[Long term results of central hole type posterior chamber intraocular lens in the correction of moderate to high myopia].

Objective: To evaluate the long-term safety,effectiveness,predictability and stability of ICL V4c implantation for moderate to high myopia. Methods: In this retrospective case series study, 95 eyes from 50 patients with moderate to severe myopia who were treated in 2015 underwent central hole type posterior chamber intraocular lens (ICL V4c) implantation at Eye & ENT Hospital of Fudan University. The patients were followed up for a period of five years, during which we assessed various parameters including uncorrected visual acuity (UDVA), corrected visual acuity (CDVA), refractive error, axial length, intraocular pressure, endothelial cell density (ECD), vault, and complications. We used the paired t-test and repeated measures one-way ANOVA in SPSS statistical software to analyze the data. Results: The mean spherical equivalent refraction (SE) decreased significantly from (-12.16±3.04) D preoperatively to (-0.19±0.55) D at one month and (-1.14±0.84) D at five years postoperatively. The safety indices (postoperative CDVA/preoperative CDVA) were 1.24±0.27 and 1.13±0.27, respectively, and the efficacy indices (postoperative UDVA/preoperative CDVA) were 1.14±0.25 and 0.87±0.26 at one month and five years postoperatively. At one month after surgery, 80.00% of the eyes were within ±0.50 D of the expected correction, and 96.84% were within ±1.00 D. There was no significant difference in IOP between preoperative and postoperative measurements. The rate of ECD was 3.87%, and the vault decreased by 106.32 µm at five years postoperatively. Conclusion: ICL V4c implantation is safe and effective with good predictability and stability for long term.

Correlation between the Polymorphism of Coagulation-Related Genes and Lower Extremity Deep Venous Thrombosis.

ABSTRACT: Objective To investigate the correlation between the polymorphism of 4 coagulation-related genes, rs1799963 （coagulation factor V gene Leiden）, rs6025 （prothrombin gene G20210A）, rs1042579 （thrombomodulin protein gene c.1418C>T） and rs1801131 （methylenetetrahydroflate reductase gene） and lower extremity deep venous thrombosis （LEDVT）. Methods The 4 genotypes mentioned above of 150 LEDVT patients and 153 healthy controls were detected by the kompetitive allele specific polymerase chain reaction （KASP）, then related blood biochemical indicators were collected, binary Logistic regression was established to screen the independent risk factors of LEDVT, and the correlation between polymorphism of 4 coagulation-related genes and LEDVT and its indicators under different genetic modes after adjusting confounding factors were analyzed. Results Five variables, D-dimer, fibrinogen degradation product, homocysteine, sex and age might be the risk factors of LEDVT. These variables were put into 4 genetic inheritance models, and adjusted in binary Logistic regression. The results suggested that the mutations of rs1042579 were correlated with LEDVT under dominant inheritance mode. Conclusion The gene polymorphism of rs1799963, rs6025 and rs1801131 has no significant correlation with the formation of LEDVT. The gene polymorphism of rs1042579 plays a role under dominant inheritance mode, and might be an independent risk factor for formation of LEDVT.

[Clinical application value of transthoracic echocardiography during perioperative period in patients undergoing left ventricular assist device implantation].

