Altered Growth Research Articles

Prenatal exposure to ambient air multi-pollutants significantly impairs intrauterine fetal development trajectory.

Impaired in utero fetal growth trajectory may have long term health consequences of the newborns and increase risk of adulthood metabolic diseases. Prenatal exposure to air pollution has been linked to fetal development restriction; however, the impact of exposure to ambient air pollutants on the entire course of intrauterine fetal development has not been comprehensively investigated. During 2015-2018, two cohorts of mother-infant dyads (N=678 and 227) were recruited in Shanghai China, from which three categories of data were systematically collected: (1) daily exposure to six air pollutants during pregnancy, (2) fetal biometry in the 2nd (gestational week 24, [GW24]) and 3rd trimester (GW36), and (3) neonatal outcomes at birth. We investigated the impact of prenatal exposure to air pollutant mixture on the trajectory of fetal development during the course of gestation, adjusting for a broad set of potential confounds. Prenatal exposure to PM2.5, PM10, SO2 and O3 significantly reduced fetal biometry at GW24, where SO2 had the most potent effect. For every 10 μg/m3 increment increase of daily SO2 exposure during the 1st trimester shortened femur length by 2.20mm (p=6.7E-21) translating to 5.3% reduction from the average of the study cohort. Prenatal air pollution exposure also decreased fetal biometry at GW36 with attenuated effect size. Comparing to the lowest exposed quartile, fetus in the highest exposed quartile had 6.3% (p=3.5E-5) and 2.1% (p=2.4E-3) lower estimated intrauterine weight in GW24 and GW36, respectively; however, no difference in birth weight was observed, indicating a rapid catch-up growth in the 3rd trimester. To our knowledge, for the first time, we demonstrated the impact of prenatal exposure to ambient air pollutants on the course of intrauterine fetal development. The altered growth trajectory and rapid catch-up growth in associated with high prenatal exposure may lead to long-term predisposition for adulthood metabolic disorders.

MON-LB001 Ovulation Induction Results in Altered Growth and Metabolic Dysfunction in Mice Offspring

Nearly 15% of couples are affected by infertility and a large proportion of individuals will need to use ovulation induction (OI) or assisted reproductive technologies (ARTs) to conceive. Previous studies have shown that offspring conceived by ARTs are predisposed towards increased insulin resistance and glucose intolerance. However, the long-term effects of OI alone on offspring health have not been studied. This rodent study was designed to elucidate the effects of maternal superovulation on offspring growth and development.C57Bl/6 females were either naturally mated (control= C) or super-ovulated (5 IU PMSG; 5IU hCG, OI group) and mated to C57Bl/6 males with one Agouti viable yellow (Avy) allelic mutation. The Avy allele contains an intracisternal A particle whose methylation levels determine expression of the agouti protein which alters coat color and can be used as a phenotypic readout for global methylation. Offspring (n= 108 control and n = 69 OI) were followed through 13 weeks of age to measure birth parameters, growth rate, fasting glucose, GTT, and body composition (EchoMRI). Parametric and non-parametric tests were used as indicated. Only results with p<0.05 are reported.Results: Surprisingly, while litter size was not different (C = 7, OI = 6), superovulated mothers had fewer surviving pups (C=6.5 pups, OI=5 pups). No major differences in coat color frequencies were observed between the two groups, suggesting no changes in DNA methylation. All OI pups had decreased anogenital distance (males C = 2.1mm, OI = 1.7mm; females C = 1.74mm, OI = 1.48mm), while OI female had lower birthweights (C = 1.38g and OI = 1.23g). Starting at four weeks of age, OI male had lower weight compared to control males. As early as 3 weeks, significant differences in fasting glucose levels were noted (C = 162 mg/dL, OI = 149.5mg/dL). Additionally, superovulated males had lower lean mass at 8 weeks of age (tested by EchoMRI: C = 23.6g, OI = 19.3g) and higher insulin levels at 13 weeks (120 min post injection, C = 339 mg/dL, OI = 213 mg/dL).In summary, we found that the process of OI alone has profound effects on offspring development in a sexual dimorphic fashion. Additional studies will be performed up to 30 weeks of age. Funding: R01 HD092267-01to P

