Pip Gene Research Articles

Molecular Detection of Antibiotics Profile of Citrobacter freundii Isolated from Burn Infection

Fifty samples were taken for this study from burn victims receiving care at the Al-Hussien medical city between February and October 2021. In order to isolate Citrobacter freundii, two swabs were taken: one for culturing and the other for direct examination. Only12 (4.1%) of the 50 samples were isolated from burn and wound infections at the molecular level and 12 (4.1%) from culture. The results isolation and laboratory diagnosis as well as biochemical test approved that there is only 12 isolates belong to C.freundii confirmed by molecular detection by specific primers. Burn and wound is one of the rare causes of infection. Associated with sub sequent urinary tract infection and burn and wound infection. Three antibiotics were employed at the molecular level , the results showed that 10 samples were resistant to the (Tet b) gene, all samples were 100% sensitive to the PIP gene, and all samples (100% resistant to the erna gene).

Abstract PO3-14-01: Heterogeneity of tumor immune microenvironment to predict everolimus efficacy in premenopausal women with hormone receptor-positive/human epidermal growth factor receptor 2-negative adavanced breast cancer

Abstract Objective Everolimus (EVE), a mammalian target of rapamycin (mTOR) inhibitor, has been shown to prolong survival of patients with hormone receptor-positive/human epidermal growth factor receptor 2-negative (HR+/HER2-), advanced breast cancer (ABC) with endocrine resistance. Preclinical studies have suggested that mTOR is closely associated with the tumor immune microenvironment (TME). We aimed to explore the tumor heterogeneity of TME between patients with different response to everolimus (EVE), and identify potential markers to predict efficacy of EVE in premenopausal patients with HR+/HER2−, advanced breast cancer (ABC) suffering endocrine resistance. Methods Patients were divided into two groups according to the best response to EVE: the responsive subgroup (RS) and the non-responsive subgroup (NRS). Postoperative tumor tissue from patients who received EVE was collected for whole exome sequencing. Transcript abundance of 126 distinct tumor regions of interest (ROIs) were quantitated using digital spatial profiling, including 42 tumor cell zones (TCZs), 42 immune cell zones (ICZs), and 42 stroma cell zones (SCZs). Based on investigation in multiple discrete areas, differences in cell components, function and pathway, gene expression and immune cell infiltration between RS and NRS were investigated. Results Totally, 93 differentially expressed genes (DEGs) were identified in the ICZs, 174 DEGs in the TCZs, and 197 DEGs in the SCZs, using p< 0.05 and |log2FC >1| as the screening criterion. Among all the subgroup analyses on different ROIs, the statistical significance of PIP gene was the highest (ICZs: p=2.6E-12, TCZs: p=1.25E-20, SCZs: p=2.0E-18) in the comparison of RS and NRS. Moreover, we found that PIP was highly expressed in NRS and patients with a progression-free survival < 1 year. The receptor-legend analysis showed that, the intra-and inter-cellular communication in RS was mainly mediated by interaction between CCL-CCR family, while NRS mainly by COL family complex. Comparing all cell components extracted from each ROI, no statistical differences were found between RS and NRS, only a statistical trend in the SCZs (p=0.098). Further cell classification analysis showed fibroblasts highest in TCZs and SCZs, macrophages in ICZs. Compared to NRS, in TCZs, fibroblasts were significantly increased (p=0.01), and plasma cells (p=0.02) and neutrophils (p=0.03) were decreased in RS. In SCZs, the downregulated fibroblasts (p=0.04) and enhanced plasma cells (p=0.01) were observed in NRS. In ICZs, pDCs (p=0.048) and neutrophils (p=0.006) were significantly elevated in NRS compared with RS. Conclusion The utility of digital spatial gene expression profiling might provide some references to predict the efficacy of EVE in premenopausal patients with HR+/HER2- ABC with endocrine resistance. Citation Format: Yujing Tan, Fei Ma, Jiayu Wang, Pin Zhang, Binghe Xu, Liyan Xue, Ying Fan. Heterogeneity of tumor immune microenvironment to predict everolimus efficacy in premenopausal women with hormone receptor-positive/human epidermal growth factor receptor 2-negative adavanced breast cancer [abstract]. In: Proceedings of the 2023 San Antonio Breast Cancer Symposium; 2023 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2024;84(9 Suppl):Abstract nr PO3-14-01.

