CRISPR/Cas9-mediated lipoxygenase gene-editing in yellow pea leads to major changes in fatty acid and flavor profiles

Introduction

Although pulses are nutritious foods containing high amounts of protein, fiber and phytochemicals, their consumption and use in the food industry have been limited due to the formation of unappealing flavors/aromas described as beany, green, and grassy. Lipoxygenase (LOX) enzymes are prevalent among pulse seeds, and their activity can lead to the formation of specific volatile organic compounds (VOCs) from certain polyunsaturated fatty acids (PUFAs). As a widespread issue in legumes, including soybean, these VOCs have been linked to certain unappealing taste perception of foods containing processed pulse seeds.

Methods

To address this problem in pea and as proof of principle to promote the wider use of pulses, a Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR) construct was designed to create null alleles (knockouts) of PsLOX2 which had been implicated in the generation of VOCs in peas.

Results and discussion

Successful CRISPR/Cas9-mediated LOX gene editing of stable transgenic pea lines (TGP) was confirmed by DNA sequencing of the wild type (WT) and TGP pslox2 mutant lines. These lines were also assessed for LOX activity, PUFA levels, and VOCs. Compared to WT peas, the TGP lines showed a significant reduction (p < 0.05) in LOX activity and in the concentration of key VOCs, including hexanal, 2-hexenal, heptanal, (E)-2-heptenal, (E,E)-2,4-heptadienal, 1-octen-3-ol, octanal, (E)-2-octenal (E,E)-2,4-nonadienal and furan-2-pentyl. The content of two essential PUFAs, linoleic and α-linolenic acids, the known substrates of LOX in plants, was higher in TGP flours, indicating the efficacy of the CRISPR-mediated gene editing in minimizing their oxidation and the further modification of PUFAs and their products. The collection of VOCs from the headspace of ground pea seeds, using a portable eNose also distinguished the TGP and WT lines. Multiple regression analysis showed that LOX activity correlated with the two VOCs, heptanal and (E,E)-2,4-heptadienal in pea flours. Partial Least Squares Regression (PLS-R) plot for selected PUFAs, VOCs, and sensor responses in WT and TGP lines showed distinct clusters for WT and TGP lines. Together this data demonstrates the utility of CRISPR mediated mutagenesis of PsLOX2 to quickly improve aroma and fatty acid (FA) profiles of pea seeds of an elite Canadian variety.

What's Up Wednesday: Optimizing Educational Rounding to Improve Outcomes

The role of the nursing professional development practitioner is to identify gaps in practice and determine opportunities for learning. Scanning the environment is one of the crucial inputs of the nursing professional development practice model. However, owing to the complexities of today's patient care environment, engaging staff at the point of care presents formidable challenges. This article details how professional development specialists at a community hospital developed and implemented a program to both engage bedside staff and improve outcomes.

Gallium arsenide optical phased array photonic integrated circuit

A 16-channel optical phased array is fabricated on a gallium arsenide photonic integrated circuit platform with a low-complexity process. Tested with a 1064 nm external laser, the array demonstrates 0.92° beamwidth, 15.3° grating-lobe-free steering range, and 12 dB sidelobe level. Based on a reverse biased p-i-n structure, component phase modulators are 3 mm long with DC power consumption of less than 5 µW and greater than 770 MHz electro-optical bandwidth. Separately fabricated 4-mm-long phase modulators based on the same structure demonstrate single-sided Vπ·L modulation efficiency ranging from 0.5 V·cm to 1.22 V·cm when tested at wavelengths from 980 nm to 1360 nm.