The interactive effect of competition and climate on growth of boreal tree species in western Canada and Alaska

Understanding interactions between competition and climate in relation to their effects on individual tree growth is crucial to the development of climate-sensitive growth models required for modelling boreal forest succession in a changing climate. We used data from permanent growth and yield sample plots in western Canada and Alaska to investigate the impact of competition within a regional gradient of climatic conditions for lodgepole pine (Pinus contorta Douglas ex Loudon), jack pine (Pinus banksiana Lamb.), trembling aspen (Populus tremuloides Michx.), balsam poplar (Populus balsamifera L.), white spruce (Picea glauca (Moench) Voss), and black spruce (Picea mariana (Mill.) Britton, Sterns &amp; Poggenb.). We characterized the effects of competition (basal area of spruce–fir, deciduous, and pine trees larger than the focal tree) and climate (mean annual temperature and precipitation) and their interactions on basal area growth of individual trees using linear mixed-effects models. Our results indicated that intraspecific competition had stronger effects on growth than interspecific competition and climate. Moreover, significant interactions between intraspecific competition and climate suggest that an increase in intraspecific competition will lead to a reduction in tree growth for warmer regions (lodgepole pine, trembling aspen, balsam poplar, and white spruce) and wetter regions (jack pine). The manner in which interspecific competition altered tree growth responses to climate was variable, depending on tree species and competition type. These results indicate that the relationships between growth and climate may differ according to the degree of competition and the structure of the stand.

Gestational Diabetes Mellitus Is Associated with Age-Specific Alterations in Markers of Adiposity in Offspring: A Narrative Review.

Maternal hyperglycemia alters an offspring’s metabolic health outcomes, as demonstrated by the increased risk for obesity, impaired glucose handling and diabetes from early childhood onwards. Infant growth patterns are associated with childhood adiposity and metabolic health outcomes and, as such, can be used as potential markers to detect suboptimal metabolic development at an early age. Hence, we aimed to assess whether gestational diabetes mellitus (GDM) has an impact on offspring growth trajectories. Outcomes included weight gain (WG), body mass index (BMI), and skin fold thickness (SFT) measured at least at two time points from birth to later childhood. In addition, we explored the role of early life pre- and post-natal nutritional modifiable factors on longitudinal growth in infants of mother with GDM (GDM–F1). Despite the large heterogeneity of the studies, we can still conclude that GDM seems to be associated with altered growth outcomes in the offspring. More specifically, these alterations in growth outcomes seem to be rather time-specific. Increased SFT were reported particularly at birth, with limited information on reporting SFT between 2–5 y, and increased adiposity, measured via SFT and BMI, appeared mainly in later childhood (5–10 y). Studies evaluating longitudinal growth outcomes suggested a potential role of early life nutritional modifiable factors including maternal nutrition and breastfeeding. These may impact the cycle of adverse metabolic health by attenuating growth outcome alterations among GDM–F1. Conclusions: Timely diagnoses of growth deviations in infancy are crucial for early identification of GDM–F1 who are at risk for childhood overweight and metabolic disease development.

Genome-wide analysis of Jatropha curcas MADS-box gene family and functional characterization of the JcMADS40 gene in transgenic rice

BackgroundPhysic nut (Jatropha curcas), an inedible oilseed plant, is among the most promising alternative energy sources because of its high oil content, rapid growth and extensive adaptability. Proteins encoded by MADS-box family genes are important transcription factors participated in regulating plant growth, seed development and responses to abiotic stress. However, there has been no in-depth research on the MADS-box genes and their roles in physic nut.ResultsIn our study, 63 MADS-box genes (JcMADSs) were identified in the physic nut genome, and classed into five groups (MIKCC, Mα, Mβ, Mγ, MIKC*) according to phylogenetic comparison with Arabidopsis homologs. Expression profile analysis based on RNA-seq suggested that many JcMADS genes had the strongest expression in seeds, and seven of them responded in leaves to at least one abiotic stressor (drought and/or salinity) at one or more time points. Transient expression analysis and a transactivation assay indicated that JcMADS40 is a nucleus-localized transcriptional activator. Plants overexpressing JcMADS40 did not show altered plant growth, but the overexpressing plants did exhibit reductions in grain size, grain length, grain width, 1000-seed weight and yield per plant. Further data on the reduced grain size in JcMADS40-overexpressing plants supported the putative role of JcMADS genes in seed development.ConclusionsThis study will be useful in order to further understand the process of MADS-box genes involved in regulating growth and development in addition to their functions in abiotic stress resistance, and will eventually provide a theoretical basis for the functional investigation and the exploitation of candidate genes for the molecular improvement of physic nut.