Effects of melatonin foliar application on hot pepper growth and stress tolerance

PurposeDrought and waterlogging are one of the most severe abiotic stresses towards plant growth and development. The experiment was implemented in the Isfahan University of Technology's research greenhouse to examine the effect of melatonin foliar spraying in hot pepper plants under waterlogging and drought stresses. MethodsThis factorial experiment was performed as a complete randomized design (CRD) in triplicate. The treatments included controls, waterlogging, drought stress, and melatonin foliar spraying at 0 and 500 µM concentrations. ResultsThe results demonstrated that the foliar melatonin spraying was more advantageous under drought and waterlogging stress conditions via increasing ammonium content, NR (nitrate reductase activity), chlorophyll content, proline, protein, transpiration, shoot length, root water content, amino acid alterations, and PIP gene expression. ConclusionsMelatonin influenced the hot pepper's growth by affecting enzyme activity NR hormonal changes (ABA), amino acid changes, and PIP gene expression.

Metagenomic insights into bacterial communities and functional genes associated with texture characteristics of Kazakh artisanal fermented milk Ayran in Xinjiang, China

The complex microflora of traditional fermented milk is crucial to milk coagulation mainly through acid and protease production; however, it is still unclear which microbes and proteases significantly influence the texture of Ayran, a Kazakh artisanal fermented milk in Xinjiang, China. In this study, fifty-nine samples of Ayran were collected and investigated on texture properties. Finally, six Ayran samples with different texture features were screened out, and the taxonomic and functional attributes of their microbiota were characterized by metagenomics. The results showed that the hardness of the fermented milk in Yili Kazakh Autonomous Prefecture was significantly higher than that in other pasture areas. Lactobacillus and Lactococcus were the core genera that affected the coagulation quality of milk. Furthermore, we found that the proline iminopeptidase pip (EC 3.4.11.5) gene of Lactobacillus helveticus and Limosilactobacillus fermentum and the dipeptidase E pepE (EC 3.4.13.21) gene of Lactococcus lactis were most associated with the coagulation quality of fermented milk. Furthermore, positive correlations were observed among the hardness of fermented milk, the activity of the proteases, and the corresponding functional gene expressions.

Generation of prolactin-inducible protein (Pip) knockout mice by CRISPR/Cas9-mediated gene engineering.

Prolactin-inducible protein (PIP) is a multifunctional glycoprotein that is highly expressed and found in the secretions of apocrine glands such as salivary, lacrimal, and sweat glands including the mammary glands. PIP has been implicated in various diseases, including breast cancer, gross cystic disease of the breast, keratoconus of the eye, and the autoimmune Sjögren's syndrome. Here we have generated a Pip knockout (KO) mouse using the Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR)/CRSPR-associated (Cas)9 system. The Cas9 protein and two single guide RNAs targeting specific regions for both exons 1 and 2 of the Pip gene were microinjected into mouse embryos. The deletions and insertions promoted by CRISPR/Cas9 system on the Pip gene successfully disrupted Pip protein coding, as confirmed by PCR genotyping, sequencing, and ultimately Western blot analysis. This mouse model was generated in the inbred C57Bl/6J mouse, which exhibits lower genetic variation. This novel CRISPR Pip KO mouse model will not only be useful for future studies to interrogate the multifunctional role of PIP in physiological processes but will facilitate a broader understanding of the function of PIP in vivo while providing unprecedented insight into its role in a spectrum of diseases attributed to the deregulation of the PIP gene.