Snapshot of proteomic changes in Aspergillus oryzae during various stages of fermentative processing of pea protein isolate

Pea (Pisum sativum) is one of the most abundant and sustainable alternate source of protein. Although pea proteins have good quantities of most of the essential amino acids, they have a limited supply of tryptophan, methionine and cysteine. Moreover, pea proteins have poor techno-functional properties compared to proteins from animal sources, limiting their use in certain food applications. Bioprocessing techniques like solid-state fermentation (SSF) and enzymatic processing have been explored to improve the nutrient profile and functionality of pea proteins. However, there is a lack of information about proteomic changes in the food matrix during fermentation of the pea substrate. In this research, samples during SSF of pea protein isolate with Aspergillus oryzae were used for shotgun mass spectrometry (LC-MS/MS) analysis to identify the underlying functional pathways which play direct or indirect roles in enabling the colonization of the substrate leading to potential improvement of functional and nutritional value of pea protein. Results revealed the identity of A. oryzae proteins involved in different metabolic pathways that differed during various stages of SSF. Among them, methionine synthase was identified as an abundant protein, which catalyzes methionine biosynthesis. This might suggest how fermentation processes could be used to improve the presence of sulfur containing amino acids to rebalance the essential amino acid profile and improve the nutritional quality of pea proteins.

Valorization of wastes and by-products of nuts, seeds, cereals and legumes processing

Wastes and by-products of nuts, seeds, cereals and legumes carry a unique potential for valorization into value-added ingredients due to their protein, dietary fiber, antioxidant, vitamin and mineral contents. The most crucial factor in the recovery of value-added ingredients and bioactives from the wastes and by-products is the utilization of the most efficient extraction technique. This work is an overview of the classification of wastes and by-products of nuts, seeds, cereals and legumes processing, the methods used in the extraction of valuable compounds such as proteins, dietary fibers, phenolics, flavonoids and other bioactives. This chapter provides insights on the promising applications of extracted ingredients in various end products. A special emphasis is given to the challenges and improvement methods for extraction of value-added compounds from wastes and by-products of nuts, seeds, cereals and legumes processing.

Plant leaf proteins for food applications: Opportunities and challenges

Plant-based proteins are gaining a lot of attention for their health benefits and are considered as an alternative to animal proteins for developing sustainable food systems. Against the backdrop, ensuring a healthy diet supplemented with good quality protein will be a massive responsibility of governments across the globe. Increasing the yield of food crops has its limitations, including low acceptance of genetically modified crops, land availability for cultivation, and the need for large quantities of agrochemicals. It necessitates the sensible use of existing resources and farm output to derive the proteins. On average, the protein content of plant leaves is similar to that of milk, which can be efficiently tapped for food applications across the globe. There has been limited research on utilizing plant leaf proteins for food product development over the years, which has not been fruitful. However, the current global food production scenario has pushed some leading economies to reconsider the scope of plant leaf proteins with dedicated efforts. It is evident from installing pilot-scale demonstration plants for protein extraction from agro-food residues to cater to the protein demand with product formulation. The present study thoroughly reviews the opportunities and challenges linked to the production of plant leaf proteins, including its nutritional aspects, extraction and purification strategies, anti-nutritional factors, functional and sensory properties in food product development, and finally, its impact on the environment. Practical Application: Plant leaf proteins are one of the sustainable and alternative source of proteins. It can be produced in most of the agroclimatic conditions without requiring much agricultural inputs. It's functional properties are unique and finds application in novel food product formulations.

Improvement of the nutritional quality of lentil flours by infrared heating of seeds varying in size

The present study aimed to tackle research gaps regarding how infrared heating affected macro- and micronutrients of lentil flours from seeds varying in size. Infrared treatments reduced resistant starch contents of lentil flours from 26.1-33.6% to 6.0-17.8%, increased protein digestibility from 73.6-75.0% to 78.2-82.2%, and enhanced soluble dietary fiber contents from 6.1-7.8% to 7.4-10.3%. Infrared treatments did not alter the primary limiting amino acid of Greenstar and Imvincible lentil flours (tryptophan) but changed that of Maxim to methionine + cysteine at 150 °C heating. Regarding micronutrients, the thermal modifications decreased the levels of heat-labile B vitamins, including B₁ (thiamine), B₃ (niacin), and B₉ (mainly 5-methylterahydrofolate), consistent with reducing α-amylase activity to an undetectable level in all the three lentil flours. The novel findings from this research will be meaningful for the agri-food industry to utilize infrared processing as an effective and clean-label approach to improving the nutritional profiles of lentil and other flours.