Upregulation of Sortilin, a Lysosomal Sorting Receptor, Corresponds with Reduced Bioavailability of Latent TGFβ in Mucolipidosis II Cells.

Mucolipidosis II (ML-II) is a lysosomal disease caused by defects in the carbohydrate-dependent sorting of soluble hydrolases to lysosomes. Altered growth factor signaling has been identified as a contributor to the phenotypes associated with ML-II and other lysosomal disorders but an understanding of how these signaling pathways are affected is still emerging. Here, we investigated transforming growth factor beta 1 (TGFβ1) signaling in the context of ML-II patient fibroblasts, observing decreased TGFβ1 signaling that was accompanied by impaired TGFβ1-dependent wound closure. We found increased intracellular latent TGFβ1 complexes, caused by reduced secretion and stable localization in detergent-resistant lysosomes. Sortilin, a sorting receptor for hydrolases and TGFβ-related cytokines, was upregulated in ML-II fibroblasts as well as GNPTAB-null HeLa cells, suggesting a mechanism for inappropriate lysosomal targeting of TGFβ. Co-expression of sortilin and TGFβ in HeLa cells resulted in reduced TGFβ1 secretion. Elevated sortilin levels correlated with normal levels of cathepsin D in ML-II cells, consistent with a compensatory role for this receptor in lysosomal hydrolase targeting. Collectively, these data support a model whereby sortilin upregulation in cells with lysosomal storage maintains hydrolase sorting but suppresses TGFβ1 secretion through increased lysosomal delivery. These findings highlight an unexpected link between impaired lysosomal sorting and altered growth factor bioavailability.

Reproductive and energetic costs of injury in the mangrove tree crab

Nonlethal injury is a common and ubiquitous feature of marine systems and can result in altered growth and survival rates. Ecological theory predicts that injured animals should face an energetic tradeoff between investing in recovery vs. investing in reproduction. Possible impacts on reproduction may range in magnitude from very strong (elimination of reproduction), to intermediate (reduced number of offspring), to weak (reduced investment in each offspring). While this tradeoff is well established in terrestrial systems, it has received little attention in the marine environment, particularly in a way that quantitatively relates the degree of injury to the degree of reproductive impact. We examined injury via limb loss across 4 sites in the mangrove tree crab Aratus pisonii. We found that limb loss was highest at the site that was closest to roads and had the highest level of human presence, and conversely, injury was lowest at the site furthest from the road and with the lowest level of human presence. We found evidence that the quality of consumed food likely decreases with the number of limbs lost, but found no influence of limb loss on amount of food consumed or on energy storage. We show that limb loss reduced the number of eggs produced and that the mass of the ovary declined with the number of regenerating limbs, providing direct evidence for a tradeoff between reproduction and injury recovery. Further, our study therefore suggests that these impacts may increase with the level of human disturbance.

Modifications to Infant Formula Instructions Improve the Accuracy of Formula Dispensing.