Objective: To observe the changes of parameters derived from transthoracic echocardiography (TTE) before and after left ventricular assist device (LVAD) implantation, and to evaluate the clinical value of TTE in the perioperative period of LVAD implantation. Methods: This is a retrospective study. The data of patients who underwent LVAD implantation in Fuwai Hospital from January 2018 to December 2020 were analyzed retrospectively. The TTE parameters, N-terminal pro-B-type natriuretic peptide (NT-proBNP) and total bilirubin (TBil) before and 1 month after LVAD implantation were collected and analyzed. Results: A total of 12 male patients undergoing LVAD implantation were included in this study. The mean age was (43.3±8.6) years. The left atrial volume index ((41.4±12.8)ml/m2 vs. (74.9±30.7)ml/m2, P<0.001), left ventricular end-diastolic volume index ((152.1±35.3)ml/m2 vs. (205.5±35.7)ml/m2, P<0.001), left ventricular end-systolic volume index ((112.5±27.9)ml/m2 vs. (155.1±29.1)ml/m2, P<0.001), right atrial diameter index ((23.7±3.5)mm/m2 vs. (27.2±5.8)mm/m2, P=0.023), right ventricular internal diameter at end-diastole ((24.6±2.7)mm vs. (30.0±4.8)mm, P<0.001), tricuspid annular plane systolic excursion ((11.5±2.9)mm vs. (14.6±2.8)mm, P=0.007), systolic pulmonary arterial pressure ((29.2±4.8) mmHg vs. (55.1±19.3) mmHg, P<0.001, 1 mmHg=0.133 kPa) were significantly reduced at 1 month post LVAD implantation as compared to before LVAD implantation. The aortic sinus diameter ((33.8±4.7)mm vs. (31.6±5.1)mm, P=0.007), left ventricular ejection fraction ((26.3±3.0)% vs. (23.8±4.4)%, P=0.016), right ventricular fractional area change ((31.0±8.6)% vs. (23.8±5.5)%, P=0.004) at 1 month post LVAD implantation were significantly higher than before LVAD implantation. The degree of mitral and tricuspid regurgitation decreased, and the inspiratory collapse rate of inferior vena cava increased (all P<0.05). NT-proBNP ((1 418.4±812.6)ng/L vs. (5 097.5±3 940.4)ng/L, P=0.004) and TBil ((12.4±5.4)µmol/L vs. (27.5±14.0)µmol/L, P=0.001) decreased significantly at 1 month post LVAD implantation. Conclusions: TTE results show that LVAD could effectively relieve left ventricular load and improve right ventricular function. TTE can monitor the cardiac structural and functional changes during the perioperative period of LVAD implantation, and provide the imaging evidence for clinical evaluation of the therapeutic effect of LVAD.

Long non-coding RNA LINC00152 is up-regulated in ovarian cancer tissues and regulates proliferation and cell cycle of SKOV3 cells.

OBJECTIVE: To characterize functions of long non-coding RNA (lncRNA) in the progression of epithelial ovarian cancer. PATIENTS AND METHODS: Epithelial ovarian cancer tissues and matching normal tissues were collected from two individual patients for RNA microarray analysis. Besides, twenty-two ovarian cancer samples and ten healthy ovarian epithelial tissues were collected for Reverse Transcription-quantitative Polymerase Chain Reaction (RT-qPCR). Microarray assay suggested that a list of cancer relating mRNAs and lncRNAs were upregulated. The identified lncRNAs were validated via RT-qPCR, which led to the identification of long intergenic non-protein coding RNA 152 (LINC00152). To determine the function of LINC00152 in ovarian cancer, we knocked down the expression of LINC00152 in epithelial ovarian cancer cell line SKOV3 with small interference RNAs (siRNAs). The effects of LIN00152 on the proliferation and cell cycle were determined by comparing the cell viability of SKOV3 cells with LIN00152 knockdown and the control cells with negative siRNA. The cell viability was assessed using Cell Counting Kit-8 (CCK-8) and flow cytometry assay. RNA microarray assay was used again in control and LINC00152 knockdown SKOV3 cells to identify downstream signaling pathways. RESULTS: Fourteen ovarian cancer relating lncRNAs were identified by RNA microarray assay. Up-regulation of LINC00152 was validated via RT-qPCR. A higher expression of LINC00152 in late cancer stage (III-IV) compared to the early stage tumors was also demonstrated. Inhibition of LINC00152 in SKOV3 cells inhibited cell proliferation and induced cell cycle arrest that involved prolonged G1 phase and shortened S phase. The microarray assay data of SKOV3 cells suggested that Cyclin-Dependent Kinase Inhibitor 1C (CDKN1C) was a potential downstream target of LINC00152. CONCLUSIONS: LINC00152 is upregulated in epithelial ovarian cancer tissues comparing to normal tissues. Knockdown of LINC00152 expression inhibits cell proliferation and induces cell cycle arrest. LINC00152 possibly interacts with Tumor Necrosis Factor (TNF) signaling pathway. CDKN1C is a potential downstream target of LINC00152.

Effects of miR-21 on hypertensive rats through PTEN/PI3K/Akt/mTOR signaling pathway.