Structure - Functionality of lentil protein-polyphenol conjugates

Lentil protein isolate (LPI) was conjugated with plant polyphenols (quercetin, rutin, ellagic acid), and the structural and functional characteristics of the conjugates were determined in comparison with the proteins and pure polyphenols. The interaction between polyphenols and protein was achieved by a grafting method at pH 9.0 in the presence of atmospheric oxygen. Surface plasmon resonance measurements showed polyphenols' direct interaction with LPI, with the order of binding strength quercetin > ellagic acid > rutin. The degree of conjugation also followed the same order. Structural analysis of the conjugates was performed using FTIR, intrinsic fluorescence, and surface hydrophobicity. A significant improvement in DPPḢ radical scavenging and ferric reducing antioxidant power of the conjugates was observed compared to the polyphenols. However, there was a decrease in the surface activity of the conjugates compared to LPI. Such conjugation provides a novel way to combine the advantages of using plant protein and polyphenols in developing a novel food ingredient.

Heat induced gelation of pulse protein networks

This study examines the effect of salts (0.5 M NaCl or 0.25 M CaCl₂) and protein concentration (7.5-15%) on the gel-forming abilities of lentil (LPC), yellow pea (YPC), and faba bean (FPC) protein concentrates formed at pH 7.0. The surface hydrophobicity of YPC (84.8 arbitrary units, a.u.) was found to be lower than LPC (147.2 a.u.) and FPC (135.0 a.u.). In contrast, the surface charge for LPC, YPC, and FPC was -37.8, -28.4, and -29.3 mV, respectively. The Lg/Vn ratio of YPCs was determined as 0.65 followed by LPC (0.57) and FPC (0.41). The presence of salts reduced the least gelling concentration. LPC and FPC also appeared to have a more ordered structure than YPC as evident by CLSM. The network appeared more ordered as the protein concentration increased or in the presence of NaCl or CaCl₂ according to CLSM and synchrotron based micro computed tomography (µCT).

Impact of alcohol washing on the flavour profiles, functionality and protein quality of air classified pea protein enriched flour

In this study the potential of aqueous solvent washing on removing off-flavours in air classified pea protein-enriched flour (PPEF) was investigated. Unpleasant flavour compounds are one of the main deterrents to the application of pulses. PPEF was treated with ethanol or isopropanol at three different concentrations (20%, 50%, and 80%) to remove the volatiles related to unpleasant beany, earthy and astringent flavours. Headspace solid phase microextraction followed by GC-MS was used to identify the flavour compounds in untreated and treated PPEF. Besides the flavour profile, changes to their proximate composition, colour, functionality and protein quality were compared among untreated and treated samples. Higher concentrations of ethanol and isopropanol (50% and 80%) showed greater effectiveness in removing flavour compounds by reducing the total peak area by 82%-94%. Protein content in all treated samples (58.2%-64.3% d.b.) increased compared to untreated PPEF (55.5%) as a result of purification due to the decrease in ash, lipid and carbohydrate content. However, alcohol treatment reduced the protein solubility and oil holding capacity in all samples by 38.3%-75.9%, and 16.7%-30.2%, respectively. Although in vitro protein digestibility was improved with the solvent treatments, the amino acid scores of those samples became lower (i.e., reduced levels of methionine, cysteine or tryptophan) resulting in up to a 27.8% reduction in in vitro protein digestibility correct amino acid scores. Both ethanol and isopropanol at 50% and 80% concentration proved to be effective in removing flavour compounds in PPEF with some modifications on the chemical compositions, protein functionalities and quality.