Readability of infant formula preparation instructions is universally poor, which may result in inaccurate infant feeding. Given that inaccurate formula dispensing can lead to altered infant growth and increased adiposity, there is an increased need for easy to follow instructions for formula preparation. We hypothesize that altering infant formula instruction labels using feedback from iterative focus groups will improve the preparation accuracy of powdered infant formula in a randomized controlled trial. Participants were recruited from the community, 18 years of age or older, willing to disclose demographic information for focus group matching, and willing to participate freely in the first (n = 21) or second (n = 150) phase of the study. In the second phase, participants were randomized to use the standard manufacturer instructions or to use the modified instructions created in the first phase. Accuracy was defined as the percent error between manufacturer-intended powder formula quantity and the amount dispensed by the participant. Participants who were assigned to the modified instructions were able to dispense the powdered formula more accurately than participants who used the standard manufacturer instructions (−0.67 ± 0.76 vs. −4.66 ± 0.74% error; p < 0.0001). Accuracy in powdered formula dispensing was influenced by bottle size (p = 0.02) but not by body mass index (p = 0.17), education level (p = 0.75), income (p = 0.7), age (p = 0.89) or caregiver status (p = 0.18). Percent error of water measurement was not different between the groups (standard: −1.4 ± 0.6 vs. modified: 0.7 ± 0.6%; p = 0.38). Thus, caloric density was more accurate in the modified instructions group compared to the standard manufacturer instructions group (−0.3 ± 0.6 vs.−2.9 ± 0.9%; p = 0.03). Infant formula label modifications using focus group feedback increased infant formula preparation accuracy.

Hairy root transformation of Brassica rapa with bacterial halogenase genes and regeneration to adult plants to modify production of indolic compounds

During the last years halogenated compounds have drawn a lot of attention. Metabolites with one or more halogen atoms are often more active than their non-halogenated derivatives like indole-3-acetic acid (IAA) and 4-Cl-IAA. Within this work, bacterial flavin-dependent tryptophan halogenase genes were inserted into Brassica rapa ssp. pekinensis (Chinese cabbage) with the aim to produce novel halogenated indole compounds. It was investigated which tryptophan-derived indole metabolites, such as indole glucosinolates or potential degradation products can be synthesized by the transgenic root cultures. In vivo and in vitro activity of halogenases heterologously produced was shown and the production of chlorinated tryptophan in transgenic root lines was confirmed. Furthermore, chlorinated indole-3-acetonitrile (Cl-IAN) was detected. Other tryptophan-derived indole metabolites, such as IAA or indole glucosinolates were not found in the transgenic roots in a chlorinated form. The influence of altered growth conditions on the amount of produced chlorinated compounds was evaluated. We found an increase in Cl-IAN production at low temperatures (8 °C), but otherwise no significant changes were observed. Furthermore, we were able to regenerate the wild type and transgenic root cultures to adult plants, of which the latter still produced chlorinated metabolites. Therefore, we conclude that the genetic information had been stably integrated. The transgenic plants showed a slightly altered phenotype compared to plants grown from seeds since they also still expressed the rol genes. By this approach we were able to generate various stably transformed plant materials from which it was possible to isolate chlorinated tryptophan and Cl-IAN.

The response of Plasmodium falciparum to isoleucine withdrawal is dependent on the stage of progression through the intraerythrocytic cell cycle

BackgroundA previous study reported that the malaria parasite Plasmodium falciparum enters an altered growth state upon extracellular withdrawal of the essential amino acid isoleucine. Parasites slowed transit through the cell cycle when deprived of isoleucine prior to the onset of S-phase.MethodsThis project was undertaken to study at higher resolution, how isoleucine withdrawal affects parasite growth. Parasites were followed at regular intervals across an extended isoleucine deprivation time course across the cell cycle using flow cytometry.ResultsThese experiments revealed that isoleucine-deprived parasites never exit the cell cycle, but instead continuously grow at a markedly reduced pace. Moreover, slow growth occurs only if isoleucine is removed prior to the onset of schizogony. After S-phase commenced, the parasite is insensitive to isoleucine depletion and transits through the cell cycle at the normal pace.ConclusionsThe markedly different response of the parasite to isoleucine withdrawal before or after the onset of DNA replication is reminiscent of the nutrient-dependent G1 cell cycle checkpoints described in other organisms.