OBJECTIVE: The aim of this study was to investigate the effects of micro-ribonucleic acid (miR)-21 on hypertensive rats through the phosphatase and tensin homolog deleted on chromosome ten (PTEN)/phosphatidylinositol 3-kinase (PI3K)/protein kinase B (Akt)/mammalian target of rapamycin (mTOR) signaling pathway. MATERIALS AND METHODS: A total of 10 spontaneously hypertensive rats (SHRs) were selected as the model group. Meanwhile, 10 rats with the same age were enrolled in the normal control group. Real Time-fluorescence quantitative Polymerase Chain Reaction (qRT-PCR) was performed to detect the mRNA level of miR-21 in rats of the SHR model group and control group. The tail arterial diastolic pressure of rats in the awake and resting state was measured in both groups, respectively. Pathological sections were prepared to evaluate pathological changes in myocardial tissues. Subsequently, myocardial cells were isolated, cultured and transfected with miR-21 mimics and miR-21 inhibitor, respectively. Transfection efficiency was verified using fluorescence quantitative PCR. Terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) assay was utilized to determine the apoptosis level of myocardial cells. Furthermore, the expression levels of the signaling pathway-related proteins were detected via Western blotting assay. RESULTS: Fluorescence quantitative PCR results revealed that the expression level of miR-21 was significantly higher in the SHR model group (p<0.05). The diastolic pressure increased markedly in the SHR model group when compared with that in the control group (p<0.05). Subsequent hematoxylin and eosin (HE) staining indicated apparent myocardial tissue injury in the SHR model group (p<0.05). After transfection, the results showed that miR-21 inhibitor could effectively down-regulate the expression level of miR-21 in myocardial cells (p<0.05). Meanwhile, TUNEL staining revealed that the number of apoptotic cells in the miR-21 inhibitor group was remarkably higher than that of the other two groups (p<0.05). In addition, Western blotting results manifested that the protein expression levels of PTEN, PI3K, Akt and mTOR were significantly lower in the miR-21 mimics group (p<0.05), whereas was remarkably higher in the miR-21 inhibitor group (p<0.05). CONCLUSIONS: MiR-21 is involved in regulating the pathological symptoms and myocardial cell apoptosis in hypertensive rats through the PTEN/PI3K/Akt/mTOR signaling pathway.

Safety evaluation of subretinal injection of trypan blue in rats.

OBJECTIVE: To determine the appropriate concentration of trypan blue (TB) for subretinal injection in a rat model and to provide a safety profile that limits retinal toxicity while maintaining dye visibility. MATERIALS AND METHODS: Adult rats were subretinally injected with various concentrations of either TB or phosphate-buffered saline (PBS); rats which received sham injections served as an additional control. The injected areas were visualized under a surgical microscope. Electroretinography (ERG) was performed to measure retinal function. Animals were then sacrificed, and the eyes were sectioned and examined by light microscopy. Terminal deoxynucleotidy1 transferase dUTP nick-end labeling (TUNEL) was applied to determine retinal apoptosis. RESULTS: One day after the subretinal injection, TB stains were visible under the surgical microscope in the 0.2%, 0.08%, and 0.04% TB-injected groups, but not in the 0.02% TB-injected group. TB stain was detectable in the retina and sclera of the 0.2%, 0.08%, and 0.04% TB-injected groups for over 2 weeks after injection. However, the amplitudes of ERGa- and b-waves were affected and became significantly lower in the 0.2% TB-injected group than the amplitudes in the PBS-, or sham-injected group. Moreover, TUNEL+ cells appeared in the outer nuclear layer (ONL), ganglion cell layer (GCL), and retinal pigment epithelium (RPE) layer of the 0.2% and 0.08% TB-injected groups at 1 and 7 days after subretinal injection. In contrast, very few TUNEL+ cells were found in the 0.04% TB- or PBS-injected group. Two weeks after injection, the ONL was significantly thinner in the 0.2% TB-injected group than in the 0.04% TB-, PBS- or sham-injected group. CONCLUSIONS: TB injection induces a dose-dependent neurotoxic effect on retinal cells. Subretinal injection of 0.04% TB is relatively safe and effective for subretinal staining.

Characterization, culture medium optimization and antioxidant activity of an endophytic vitexin-producing fungus Dichotomopilus funicola Y3 from pigeon pea [Cajanus cajan (L.) Millsp.].