Changes in levels of phytic acid, lectins and oxalates during soaking and cooking of Canadian pulses

Raw and processed (soaked or cooked) seeds of peas, lentils, chickpeas, fava beans and common beans were studied for their contents of antinutritional factors (lectins, phytic acid, total and soluble oxalates), along with soybean as a control. Analysis of variance indicated that legume type, treatment and their interactive effects were significant on these antinutrients. The raw soybean seed was found to contain the highest levels of lectins (692.8 HU/mg), phytic acid (22.91 mg/g), total oxalate (370.5 mg/100 g) and soluble oxalate (200.7 mg/100 g) among all investigated seeds. Relatively high contents of lectins were detected in beans (87.69-88.59 HU/mg) and other pulses ranging from 2.73-11.07 HU/mg. Phytic acid in Canadian pulses varied slightly from 8.55-22.85 mg/g. Total oxalates were variable, ranging from 244.7-294.0 mg/100 g in peas, 168.6-289.1 mg/100 g in lentils, 241.5-291.4 mg/100 g in fava beans, 92.2-214.0 mg/100 g in chickpeas and 98.86-117.0 mg/100 g in common beans. Approximately 24-72% of total oxalate appeared to be soluble in all investigated pulses. Soaking the seeds in distilled water significantly decreased the contents of lectins (0.11-5.18%), total oxalate (17.40-51.89%) and soluble oxalate (26.66-56.29%), but had no impact on phytic acid. The cooking process was found to be more effective in reducing levels of all the investigated antinutritional factors, except phytic acid in common beans and soybean.

An Embryonic and Induced Pluripotent Stem Cell Model for Ovarian Granulosa Cell Development and Steroidogenesis

Embryoid bodies (EBs) can serve as a system for evaluating pluripotency, cellular differentiation, and tissue morphogenesis. In this study, we use EBs derived from mouse embryonic stem cells (mESCs) and human amniocyte-derived induced pluripotent stem cells (hAdiPSCs) as a model for ovarian granulosa cell (GC) development and steroidogenic cell commitment. We demonstrated that spontaneously differentiated murine EBs (mEBs) and human EBs (hEBs) displayed ovarian GC markers, such as aromatase (CYP19A1), FOXL2, AMHR2, FSHR, and GJA1. Comparative microarray analysis identified both shared and unique gene expression between mEBs and the maturing mouse ovary. Gene sets related to gonadogenesis, lipid metabolism, and ovarian development were significantly overrepresented in EBs. Of the 29 genes, 15 that were differentially regulated in steroidogenic mEBs displayed temporal expression changes between embryonic, postnatal, and mature ovarian tissues by polymerase chain reaction. Importantly, both mEBs and hEBs were capable of gonadotropin-responsive estradiol (E2) synthesis in vitro (217-759 pg/mL). Live fluorescence-activated cell sorting-sorted AMHR2⁺ granulosa-like cells from mEBs continued to produce E2 after purification (15.3 pg/mL) and secreted significantly more E2 than AMHR2^- cells (8.6 pg/mL, P < .05). We conclude that spontaneously differentiated EBs of both mESC and hAdiPSC origin can serve as a biologically relevant model for ovarian GC differentiation and steroidogenic cell commitment. These cells should be further investigated for therapeutic uses, such as stem cell-based hormone replacement therapy and in vitro maturation of oocytes.

Abstract 4384: Targeted sequencing reveals distinct and rare pathogenic variants in Caucasians with colorectal cancer

PURPOSE: Next-generation sequencing (NGS) is currently used to establish mutational profiles in many multigene diseases such as colorectal cancer (CRC) which is on the rise in many parts of the developing World including in the Middle East. Little is known about its genetic hallmarks in these populations. AIM: To identify variants in 15 CRC-associated genes in patients of Iranian descent.