Long-term effects of in ovo exposure to an environmentally relevant dose of atrazine on the thyroid gland of Caiman latirostris

The increased incidence of human thyroid disorders, particularly in women, suggests that the exposure to endocrine-disrupting compounds (EDCs) together with sex-related factors could play a role in thyroid dysregulation. Since the herbicide atrazine (ATZ) is an environmental EDC suspected to behave as a thyroid disruptor, and Caiman latirostris is a crocodilian species highly sensitive to endocrine disruption that can be exposed to ATZ, this study aimed to describe the histoarchitecture and sexually dimorphic features of the thyroid gland of C. latirostris, and to determine the long-term effects of in ovo exposure to an environmentally relevant dose of ATZ (0.2 ppm) on its thyroid gland and growth. Control caimans showed no sexual dimorphisms. In contrast, ATZ-exposed caimans showed altered embryo growth but an unaltered temporal pattern of development and a sexually dimorphic response in the body condition index growth curves postnatally, which suggests a female-related increase in fat storage. Besides, both male and female exposed caimans showed increases in the size of the thyroid stromal compartment, content of interstitial collagen, and follicular hyperplasia, and decreases in the expression of androgen receptor in the follicular epithelium. ATZ-exposed females, but not males, also showed evidences of thyroid enlargement, colloid depletion, increased follicular epithelial height and increased presence of microfollicular structures. Our results demonstrate that prenatal exposure of caimans to ATZ causes thyroid disruption and that females were more vulnerable to ATZ than males. The effects were organizational and observed long after exposure ended. These findings alert on ATZ side-effects on the growth, metabolism, reproduction and development of non-target exposed organisms, particularly females.

Role of cystic fibrosis transmembrane conductance regulator in FHC colon epithelial cell dysfunction and colon cancer

ObjectiveTo determine the role of the cystic fibrosis transmembrane conductance regulator (CFTR) in colon cancer development, with a focus on cell migration, EGFR signaling, and inflammation using model FHC colon epithelial cells.BackgroundOur clinical observations indicate that individuals with cystic fibrosis (CF) over the age of 40 are 4–8 times more likely to get colon cancer than the general population. Moreover, the likelihood of getting colon cancer increases to over 30 times the general population’s risk in CF patients who have had an organ transplant. The mechanism(s) leading to increased colon cancer in CF patients is not fully understood, but dysfunctional Cl− and Na+ transport are highly implicated. Chronic inflammation has also been shown to play an important role in the development and progression of many cancers. We hypothesize that dysregulated ion transport in CF patients leads to chronic inflammation and increased incidence of colon cancer via altered epidermal growth factor receptor (EGFR) signaling.MethodsWe performed scratch assays on cultured human colon epithelial cells (FHC) and measured the rate of cell migration every 24 hours for 5 days in the presence of either CFTR activating or inhibiting compounds. EGFR signaling was analyzed using standard immunohistochemical labeling techniques and commercially available reagents in similarly treated FHC cells.ResultsCells treated with 500 μM IBMX and 5 μM forskolin (CFTR activators) had significantly decreased rates of cell migration (26 μm2/24 hours) compared to the control group (51 μm2/24 hours) n=3; p&lt;0.05. Control and colon cells treated with 500 μM IBMX and 5 μM forskolin showed low levels of EGFR labelling (restricted to cell periphery), whereas cells treated with 5 mM CFTR(inh)‐172 (CFTR inhibitor) showed more robust EGFR signal throughout the cytoplasm in 3 independent observations.ConclusionOur data indicates that suppressed CFTR activity impacts colon epithelial cell migration and EGFR localization in FHC cells. Additional research on CFTR and EGFR signaling is needed to better understand and improve treatment options for both colon cancer and CF patients.Support or Funding InformationFunding: NIH R01 HL137033‐01 awarded to MNH.

Brazilian Berry Extract, High‐Fat Diet and Prostate Cancer: In Vitro and In Vivo Evaluation of Inflammation and Extracellular Matrix