AIMS: The aim of this study was to characterize a fungal endophyte Y3 from pigeon pea (Cajanus cajan [L.] Millsp), as a novel producer of vitexin, and its culture medium optimization and antioxidant activity. METHODS AND RESULTS: The endophyte from the leaves of pigeon pea was identified as Dichotomopilus funicola by the morphological and molecular characteristics. The most important medium variables affecting vitexin production in liquid culture of D. funicola Y3 were screened by Plackett-Burman design, and three culture medium constituents (i.e. l-phenylalanine, salicylic acid and CuSO4 ·5H2 O) were identified to play significant roles in vitexin production. The most significant factors were further optimized using by central composite design with response surface methodology. The DPPH radical-scavenging assay indicated that fungal vitexin exhibited notable antioxidant activity with an EC50 value of 164 µg l-1 . CONCLUSIONS: First, a novel endophyte vitexin-producing Dichotomopilus funicola Y3 was isolated from pigeon pea (Cajanus cajan[L.] Millsp.). The maximum vitexin yield was obtained as 78·86 mg l-1 under the optimum culture medium constituents: 0·06 g l-1  l-phenylalanine, 0·21 g l-1 salicylic acid, and 0·19 g l-1 CuSO4 ·5H2 O in medium, which is 4·59-fold higher than that in the unoptimized medium. Also, fungal vitexin clearly demonstrated its antioxidant potential. SIGNIFICANCE AND IMPACT OF THE STUDY: These findings provide an alternative source for large-scale production of vitexin by endophytic fungal fermentation and have a promising prospect in food and pharmaceutical industry.

New insights into mitogenomic phylogeny and copy number in eight indigenous sheep populations based on the ATP synthase and cytochrome c oxidase genes.

The origins and phylogeny of different sheep breeds has been widely studied using polymorphisms within the mitochondrial hypervariable region. However, little is known about the mitochondrial DNA (mtDNA) content and phylogeny based on mtDNA protein-coding genes. In this study, we assessed the phylogeny and copy number of the mtDNA in eight indigenous (population size, n=184) and three introduced (n=66) sheep breeds in China based on five mitochondrial coding genes (COX1, COX2, ATP8, ATP6 and COX3). The mean haplotype and nucleotide diversities were 0.944 and 0.00322, respectively. We identified a correlation between the lineages distribution and the genetic distance, whereby Valley-type Tibetan sheep had a closer genetic relationship with introduced breeds (Dorper, Poll Dorset and Suffolk) than with other indigenous breeds. Similarly, the Median-joining profile of haplotypes revealed the distribution of clusters according to genetic differences. Moreover, copy number analysis based on the five mitochondrial coding genes was affected by the genetic distance combining with genetic phylogeny; we also identified obvious non-synonymous mutations in ATP6 between the different levels of copy number expressions. These results imply that differences in mitogenomic compositions resulting from geographical separation lead to differences in mitochondrial function.

Methylation differences and expression profiles of the caprine DIO3 gene.

DIO3 gene encoding type 3 iodothyronine deiodinase is an imprinted gene, located in the DLK1-DIO3 (delta-like 1 homolog-type 3 iodothyronine deiodinase) imprinted domain, and is potentially involved in degrading excessive amounts of thyroid hormone to protect embryogenesis. However, the underlying regulatory mechanism of the imprinted DIO3 gene expression during fetal and neonatal development in goats has not been elucidated. In this study, we explored the DNA methylation patterns of the caprine DIO3 intragenic CpG island and quantified gene expression level in six tissues from Chinese Nanjiang Yellow 3-day old kids. The expression of the DIO3 gene was determined using quantitative reverse transcription-polymerase chain reactions (qRT-PCRs), while the identification of methylation patterns was determined using bisulfite-sequencing PCRs. Modest, and non-significant (P > 0.05), methylation patterns were noted for the DIO3 CpG island methylation in the brain, heart, liver, kidney, lung, and longissimus dorsi tissues (ranging from 26.48 to 34.92%). The expression level of the DIO3 mRNA was significantly higher (P < 0.05) in the liver tissue than in the other five tissues. Pearson's correlation analysis revealed that there was no significant relationship between methylation and gene expression (P > 0.05), which indicated that the expression of the caprine DIO3 gene was likely modified by other regulatory elements. This study identified DNA methylation and expression patterns of the DIO3 gene in goats and provided insights into further regulatory mechanisms of expression and imprinting in the DLK1-DIO3 domain.

Strong correlation between early stage atherosclerosis and electromechanical coupling of aorta.