A TetR/AcrR family regulator pip induces phenazine biosynthesis but represses pyrrolnitrin biosynthesis in biocontrol agent Pseudomonas chlororaphis G05

Pseudomonas chlororaphis G05 produces both phenazine-1-carboxylic acid as well as pyrrolnitrin. Both metabolites play a key role in inhibiting some phytopathogenic fungi growth and bioprotecting plants against some diseases in modern agriculture. Though a few regulatory genes critical for pyrrolnitrin production were identified, the regulatory pathways involving pyrrolnitrin biosynthesis were not well understood. By employing random transposon mutagenesis, we isolated a dark blue colony G05D02 in which a pip gene was identified to be disrupted with the insertion of a transposon mini-Tn5Kan. Like in other Pseudomonas spp., Pip positively activates phenazine production in P. chlororaphis G05, but Pip may act as a repressor for pyrrolnitrin biosynthesis in our isolate. To verify its regulatory function, we constructed the pip-negative mutants, G05Δpip, G05Δphz::lacZΔpip and G05Δprn::lacZΔpip. By quantifying β-galactosidase activity, we found that absence of pip dramatically upregulates the prn operon expression. With quantification of pyrrolnitrin produced by the mutant G05Δpip, moreover, we confirmed that Pip deficiency caused remarkable increase of pyrrolnitrin production. As expected, phenazine-1-carboxylic acid biosynthesized by the mutant G05Δpip was much less than that in the wild-type strain. Further analysis of fusion constructs and RT-qPCRs also confirmed these results. Taken together, Pip induces phenazine-1-carboxylic acid production but represses pyrrolnitrin production in P. chlororaphis G05.

A novel piperidine degradation mechanism in a newly isolated piperidine degrader Pseudomonas sp. strain KU43P.

The degradation pathways in microorganisms for piperidine, a secondary amine with various applications, are not yet fully understood, especially in non-Mycobacterium species. In this study, we have identified a piperidine-degrading isolate (KU43P) from a soil sample collected in a cultivation field in Osaka, Japan, and characterized its mechanisms of piperidine degradation, thereby furthering current understanding of the process. The genome of isolate KU43P consists of a 5,869,691-bp circular chromosome with 62.67% GC content and with 5,294 predicted protein-coding genes, 77 tRNA genes, and 22 rRNA genes. 16S rRNA gene sequence analysis and average nucleotide identity analysis suggest that the isolate is a novel species of the Pseudomonas putida group in the genus Pseudomonas. The genomic region encoding the piperidine degradation pathway, designated as the pip gene cluster, was identified using transposon mutagenesis and reverse transcription polymerase chain reaction. Deletion analyses of pipA, which encodes a glutamine synthetase (GS)-like protein, and pipBa, which encodes a cytochrome P450 monooxygenase, indicate that pipA and pipBa are involved in piperidine metabolism and suggest that pipA is involved in the first step of the piperidine metabolic pathway. Escherichia coli whole cells overexpressing PipA converted piperidine and glutamate to γ-glutamylpiperidide, and crude cell extract enzyme assays of PipA showed that this reaction requires ATP and Mg2+. These results clearly show that pipA encodes γ-glutamylpiperidide synthetase and that piperidine is first glutamylated and then hydroxylated in the piperidine degradation pathway of Pseudomonas sp. strain KU43P. This study has filled a void in the general knowledge of the microbial degradation of amine compounds.

Changes in plasma membrane aquaporin gene expression under osmotic stress and blue light in tomato

Divergent abiotic stresses induce osmotic stress on plant cells resulting in an imbalance in water homeostasis which is preserved by aquaporins. Since the plasma membrane aquaporins (PIPs) were shown to be involved in seed development and responses to abiotic stresses, we focused on determining the contribution of mannitol-induced osmotic stress, blue light (BL), and 7B-1 mutation to their gene expression in tomato (Solanum lycopersicum L.) seeds. To assess that, we used a quantitative RT-PCR to determine the expression profiles of genes encoding PIPs. Subsequently, a multiple linear regression analysis was used to evaluate the impact of studied stressors (mannitol and BL) and 7B-1 mutation on PIP gene expressions. We found that mannitol-induced osmotic stress and 7B-1 mutation (conferring the lower responsiveness to osmotic stress- and BL-induced inhibition of seed germination) decreased expression of PIP1;3, PIP2;3 and PIP1;2, PIP2;1 genes, respectively. This might be a way to retain water for radicle elongation and seed germination under the stress conditions. Interestingly, the expression of PIP1;3 gene was downregulated not only by osmotic stress, but also by BL. Altogether, our data indicate the existence of a link between osmotic stress and BL signalling and the involvement of the 7B-1 mutation in this crosstalk.