The high incidence of prostatic cancer (PCa) has encouraged studies in prostatic cellular biology all over the world. In addition, Brazilian berries, such as Myrciaria jaboticaba (Vell.) Berg, show a high polyphenol concentration in the peel, characterizing antioxidative and anti‐inflammatory properties. The aim herein was to analyze the anti‐inflammatory and remodeling tissue effects of the Jaboticaba peel extract (JPE), a patented product, in early prostatic adenocarcinoma development associated with high‐fat diet (HFD) intake, as well as to investigate the JPE role in human PCa and LNCaP cell lines. TRAMP mice from control groups received standard diet or HFD and the treated groups followed the same diet protocol plus JPE (5.8g/Kg/body weight during 5 days per week for 2 months). The dorsolateral prostate was collected for immunohistochemistry and Western Blotting analyses. PC‐3 and LNCaP cells were treated with different doses of JPE (125, 250, 500 ug/mL) and used for cellular viability assay and Western Blotting analyses. The results showed that the HFD intake led to an MMP‐9 increase and a Laminin protein level decrease, worsening the PCa profile in this transgenic model. Conversely, JPE led to decreased MMP‐9 and also TGF‐beta after HFD intake. Laminin level increased in both groups treated with JPE. Dose and time dependent JPE exposure reduced cellular viability, especially, in androgen‐responsive LNCaP cells. In addition, JPE induced NfkB and iNOS reduction not only in LNCaP but also in PC‐3 cell lines, suggesting that the growth inhibitory effect of JPE in PCa may be associated with its anti‐inflammatory role. To conclude, the tissue damage caused by HFD led to the deregulation of the extracellular matrix elements, which intensified cancer progression, compromising the epithelial‐stromal interaction in the dorsolateral prostate. However, JPE was beneficial for the dynamic interaction between the epithelium and stroma in vivo, and altered cancer cell growth by means of anti‐inflammatory pathway, pointing towards a possible adjuvant therapy for PCa delay, highlighting the natural compounds as an important strategy in prostatic disorders.Support or Funding InformationSao Paulo Research Foundation/FAPESP (2018 04579‐7). And Fund for Support to Teaching, Research and Outreach Activities FAEPEX/UNICAMP (2080/20)

Impact of diabetes, obesity and hypertension on preterm birth: Population-based study.

ObjectiveTo determine the impact of pre-pregnancy diabetes mellitus (D), obesity (O) and chronic hypertension (H) on preterm birth (PTB).MethodsRetrospective population-based cohort study in Ontario, Canada between 2012–2016. Women who had a singleton livebirth or stillbirth at > 20 weeks gestation were included in the cohort. Exposures of interest were D, O and H, individually, and in various combinations. The primary outcome was PTB at 241/7 to 366/7 weeks. PTB was further analyzed by spontaneous or provider-initiated, early (< 34 weeks) or late (34–37 weeks), and the co-presence of preeclampsia, large for gestational age (LGA), and small for gestational age (SGA). Multivariable Poisson regression models with robust error variance were used to generate relative risks (RR), further adjusted for maternal age and parity (aRR). Population attributable fractions (PAF) were calculated for each of the outcomes by exposure state.Results506,483 women were eligible for analysis. 30,139 pregnancies (6.0%) were complicated by PTB < 37 weeks, of which 7375 (24.5%) had D or O or H. Relative to women without D or O or H, the aRR for PTB < 37 weeks was higher for D (3.51; 95% CI 3.26–3.78) and H (3.81; 95% CI 3.55–4.10) than O (1.14; 95% CI 1.10–1.17). The combined state of DH was associated with a significantly higher aRR of PTB < 37 weeks (6.34; 95% CI 5.14–7.80) and < 34 weeks (aRR 10.33, 95% CI 6.96–15.33) than D alone. The risk of provider initiated PTB was generally higher than that for spontaneous PTB. Pre-pregnancy hypertension was associated with the highest risk for PTB with preeclampsia (aRR 45.42, 95% CI 39.69–51.99) and PTB with SGA (aRR 9.78, 95% CI 7.81–12.26) while pre-pregnancy diabetes was associated with increased risk for PTB with LGA (aRR 28.85, 95% CI 24.65–33.76).ConclusionCombinations of DOH significantly magnify the risk of PTB, especially provider initiated PTB, and PTB with altered fetal growth or preeclampsia.

Mutations in a Single Signaling Pathway Allow Cell Growth in Heavy Water.