Atherosclerosis is the underlying cause of cardiovascular diseases that are responsible for many deaths in the world, and the early diagnosis of atherosclerosis is highly desirable. The existing imaging methods, however, are not capable of detecting the early stage of atherosclerosis development due to their limited spatial resolution. Using piezoresponse force microscopy (PFM), we show that the piezoelectric response of an aortic wall increases as atherosclerosis advances, while the stiffness of the aorta shows a less evident correlation with atherosclerosis. Furthermore, we show that there is strong correlation between the coercive electric field necessary to switch the polarity of the artery and the development of atherosclerosis. Thus by measuring the electromechanical coupling of the aortic wall, it is possible to probe atherosclerosis at the early stage of its development, not only improving the spatial resolution by orders of magnitude, but also providing comprehensive quantitative information on the biomechanical properties of the artery.

Molecular cloning, characterization, and bioactivity analysis of interleukin 18 in giant panda (Ailuropoda melanoleuca).

Interleukin 18 (IL-18), as a member of IL-1 superfamily, is an important pleiotropic cytokine that modulates Th1 immune responses. In this report, we cloned and identified a homolog of IL-18 in giant panda (Ailuropoda melanoleuca) (designated as AmIL-18) from peripheral blood mononuclear cells stimulated with lipopolysaccharide. The open readin g frame of AmIL-18 cDNA is 579 bp encoding a deduced protein of 192 amino acids. AmIL-18 gDNA fragments contained 5 exons and 4 introns. The amino acid sequence of AmIL-18 shared 23.9 to 87.0% identity with other species. To evaluate the effects of AmIL-18 on the immune response, we expressed the recombinant AmIL-18 in Escherichia coli BL21 (DE3). The fusion protein PET-AmIL-18 was purified by nickel affinity column chromatography and verified by sodium dodecyl sulfate polyacrylamide gel electrophoresis and Western blot analysis. The biological function of purified PET-AmIL-18 was determined on mouse splenocytes by quantitative real-time polymerase chain reaction. INF-γ and other cytokines were increased when stimulated by PET-AmIL-18, particularly when combined with recombinant human interleukin 12, while a Th2-type cytokine, interleukin-4, was strikingly suppressed. These results will provide information for the potential use of recombinant proteins to manipulate the immune response in giant pandas and facilitate the study to protect this treasured species.

A feedback circuit between miR-133 and the ERK1/2 pathway involving an exquisite mechanism for regulating myoblast proliferation and differentiation.

MiR-133 was found to be specifically expressed in cardiac and skeletal muscle in previous studies. There are two members in the miR-133 family: miR-133a and miR-133b. Although previous studies indicated that miR-133a was related to myogenesis, the signaling pathways regulated by miR-133 were still not very clear. In this study, we showed that both miR-133a and miR-133b were upregulated during myogenesis through Solexa sequencing. We confirmed that miR-133 could promote myoblast differentiation and inhibit cell proliferation through the regulation of the extracellular signal-regulated kinase (ERK) signaling pathway in C2C12 cells. FGFR1 and PP2AC, which both participate in signal transduction of the ERK1/2 pathway, were found to be negatively regulated by miR-133a and miR-133b at the post-transcriptional level. Also, downregulation of ERK1/2 phosphorylation by miR-133 was detected. FGFR1 and PP2AC were also found to repress C2C12 differentiation by specific siRNAs. In addition, we found that inhibition of ERK1/2 pathway activity can inhibit C2C12 cell proliferation and promote the initiation of differentiation but form short and small myotubes. Furthermore, we found that the expression of miR-133 was negatively regulated by ERK1/2 signaling pathway. In summary, we demonstrated the role of miR-133 in myoblast and further revealed a new feedback loop between miR-133 and the ERK1/2 signaling pathway involving an exquisite mechanism for regulating myogenesis.

Structure and polymorphism of 16 novel Y-STRs in Chinese Han population.