Effect of Rhizophagus irregularis on osmotic adjustment, antioxidation and aquaporin PIP genes expression of Populus × canadensis ‘Neva’ under drought stress

Drought is an abiotic stress that severely reduces plant growth. Responding to drought, plants would induce a series of physiological and biochemical changes. Colonization by arbuscular mycorrhizal (AM) fungi was reported beneficial in improving plants’ drought tolerance. However, the effect of AM fungi in improving drought tolerance of widely planted Populus spp. was rarely reported. The effect of AM fungus (Rhizophagus irregularis) on malondialdehyde (MDA) content, proline and soluble proteins content, antioxidative enzymes activates, relative water content (RWC) and water use efficiency (WUE), and the aquaporin PIP genes expression of Populus × canadensis ‘Neva’ leaves under well-watered and drought-stressed condition was evaluated. R. irregularis could colonize more than 80 % of poplar roots, reduce MDA and proline content, lower antioxidative enzymes activates, and down-regulate the expression of PIP2;1, PIP2;2. Meanwhile, R. irregularis could increase soluble protein content, increase RWC and WUE, and up-regulate the expression of PIP1;1, PIP1;3, PIP1;4, PIP1;5, PIP2;1, PIP2;2, and PIP2;3. In conclusion, R. irregularis could improve drought tolerance of P. canadensis by increasing RWC via regulation of aquaporin genes expression, and consequently increased WUE, lowered accumulation of osmotic adjustment molecule, reduced ROS accumulation and oxidative damage. Further studies focusing on the influence of AM fungi on specific aquaporin PIP gene location, function and expression in plant responding to drought stress are needed.

Cell-Specific Cre Strains For Genetic Manipulation in Salivary Glands.

The secretory acinar cells of the salivary gland are essential for saliva secretion, but are also the cell type preferentially lost following radiation treatment for head and neck cancer. The source of replacement acinar cells is currently a matter of debate. There is evidence for the presence of adult stem cells located within specific ductal regions of the salivary glands, but our laboratory recently demonstrated that differentiated acinar cells are maintained without significant stem cell contribution. To enable further investigation of salivary gland cell lineages and their origins, we generated three cell-specific Cre driver mouse strains. For genetic manipulation in acinar cells, an inducible Cre recombinase (Cre-ER) was targeted to the prolactin-induced protein (Pip) gene locus. Targeting of the Dcpp1 gene, encoding demilune cell and parotid protein, labels intercalated duct cells, a putative site of salivary gland stem cells, and serous demilune cells of the sublingual gland. Duct cell-specific Cre expression was attempted by targeting the inducible Cre to the Tcfcp2l1 gene locus. Using the R26Tomato Red reporter mouse, we demonstrate that these strains direct inducible, cell-specific expression. Genetic tracing of acinar cells using PipGCE supports the recent finding that differentiated acinar cells clonally expand. Moreover, tracing of intercalated duct cells expressing DcppGCE confirms evidence of duct cell proliferation, but further analysis is required to establish that renewal of secretory acinar cells is dependent on stem cells within these ducts.

Effects of exogenous 5-aminolevulinic acid on photosynthesis, stomatal conductance, transpiration rate, and PIP gene expression of tomato seedlings subject to salinity stress.