METHODS: CRC specimens from 63 patients were used to establish the variants’ profile on an Ion Torrent platform by targeted exome sequencing. To rule out technical artifacts, the variants were validated in 13 of these samples using an Illumina NGS platform. Validated variants were annotated and compared to variants from publically available databases. An in-silico functional analysis was performed. MSI status of the analyzed samples was established. RESULTS: There were 51 validated variants distributed on 12 genes: 22% MSH3 (n=11/51), 10% MSH6 (n=5/51), 8% AMER1 (n=4/51), 20% APC (n=10/51), 2% BRAF (n=1/51), 2% KRAS (n=1/51), 12% PIK3CA (n=6/51), 8% TGFβR2A (n=4/51), 2% SMAD4 (n=1/51), 4% SOX9 (n=2/51), 6% TCF7L2 (n=3/51), and 6% TP53 (n=3/51). Most known and distinct variants were in mismatch repair genes (MMR, 32%) and APC (20%). Among oncogenes, PIK3CA was the top target (12%). MSH3 variants were more frequent and predominantly homozygous in the analyzed population.

CONCLUSION: These results illustrate for the first time CRC mutational profile in Iranian patients. MSH3, MSH6, APC and PIK3CA genes seem to play a bigger role in the path to cancer in this population. This is especially true for MSH3 variants that were very frequent and predominantly homozygous as these will associate with the EMAST phenotype that has prognostic implications. These findings will potentially lead to informed genetic diagnosis protocol and targeted therapeutic strategies.

Citation Format: Pooneh Mokarram, Sudhir Varma, Hamed Azimi, Hasti Olumi, Ali reza Safarpour, Michael Nickerson, Hassan Brim, Hassan Ashktorab. Targeted sequencing reveals distinct and rare pathogenic variants in Caucasians with colorectal cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 4384. doi:10.1158/1538-7445.AM2017-4384

Influence of the extrusion parameters on the physical properties of chickpea and barley extrudates

In this research, the effects of extrusion processing [exit-die temperature (120-150°C), moisture content (20-24% wet basis), and screw speed (260-340 rpm)] on the specific mechanical energy and physical properties (expansion ratio, bulk density, and hardness) of desi chickpea and hullless barley extrudates were estimated using response surface methodology. Exit-die temperature and feed moisture content, as well as the interaction between them were the factors that affected the product responses the most. Significant correlation was found between the hardness and bulk density (positive), hardness and expansion ratio (negative), and bulk density and expansion ratio (negative) for both chickpea and barley extrudates. Desirable characteristics (high expansion, low bulk density, and hardness) for chickpea were obtained at high exit-die temperature, relatively high moisture, and high screw speed. As for the barley extrudates, high exit-die temperature, low moisture, and moderate to high screw speed were identified as optimal.

A phase II study of axitinib in advanced neuroendocrine tumors

Neuroendocrine tumors (NETs) are highly vascular neoplasms overexpressing vascular endothelial growth factor (VEGF) as well as VEGF receptors (VEGFR). Axitinib is a potent, selective inhibitor of VEGFR-1, -2 and -3, currently approved for the treatment of advanced renal cell carcinoma. We performed an open-label, two-stage design, phase II trial of axitinib 5mg twice daily in patients with progressive unresectable/metastatic low-to-intermediate grade carcinoid tumors. The primary end points were progression-free survival (PFS) and 12-month PFS rate. The secondary end points included time to treatment failure (TTF), overall survival (OS), overall radiographic response rate (ORR), biochemical response rate and safety. A total of 30 patients were enrolled and assessable for toxicity; 22 patients were assessable for response. After a median follow-up of 29months, we observed a median PFS of 26.7months (95% CI, 11.4-35.1), with a 12-month PFS rate of 74.5% (±10.2). The median OS was 45.3 months (95% CI, 24.4-45.3), and the median TTF was 9.6months (95% CI, 5.5-12). The best radiographic response was partial response (PR) in 1/30 (3%) and stable disease (SD) in 21/30 patients (70%); 8/30 patients (27%) were unevaluable due to early withdrawal due to toxicity. Hypertension was the most common toxicity that developed in 27 patients (90%). Grade 3/4 hypertension was recorded in 19 patients (63%), leading to treatment discontinuation in six patients (20%). Although axitinib appears to have an inhibitory effect on tumor growth in patients with advanced, progressive carcinoid tumors, the high rate of grade 3/4 hypertension may represent a potential impediment to its use in unselected patients.