Y-chromosome short tandem repeats (Y-STRs) are useful tools for identifying paternity origin and male-female mixed samples because of their male-specificity, haploid inheritance and relatively simplicity. We focused on novel Y-STRs deposited in the human Genome database from DYS708 to DYS726. We typed 16 male-specific Y-STRs from males of a Chinese Han population residing in Shanxi Province (north China), including DYS708-719, DYS721-723, and DYS726, but failed in typing DYS720, DYS724 and DYS725. The 16 Y-STRs, with mean gene diversity (GD) of 0.79, included three trinucleotide Y-STRs (711, 718, 719), nine tetranucleotide STRs (708, 709, 710, 712, 713, 715, 722, 723, 726) and four pentanucleotide repeat STRs (714, 716, 717, 721). DYS712, consisting of eight alleles, was the most informative STR in our population, with a GD of 0.843. The STRs were classified as simple STRs and complex STRs, according to their structures based on sequencing. Genetic indexes, including allele frequencies, haplotype distribution and male-specificity were determined. The Y-STRs, especially those male-specific, tetra- and penta-nucleotide, with only one copy on Y-chromosome, and relative simple structures, such as DYS709, DYS714, DYS715, DYS716, DYS718, DYS719, and DYS726, were suggested for the future forensic DNA analysis, while DYS724 and DYS725 were not recommended for their multi-copy distribution. The population data provided putative Y-STRs for future genetic and forensic applications.

Genetic variability and individual assignment of Chinese indigenous sheep populations (Ovis aries) using microsatellites.

The purpose of this study was to assess the genetic characteristics of six breeds of Chinese local sheep using 19 microsatellite loci and to effectively validate statistical methods for individual assignment based on informative microsatellites. All the six breeds deviated from Hardy-Weinberg equilibrium expectations, while the majority of markers complied. The polymorphism information content (PIC) of overall loci for the six populations ranged from 0.283 (SRCRSP5) to 0.852 (OarVH72). Tibetan sheep were the most diverse population with the highest mean allelic richness (6.895), while Ujmuqin (UQ) harboured the lowest allelic richness (6.000). The F-statistics for the six populations were F(IS) = -0.172, F(IT) = -0.082 and F(ST) = 0.077, respectively. Furthermore, the pair-wise F(IS) revealed a moderate genetic differentiation among populations (P < 0.01), indicating that all breeds can be considered genetically independent entities. The lowest genetic differentiation was between Tengchong (TC) and UQ (F(ST) = 0.041), and the highest one was between TC and Fat-tailed Han (F(ST) = 0.111). In comparing the three statistical models, we note that the seven microsatellite loci (MAF65, OarJMP58, SRCRSP9, MCM140, OarAE129, BM8125 and SRCRSP5) commonly used for individual assignment will ensure a powerful detection of individual origin, with accuracy up to 91.87%, when the likelihood-based method is used. Overall, these findings shed light onto the genetic characteristics of Chinese indigenous sheep and offer a set of microsatellite loci that is simple, economic and highly informative for individual assignment of Chinese sheep.

Three regulatory regions of the Aedes aegypti glutamine synthetase gene differentially regulate expression: identification of a crucial regulator in the first exon.

Aedes aegyptiglutamine synthetase (GS) is expressed constitutively at various developmental stages and its relative mRNA abundance increases in the midgut following blood feeding in support of the biosynthesis of chitin, a component of the peritrophic matrix. To understand the regulation of GS expression better, GS-luciferase reporter fusion genes were constructed and analysed in transiently transfected C6/36 cells. These studies have identified three GS regions: GS-A, -B and -C (C1, C2) that are required for efficient transcription. The crucial regulatory DNA sequence is located within 140 nucleotides of the GS-C region in the first exon. GS-B region between -209 and +4 contains a negative modulator that represses transcription of the GS-C promoter, but the 5'-GS-A region, between -476 and -282, can negate the transcription inhibition of GS-B and promote GS transcription of the GS-C promoter. Electrophoretic mobility shift assays showed that nuclear proteins for GS-A, GS-B and GS-C1 are present in the C6/36 cells, and therefore that GS-A, GS-B and GS-C1 indeed possess regulatory function. By contrast, nuclear proteins isolated from both cultured cells and midgut tissues bound to GS-C2, suggesting that GS-C2 plays an important role in GS transcription and that GS-C2 is regulated by several different and redundant transcription factors to achieve constitutive expression in a wide variety of tissues.

Differential regulation of ribosomal protein gene expression in Aedes aegypti mosquitoes before and after the blood meal.

