

Amino Acid Sequence↗

PubMed2002

Possible contribution of microchimerism to the pathogenesis of Sjögren's syndrome.

OBJECTIVES: Microchimerism of foetal cells occurs during most pregnancies. Two autoimmune diseases, systemic sclerosis (SSc) and Sjögren's syndrome (SS), have many clinical and pathological similarities to chronic graft-vs-host disease (GVHD). These findings suggest that anti-maternal graft-vs-host reaction by foetal cells may be involved in the pathogenesis of the diseases. To explore this hypothesis, we examined foetal DNA in peripheral blood of 59 women and in salivary glands from 28 women. METHODS: DNA extracted from peripheral blood and the affected minor salivary glands was analysed for the Y-chromosome-specific gene using a nested polymerase chain reaction (PCR) test. In the minor salivary gland specimens, the Y-chromosome-positive foetal cells were identified by in situ hybridization with a Y-chromosome-specific DNA probe. RESULTS: In peripheral blood, there was no significant difference between controls and patients with SSc or SS. In salivary glands, foetal DNA was detected in 11 of 20 women with SS but in only one of eight normal controls using PCR test. Additionally, foetal cells were clearly detected in three out of eight women with SS by the use of in situ hybridization. CONCLUSIONS: The identification of foetal cells in salivary glands suggests that anti-maternal GVHD may be involved in the development of SS.

Adult↗

PubMed2003

Patterns of metastases in familial and non-familial melanoma.

Family history is a strong risk factor for the development of primary melanoma and is associated in a subset with inherited mutations in melanoma susceptibility genes. This study sought to determine whether differences in metastatic pattern exist between patients with a positive family history (FH+) and those with a negative family history (FH-). Such differences could have importance for clinical management and in the determination of the function of both known and putative melanoma susceptibility genes. A retrospective, nested case-controlled study was performed. Of the FH+ cohort (n = 38), 26 were from kindreds with two histologically verified affected first-degree relatives and 12 were from kindreds with three or more affected members, at least two of whom were first-degree relatives. Three FH- controls from the Sydney Melanoma Unit database were matched to each case for age, sex, stage at diagnosis, number of primary melanomas and year of diagnosis (n = 114). There were no statistically significant differences between the two groups with regard to overall survival from initial diagnosis (FH+, 57.4 months; FH-, 50.0 months; P = 0.99), median survival from time of first metastasis (FH+, 15.4 months; FH-, 15.9 months; P = 0.94), or median disease-free interval (FH+, 26.4 months; FH-, 29.7 months; P = 0.73). On multivariate conditional logistic regression analysis, there was no statistically significant difference between the two groups in the probability of developing initial metastases or of ever developing metastases at specific sites. Survival, disease-free interval and distribution of metastatic sites are similar in both familial and non-familial melanoma. Genetic susceptibility for melanoma may lower the threshold for entering an otherwise common molecular pathway for tumour development and evolution.

Adolescent↗

PubMed2003

Real-time PCR to improve the diagnosis of respiratory syncytial virus infection.

Respiratory syncytial virus (RSV) is one of the most important virus respiratory pathogens in infants and young children. A rapid and sensitive diagnosis is essential to focus any outbreak due to this virus. A real-time RT-PCR method was designed using a primer/probe pair from the F gene. Simultaneously with nested RT-PCR and antigen ELISA, 71 consecutive specimens from hospitalized children with clinical symptoms of acute respiratory distress were evaluated to confirm the incidence of RSV infection. RSV was detected in 25 (35.2 %) specimens by real-time RT-PCR and in 19 (26.7 %) by nested RT-PCR. The assay was specific for RSV. The procedure offers a rapid and sensitive alternative to conventional RT-PCR. Closed-tube detection eliminates the risk of contamination.

Antigens, Viral↗

PubMed2002

Tomato bushy stunt virus genomic RNA accumulation is regulated by interdependent cis-acting elements within the movement protein open reading frames.

This study on Tomato bushy stunt virus identified and defined three previously unknown regulatory sequences involved in RNA accumulation that are located within the 3'-proximal nested movement protein genes p22 and p19. The first is a 16-nucleotide (nt) element termed III-A that is positioned at the very 3' end of p22 and is essential for RNA accumulation. Approximately 300 nt upstream of III-A resides an approximately 80-nt inhibitory element (IE) that is obstructive to replication only in the absence of a third regulatory element of approximately 30 nt (SUR-III) that is positioned immediately upstream of III-A. Inspection of the nucleotide sequences predicted that III-A and SUR-III can form looped hairpins. A comparison of different tombusviruses showed, in each case, conservation for potential base pairing between the two predicted hairpin-loops. Insertion of a spacer adjacent to the predicted hairpins had no or a minimal effect on RNA accumulation, whereas an insertion in the putative III-A loop abolished genomic RNA multiplication. We conclude that the sequences composing the predicted III-A and SUR-III hairpin-loops are crucial for optimal RNA accumulation and that the inhibitory effect of IE surfaces when the alleged interaction between SUR-III and III-A is disturbed.

Genes, Regulator↗