The effects of exogenous 5-aminolevulinic acid (ALA) on photosynthesis, plant growth, and the expression of two aquaporin genes in tomato seedlings under control and salinity conditions were investigated. Exogenous ALA application significantly improved net photosynthetic rate (Pn), total chlorophyll content, and plant biomass accumulation of tomato seedlings under salinity stress. As revealed by real-time PCR analyses, after treatment with ALA alone, expression of both LePIP1 and LePIP2 in the two tomato cultivars was up-regulated at 2 h and subsequently decreased to normal levels. Under salinity stress, transcript levels of LePIP1 in both leaves and roots of salt-sensitive cultivars (cv. Zhongza No.9) increased significantly and were considerably higher than in cultivars exposed to ALA alone. In contrast, the expression levels of LePIP1 and LePIP2 in cvs. Jinpeng No.1 cultivars were slightly lower under salinity stress than under ALA treatment. In addition, transcript levels of both LePIP1 and LePIP2 in the roots of Jinpeng No. 1 cultivars were considerably lower than those in the roots of Zhongza No. 9 cultivars under salinity stress, regardless of ALA supplementation, implying that Jinpeng No. 1 cultivars had a better capacity to maintain membrane intrinsic protein stability. Further, ALA application distinctly counteracted the up- or down-regulation of LePIP1 and LePIP2 in both cultivars under salinity stress, in accordance with the improvements instomatal conductance, transpiration rate, and Pn of tomato leaves. The results presented here indicate that ALA controls aquaporin expression, thus, presumably ALA regulates water homeostasis and enhances salt tolerance of tomato seedlings.

The calcium-dependent protein kinase CPK7 acts on root hydraulic conductivity.

The hydraulic conductivity of plant roots (Lp(r)) is determined in large part by the activity of aquaporins. Mechanisms occurring at the post-translational level, in particular phosphorylation of aquaporins of the plasma membrane intrinsic protein 2 (PIP2) subfamily, are thought to be of critical importance for regulating root water transport. However, knowledge of protein kinases and phosphatases acting on aquaporin function is still scarce. In the present work, we investigated the Lp(r) of knockout Arabidopsis plants for four Ca(2+)-dependent protein kinases. cpk7 plants showed a 30% increase in Lp(r) because of a higher aquaporin activity. A quantitative proteomic analysis of wild-type and cpk7 plants revealed that PIP gene expression and PIP protein quantity were not correlated and that CPK7 has no effect on PIP2 phosphorylation. In contrast, CPK7 exerts a negative control on the cellular abundance of PIP1s, which likely accounts for the higher Lp(r) of cpk7. In addition, this study revealed that the cellular amount of a few additional proteins including membrane transporters is controlled by CPK7. The overall work provides evidence for CPK7-dependent stability of specific membrane proteins.

The inter‐kingdom solo OryR regulator of Xanthomonas oryzae is important for motility

The LuxR-type transcriptional regulator OryR of the rice pathogen Xanthomonas oryzae pv. oryzae (Xoo) is a member of a subgroup of regulators found in plant-associated bacteria that are known to respond to plant signals. OryR has been shown previously to positively regulate the neighbouring pip gene and to be important for rice virulence. The role of this inter-kingdom signalling regulator was investigated through a genome-wide transcriptome analysis. OryR was found to positively regulate 220 genes, whereas 110 were down-regulated. A significant over-representation of movement-related genes among the positively regulated ones was found, including 30 flagellar genes, accounting for 14% of the up-regulated genes above the two-fold cut-off value. In Xoo, both swimming and swarming respond to rice macerate and OryR plays a role in the induction of both of these types of motility under these conditions. In this study, we have also shown that the flagellar regulator flhF contains a lux box-like element in its promoter region, similar to the oryR-regulated neighbouring pip gene; via the use of a transcriptional fusion reporter, it was shown that flhF is regulated by OryR. Finally, the role of OryR in motility was also demonstrated by the significant reduction in flagellin content in the oryR Xoo mutant with respect to the wild-type, as observed by in planta proteomics studies.