Life is completely dependent on water. To analyze the role of water as a solvent in biology, we replaced water with heavy water (D2O) and investigated the biological effects by a wide range of techniques, using Schizosaccharomyces pombe as model organism. We show that high concentrations of D2O lead to altered glucose metabolism and growth retardation. After prolonged incubation in D2O, cells displayed gross morphological changes, thickened cell walls, and aberrant cytoskeletal organization. By transcriptomics and genetic screens, we show that the solvent replacement activates two signaling pathways: (1) the heat-shock response pathway and (2) the cell integrity pathway. Although the heat-shock response system upregulates various chaperones and other stress-relieving enzymes, we find that the activation of this pathway does not offer any fitness advantage to the cells under the solvent-replaced conditions. However, limiting the D2O-triggered activation of the cell integrity pathway allows cell growth when H2O is completely replaced with D2O. The isolated D2O-tolerant strains may aid biological production of deuterated biomolecules.

Altered Growth and Envelope Properties of Polylysogens Containing Bacteriophage Lambda N-cI- Prophages.

The bacterial virus lambda (λ) is a temperate bacteriophage that can lysogenize host Escherichia coli (E. coli) cells. Lysogeny requires λ repressor, the cI gene product, which shuts off transcription of the phage genome. The λ N protein, in contrast, is a transcriptional antiterminator, required for expression of the terminator-distal genes, and thus, λ N mutants are growth-defective. When E. coli is infected with a λ double mutant that is defective in both N and cI (i.e., λN-cI-), at high multiplicities of 50 or more, it forms polylysogens that contain 20–30 copies of the λN-cI- genome integrated in the E. coli chromosome. Early studies revealed that the polylysogens underwent “conversion” to long filamentous cells that form tiny colonies on agar. Here, we report a large set of altered biochemical properties associated with this conversion, documenting an overall degeneration of the bacterial envelope. These properties reverted back to those of nonlysogenic E. coli as the metastable polylysogen spontaneously lost the λN-cI- genomes, suggesting that conversion is a direct result of the multiple copies of the prophage. Preliminary attempts to identify lambda genes that may be responsible for conversion ruled out several candidates, implicating a potentially novel lambda function that awaits further studies.

Application sequence modulates microbiome composition, plant growth and apple replant disease control efficiency upon integration of anaerobic soil disinfestation and mustard seed meal amendment

Anaerobic soil disinfestation (ASD) and mustard seed meal (MSM) amendments can provide effective control of soil-borne diseases including apple replant disease. These measures rely on both chemical and biological modes of action to yield effective disease control and their integration may prove beneficial or, alternatively, deleterious to overall treatment efficiency when applied in concert. Potential outcomes of integrating ASD with MSM amendments were assessed by determining the effect of treatment application sequence and ASD carbon source on generation of allyl isothiocyanate (AITC) derived from Brassica juncea seed meal, structure of the rhizosphere and soil microbiome, control of apple replant pathogens, and plant growth. In bioassays conducted using ‘Gala’ apple seedlings, application of ASD or MSM treatments independently was as effective or superior to all integrated treatments for the control of replant pathogens. Application of ASD prior to MSM amendment diminished the yield of AITC attained in response to soil incorporation of the Brassica juncea:Sinapis alba seed meal. Treatment application sequence had significant effect on structure of the bulk soil fungal and bacterial community. Correspondingly, treatment application sequence significantly altered plant growth performance when orchard grass was utilized as the ASD carbon input. At harvest, rhizosphere fungal but not bacterial community composition was significantly altered in treated soil relative to the control, and sequence of treatment application had significant effect on rhizosphere fungal community structure. Failure of integrated treatments to enhance overall replant disease control may have resulted from many factors including reduced generation of active metabolites, diminished activity of mechanisms functional in pathogen suppression, or the elevated accumulation and retention of phytotoxic chemistries, the latter which would require extended plant back periods to circumvent. The findings indicate that under the experimental conditions employed, integration of ASD with MSM amendment is unlikely to yield additive or synergistic effects on apple replant disease control.

TUBB Variants Underlying Different Phenotypes Result in Altered Vesicle Trafficking and Microtubule Dynamics.