In fat body of the mosquito, Aedes aegypti, a cycle of ribosome accumulation and degradation accompanies synthesis of the yolk protein precursor, vitellogenin. Here we compare the transcription and translation of ribosomal proteins rpS6, rpL8 and rpL34, relative to rRNA and vitellogenin genes in Aedes aegypti fat body after eclosion, and in response to a blood meal. Analysis using Northern blots and reverse-transcription polymerase chain reactions (RT-PCR) showed that the rpS6, rpL8 and rpL34 genes are coordinately regulated with respect to one another, and that ribosomal protein gene expression in this system was predominantly regulated by transcription during the 3-4 days between adult eclosion and blood feeding. After a blood meal, ribosomal protein mRNA levels remained similar to those in unfed females during the first 18 h, then declined to minimum levels by 48 h after the blood meal. These data indicate that transcription of ribosomal protein genes is low in vitellogenic mosquitoes, relative to previtellogenic females. Experiments with the dissected fat body, however, showed that levels of acetic acid-soluble proteins increased by approximately threefold between 12 and 24 h after the blood meal. Taken together, these observations suggest that the active translation of ribosomal proteins from stable mRNA accompanies ribosome biosynthesis after the blood meal. Thus, in the fat body of adult female mosquitoes, the expression of ribosomal protein genes is regulated at the level of transcription before the blood meal, while translational control is the predominant regulatory mechanism after the blood meal.

The ribosomal protein L34 gene from the mosquito, Aedes albopictus: exon-intron organization, copy number, and potential regulatory elements.

We describe the structural analysis of genomic DNA encoding ribosomal protein (rp) L34 from the mosquito, Aedes albopictus. Comparison of genomic DNA sequences encompassing approximately 8 kb with the rpL34 cDNA sequence showed that the gene contains three exons and two introns, encoding a primary transcript with a deduced size of 6196 nucleotides from the transcription start site to the polyadenylation site. Exon 1, which is not translated, measures only 45 bp, and is separated from Exon 2 by a 359 bp intron. Exon 2 measures 78 bp, and contains the AUG translation initiation codon 14 nucleotides downstream of its 5'-end. Downstream of Exon 2 is a 5270 bp intron, followed by the remainder of the coding sequence in Exon 3, which measures 444 bp including the polyadenylation signal. We used a novel PCR-based procedure to obtain 1.7 kb of DNA upstream of the rpL34 gene. Like the previously described Ae. albopictus rpL8 gene and various mammalian rp genes, the DNA immediately upstream of the rpL34 gene lacks the TATA box, and the rpL34 transcription initiation site is embedded in a characteristic polypyrimidine tract. The 5'-flanking DNA contained a number of cis-acting elements that potentially interact with transcription factors characterized by basic domains, zinc-coordinating DNA binding domains, helix-turn-helix motifs, and beta scaffold factors with minor groove contacts. Particularly striking was the conservation of an AP-4 binding site within 100 nucleotides upstream of the transcription initiation site in both Aal-rpL34 and Aal-rpL8 genes. Comparison of Southern hybridization signals using probes from the 5' and 3'-ends of the 5.3 kb second intron and the cDNA suggested that the Ae. albopictus rpL34 gene most likely occurs as a single expressed copy per haploid genome with restriction enzyme polymorphisms in the upstream flanking DNA and the likely presence of one or more pseudogenes.

Mosquito ribosomal protein rpL31 resembles rat rpL34: cDNA and deduced amino acid sequence.

An Aedes albopictus ribosomal protein rpL31 cDNA was sequenced, and found to encode a protein with homology to rat rpL34. The 544 bp mosquito cDNA contained an ATG start site, three in-frame termination codons, and an AATAAA polyadenylation signal. Mosquito rpL31 had a mass of 15,137 Da, a pI of 12.39 and contained 14.5% Arg and 14.5% Lys. PCR analyses with genomic DNA suggested the presence of a large intron near the 5'-end of the gene.

[DNA probe for identification of sibling species of Anopheles sinensis and Anopheles anthropophagus].

Genomic DNA libraries of Anopheles sinensis and Anopheles anthropophagus were constructed. The positive clones suitable for discrimination sibling species of An. sinensis and An. anthropophagus were screened and a clone from An. sinensis DNA library was selected and the insert DNA was used as a DNA probe to test dot blot of genomic DNA from An. sinensis and An. anthropophagus. The results showed that the DNA probe hybridized with all stages of An. sinensis DNA, but had very weak hybridization signal with An. anthropophagus DNA. The probe was very sensitive and could detect as little as 7.5ng An. sinensis which represents approximately one-150th part of the total DNA from single mosquito. The results demonstrated that the DNA probe reported here could be used to distinguish species of An.sinensis from An. anthropophagus.