Influence of salinity on pip gene expression in citrus roots and its relationship with root hydraulic conductance, transpiration and chloride exclusion from leaves

The present work studies the effect of salinity on PIP aquaporins gene expression in citrus roots and its relationship with root hydraulic conductance (Kr), transpiration rate (E) and chloride transport to leaves. To this end, ten-month-old seedlings of Cleopatra mandarin (CM), Carrizo citrange (CC) and Poncirus trifoliata (PT) were tested.No effect was detected of salt treatments on PIP1 and PIP2 aquaporin mRNA transcript abundances from citrus roots, although PIP1 expression in CM roots was lower than in CC and PT.The lowest Kr and E values were detected in CM, whereas PT had the highest. CC seedlings presented intermediate values for these parameters. Addition of HgCl2 to either control or salt solution (200mM NaCl) led to a decrease in Kr and E, thus implying aquaporin involvement. By contrast, salinity strongly reduced Kr and E in all plants, with this effect being unrelated to aquaporin activity.In salinized seedlings, E values appear to be related with Cl− concentration in leaves. Thus, CM seedlings treated with 80mM NaCl presented a lower Cl− uptake by leaves than PT, whereas this trend was intermediate in CC. Moreover, Hg2+ treatments significantly reduced leaf Cl− concentration in salt stressed plants, probably through the reduction of E.We can conclude that differences among genotypes in PIP1 expression affect Cl− exclusion from leaves, probably due to effects on water movement. Nevertheless, long-term salt treatments did not affect PIP expression in citrus plants, but reduced root hydraulic conductance and transpiration.

Isolation of conditional expression mutants in Mycobacterium tuberculosis by transposon mutagenesis

In Mycobacterium tuberculosis identification of essential genes has been hampered by the scarcity of suitable genetic tools for genome wide screenings. We constructed two Himar1 transposon derivatives in which the Streptomyces pristinamycin I-inducible ptr promoter was inserted at one transposon end in outward orientation. These transposons, Tn-pip/pptr (which harbours the promoter and its repressor pip gene) and Tn-pptr (which depends on a host expressing the pip gene), were inserted in the thermosensitive mycobacteriophage phAE87. After transduction into M. tuberculosis H37Rv, hygromycin resistant clones were selected in the presence of pristinamycin, screened for inducer dependent growth, and the transposon insertion point mapped by sequencing. Out of 3530 Hyg(R) mutants tested, we obtained 14 (0.4%) single insertion conditional mutants. In three (leuA, mazE6, rne) pptr was located upstream of genes whose function had been assessed by experimental evidence, whereas in seven the transposon targeted genes (ftsK, glf, infB, metC, pyrD, secY, and tuf) whose function had been assigned by similarity with homologous genes and four ORFs of unknown function (Rv0883c, Rv1478, Rv2050 and Rv2204c). These results validate our mutagenesis system and provide previously unavailable conditional expression mutants in genes of known, putative and unknown functions for genetic and physiological studies.

Water-deficit tolerance in citrus is mediated by the down regulation of PIP gene expression in the roots

Water deficit (WD) is a growing problem in agriculture. In citrus crops, genetically-determined rootstock characteristics are important factors influencing plant responses to WD. Aquaporins are involved in regulating the water supply to the plant by mediating water flow through the cell membranes. Recent studies support a direct role for aquaporins in plant water relations and demonstrate their involvement in WD tolerance. This study investigates the relationship between photosynthetic and water-balance parameters with aquaporin expression levels and hydraulic conductance of roots (Kr) in conditions of moderate WD in citrus rootstocks. The plant materials used were the rootstocks Poncirus trifoliata (L.) Raf. (PT), Cleopatra mandarin (Citrus reshni Hort ex Tan.) (CM) and 030115 (a hybrid of the two former rootstocks), all grafted with the citrus variety ‘Valencia Late’ (C. sinensis (L.) Osb). Plants were irrigated with two differents irrigation doses (normal irrigation and moderate WD) during 70 days and leaf water potential (ψs), net CO2 assimilation (ACO2), transpiration, stomatal conductance (gs) and substomatal CO2 concentration (Ci) were measured periodically under both irrigation conditions. Kr and PIP1 and PIP2 gene expression levels in fine roots of control plants and plants subjected to WD on day 43 of the experiment were determined. Under WD conditions, the hybrid 030115 drastically reduced aquaporin expression and Kr, accompanied by a loss of plant vigour but without reducing the net CO2 assimilation (ACO2). PT maintained the same aquaporin expression level and similar Kr under WD as under normal irrigation conditions, but suffered a sharp reduction in ACO2. CM, which has lower Kr and aquaporin expression than PT under both normal irrigation conditions and WD, responded better to water stress conditions than PT. Low aquaporin levels, or down-regulated aquaporin expression, accompanied by decreased plant vigour led to decreased plasma membrane permeability, thereby facilitating water retention in the cells under water stress conditions. This may induce water stress tolerance in citrus rootstocks.