Tubulinopathies are rare neurological disorders caused by alterations in tubulin structure and function, giving rise to a wide range of brain abnormalities involving neuronal proliferation, migration, differentiation and axon guidance. TUBB is one of the ten β-tubulin encoding genes present in the human genome and is broadly expressed in the developing central nervous system and the skin. Mutations in TUBB are responsible for two distinct pathological conditions: the first is characterized by microcephaly and complex structural brain malformations and the second, also known as “circumferential skin creases Kunze type” (CSC-KT), is associated to neurological features, excess skin folding and growth retardation. We used a combination of immunocytochemical and cellular approaches to explore, on patients’ derived fibroblasts, the functional consequences of two TUBB variants: the novel mutation (p.N52S), associated with basal ganglia and cerebellar dysgenesis, and the previously reported variant (p.M73T), linked to microcephaly, corpus callosum agenesis and CSC-KT skin phenotype. Our results demonstrate that these variants impair microtubule (MT) function and dynamics. Most importantly, our studies show an altered epidermal growth factor (EGF) and transferrin (Tf) intracellular vesicle trafficking in both patients’ fibroblasts, suggesting a specific role of TUBB in MT-dependent vesicular transport.

Ectopic expression of a rice plasma membrane intrinsic protein (OsPIP1;3) promotes plant growth and water uptake.

Plasma membrane intrinsic proteins (PIPs) are known to be major facilitators of the movement of a number of substrates across cell membranes. From a drought-resistant cultivar of Oryza sativa (rice), we isolated an OsPIP1;3 gene single-nucleotide polymorphism (SNP) that is mostly expressed in rice roots and is strongly responsive to drought stress. Immunocytochemistry showed that OsPIP1;3 majorly accumulated on the proximal end of the endodermis and the cell surface around the xylem. Expression of GFP-OsPIP1;3 alone in Xenopus oocytes or rice protoplasts showed OsPIP1;3 mislocalization in the endoplasmic reticulum (ER)-like neighborhood, whereas co-expression of OsPIP2;2 recruited OsPIP1;3 to the plasma membrane and led to a significant enhancement of water permeability in oocytes. Moreover, reconstitution of 10×His-OsPIP1;3 in liposomes demonstrated water channel activity, as revealed by stopped-flow light scattering. Intriguingly, by patch-clamp technique, we detected significant NO3- conductance of OsPIP1;3 in mammalian cells. To investigate the physiological functions of OsPIP1;3, we ectopically expressed the OsPIP1;3 gene in Nicotiana benthamiana (tobacco). The transgenic tobacco plants exhibited higher photosynthesis rates, root hydraulic conductivity (Lpr ) and water-use efficiency, resulting in a greater biomass and a higher resistance to water deficit than the wild-type did. Further experiments suggested that heterologous expression of OsPIP1;3 in cyanobacterium altered bacterial growth under different conditions of CO2 gas supply. Overall, besides shedding light on the multiple functions played by OsPIP1;3, this work provides insights into the translational value of plant AQPs.

Disruption of Bone Zinc Metabolism during Postnatal Development of Rats after Early Life Exposure to Cadmium.

This current study was conducted to investigate whether bone tissue impairment induced by early life exposure to cadmium (Cd) during postnatal development could result from disruption to zinc (Zn) metabolism. For this reason, the offspring from mothers receiving either tap water, Cd, Zn or Cd + Zn during gestation and lactation periods were euthanized at PND21 and PND70. At the end of the lactation period (PND21), our results showed that exposure to Cd increased Cd accumulation and Zn depletion in the femur. Furthermore, calcium (Ca) level was reduced. At the molecular level, Cd induced an increase of MT-1 expression and caused an upregulation of ZIP2 accompanied with a down-regulation of ZnT5. Runx2, ALP, colα-1 and Oc mRNA levels were also decreased. In plasma, IGF-1 and osteocalcin concentrations were decreased. Further, Cd altered femoral growth by generating changes in the growth plate. Consequently, the toxic effect of Cd persisted at adult age (PND70) by decreasing bone volume (%BV/TV), bone mineral density (BMD) and Ca content and by increasing trabecular separation (Tb.Sp) in the distal femur. Interestingly, Zn supply provided total or partial corrections of several toxic effects of Cd. These data suggest that the increases of Zn bioavailability as well as the reduction of Cd accumulation in the femur following the changes in ZIP2 and ZnT5 expression are part of the mechanism involved in Zn protection against Cd toxicity on bone tissue.