Patterns of PIP gene expression in Populus trichocarpa during recovery from xylem embolism suggest a major role for the PIP1 aquaporin subfamily as moderators of refilling process

Embolism and the refilling of xylem vessels are intrinsic to the ability of plants to handle the transport of water under tension. Although the formation of an embolized vessel is an abiotic process, refilling against the pressure gradient requires biological activity to provide both the energy and the water needed to restore xylem transport capacity. Here, we present an analysis of the dynamics of embolism and refilling in Populus trichocarpa and follow temporal dynamics of co-occurring changes in expression level of aquaporins. Under mesic conditions, we found that the percent loss of conductance (PLC) varied diurnally by as much as 20%, suggesting a continuous embolism/refilling cycle. An increase in water stress tilted the balance between the two processes and increased the PLC to as much as 80%. Subsequent re-watering resulted in the reversal of water stress and recovery of PLC to pre-stress levels. Stem parenchyma cells responded to drought stress with considerable up-regulation of the PIP1 subfamily of water channels but not the PIP2 subfamily. Even more significant was the finding that PoptrPIP1.1 and PoptrPIP1.3 genes were up-regulated in response to embolism, but not to water stress, and were down-regulated after embolism removal, suggesting a local ability of plants to sense an embolism presence.

Aquaporins in the wild: natural genetic diversity and selective pressure in the PIP gene family in five Neotropical tree species.

BackgroundTropical trees undergo severe stress through seasonal drought and flooding, and the ability of these species to respond may be a major factor in their survival in tropical ecosystems, particularly in relation to global climate change. Aquaporins are involved in the regulation of water flow and have been shown to be involved in drought response; they may therefore play a major adaptive role in these species. We describe genetic diversity in the PIP sub-family of the widespread gene family of Aquaporins in five Neotropical tree species covering four botanical families.ResultsPIP Aquaporin subfamily genes were isolated, and their DNA sequence polymorphisms characterised in natural populations. Sequence data were analysed with statistical tests of standard neutral equilibrium and demographic scenarios simulated to compare with the observed results. Chloroplast SSRs were also used to test demographic transitions. Most gene fragments are highly polymorphic and display signatures of balancing selection or bottlenecks; chloroplast SSR markers have significant statistics that do not conform to expectations for population bottlenecks. Although not incompatible with a purely demographic scenario, the combination of all tests tends to favour a selective interpretation of extant gene diversity.ConclusionsTropical tree PIP genes may generally undergo balancing selection, which may maintain high levels of genetic diversity at these loci. Genetic variation at PIP genes may represent a response to variable environmental conditions.

522 PROLACTIN-INDUCED PROTEIN (PIP) GENE IS POSSIBLY ASSOCIATED WITH THE PREPUCE DEVELOPMENT OF HYPOSPADIAS

You have accessJournal of UrologyPediatrics: Congenital Anomalies - Lower Urinary Tract & Genitalia1 Apr 2010522 PROLACTIN-INDUCED PROTEIN (PIP) GENE IS POSSIBLY ASSOCIATED WITH THE PREPUCE DEVELOPMENT OF HYPOSPADIAS Satoshi Kurokawa, Yoshiyuki Kojima, Kentaro Mizuno, Hideyuki Kamisawa, Akihiro Nakane, Yutaro Hayashi, and Kenjiro Kohri Satoshi KurokawaSatoshi Kurokawa More articles by this author , Yoshiyuki KojimaYoshiyuki Kojima More articles by this author , Kentaro MizunoKentaro Mizuno More articles by this author , Hideyuki KamisawaHideyuki Kamisawa More articles by this author , Akihiro NakaneAkihiro Nakane More articles by this author , Yutaro HayashiYutaro Hayashi More articles by this author , and Kenjiro KohriKenjiro Kohri More articles by this author View All Author Informationhttps://doi.org/10.1016/j.juro.2010.02.721AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookTwitterLinked InEmail INTRODUCTION AND OBJECTIVES We have developed a rat model of hypospadias by exposure to flutamide in utero. This rat model showed proximal hypospadias in 100 % of offspring following maternal exposure to flutamide. We investigated the molecular mechanisms in the development of hypospadias at the critical period. We tried to identify genes that were down-regulated in hypospadiac tissue compared to control tissue. Genes may exist that have crucial roles in the development of hypospadias. We identified the Prolactin-induced protein (Pip) gene that may be especially associated with preputial development. METHODS Timed pregnant SD rats were administered 7.5 mg of flutamide or 1.5 ml of control vehicle by intraperitoneal injection from gestational days 15 to 17. Dams were sacrificed on gestational day 17, and the genital tubercles (GT) of male pups were harvested. Pip gene expression of extracted RNA was analyzed by quantitative RT-PCR and the distributions of Pip protein were examined histologically. Prepuces harvested from hypospadiac patients and buried penis patients (as a control) were used to analyze the Pip expression and distribution by quantitative RT-PCR and immunohistochemistry respectively. RESULTS The mRNA level of Pip was significantly lower in the hypospadiac GT than normal GT, and the Pip protein was locally expressed on the prepuce of GTs. The mRNA level of Pip was not significantly different in the prepuce of hypospadiac patients from that of control patients, but Pip was locally expressed on the prepuce of GTs. CONCLUSIONS To determine the hypospadiac development, it might be useful to investigate each aspect of three penile anormalies; an abnormal ventral opening of the urethral meatus, an abnormal ventral curvature of the penis and an abnormal distribution of prepuce. Pip, lower-expressed in the hypospadiac GT, may be associated with the prepuce development. The timing of harvesting prepuce from patients was different from the critical period of hypospadias development. This is one of the reasons why Pip gene expression was not different between the hypospadiac patients and the controls. Pip could be correlated with the abnormal development of hypospadiac prepuce. Nagoya, Japan© 2010 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 183Issue 4SApril 2010Page: e206 Advertisement Copyright & Permissions© 2010 by American Urological Association Education and Research, Inc.MetricsAuthor Information Satoshi Kurokawa More articles by this author Yoshiyuki Kojima More articles by this author Kentaro Mizuno More articles by this author Hideyuki Kamisawa More articles by this author Akihiro Nakane More articles by this author Yutaro Hayashi More articles by this author Kenjiro Kohri More articles by this author Expand All Advertisement Advertisement PDF downloadLoading ...

Prevalence, phenotypic and genetic characteristics of prolyliminopeptidase‐negative Neisseria gonorrhoeae isolates in Sweden during 2000–2007

In Neisseria gonorrhoeae culture diagnostics, species confirmation is commonly performed using commercial biochemical tests relying on prolyliminopeptidase (PIP) activity. It was previously shown that one PIP-negative strain was mainly globally transmitted during 2000-2004. The aims were to investigate the prevalence and phenotypic and genetic characteristics of PIP-negative N. gonorrhoeae isolates in Sweden during 2000-2007. Gonococcal isolates (n = 1230) cultured in Sweden during 2000-2007 were characterized using PIP screening, antibiogram, serovar determination, pip and porB gene sequencing, and N. gonorrhoeae multiantigen sequence typing (NG-MAST). Fifteen (1.2%) of the isolates were PIP-negative. Of those, 13 (87%) were indistinguishable to the previously described globally transmitted strain, i.e. displayed serovar IB-4 (Bpyvut), similar antibiograms, ST210 (n = 10)/ST292 (n = 3) and contained an identical single nucleotide pip gene deletion. Wherever high reliance is placed on PIP activity for N. gonorrhoeae species confirmation, changes in the diagnostic strategies may need to be considered and/or monitoring of the PIP activity is crucial.