Abstract A1-31: Molecular characteristics and predictors of poor prognosis in sporadic clear cell renal cancer among central/eastern European and United States patients

We investigated patient/tumor characteristics/inherited variants, hypoxia inducible factor 1 and 2 alpha (HIF1A/HIF2A) protein expression, and patient survival among Central European (CE) and United States (US) clear cell renal cancer (ccRCC) patients from two case-control studies. VHL inactivation, HIF1A, and HIF2A expression have been implicated in RCC and angiogenesis. GWAS studies have identified EPAS1 variants encoding the protein HIF2A associated with RCC risk. We conducted a hospital-based case-control study in Central/Eastern Europe (CE) and a population-based study in the US (Detroit, Chicago) that included whites and blacks. We used data on: i) patient/tumor characteristics, ii) inherited tagging single nucleotide polymorphisms (SNPs) in genes involved in the VHL-HIF pathway (HIF1A, EPAS1, VHL), HIF1A and HIF2A protein expression using immunohistochemical (IHC) methods, and survival from 696 CEERCC and 328 US ccRCC cases. ccRCC patients from CE Europe were older, presented at a higher grade, stage, with larger tumors, had lower BMI, less family history and smoked less (all p&lt;0.0001) compared to US cases. US cases demonstrated higher intensity HIF1A and HIF2A protein expression compared to CE cases (p&lt;0.0001). Black US ccRCC cases were more likely to be hypertensive (p&lt;0.0001) and have lower HIF2A protein expression compared to white US cases. HIF1A and HIF2A were examined for associations with patient/tumor characteristics. In the US study, younger patients had higher levels of HIF2A expression compared to older cases and high BMI was associated with HIF1A expression. In both studies, tumor grade, stage and size at diagnosis were associated with lower HIF1A and HIF2A expression. In analyses adjusted for center, race, sex, age, hypertension, BMI, smoking, tumor grade and stage, HIF1A expression was significantly associated with HIF2A expression (P-trend&lt;0.0001). We assessed associations of variants in EPAS1 (N=16), HIF1A (N=11), and VHL (N=9) with HIF1A and HIF2A expression in ccRCC tissue using tissue microarrays. Seven HIF1A SNPs were significantly associated with HIF1A expression and one EPAS1 SNP (rs1374748) with HIF2A expression. Median survival time was longer in CE compared to USRCC cases (100.3 vs. 86.0 months, p=0.001), women than men (97.1 vs 91.0 months, p=0.02) but similar among whites and blacks in the US study (86.0 vs 87.0 months). In Cox proportional hazard models, in both studies combined, risk of death was higher for those with large tumors (&gt;4cm, p&lt;0.0001) and with a higher stage 1 vs 2, 3+4 (p&lt;0.0001, both) In contrast, ccRCC-specific survival was higher among USRCC than CE patients (19.8 vs 38.0 months, p=0.04) but similar among white compared to black US ccRCC patients (37.0 vs 40.0 months, p=0.50).

Citation Format: Lee Moore, Petra Lenz, Meredith Yeager, Ruth Pfeiffer, Ghislaine Scelo, Mark Purdue, David Zaridze, Kendra Schwartz, Neonilia szeszenia-Dabrowska, Faith Davis, Joanne Colt, vladimir Janout, Marie Navritalova, Paolo Boffetta, Laurie Burdette, Sara Karami, Paul Brennan, Jon Hofmann, Michael Nickerson, Wong-Ho Chow, Margaret Tucker, Stephen Chanock, Stephen Hewitt, Jorge Toro, Nat Rothman. Molecular characteristics and predictors of poor prognosis in sporadic clear cell renal cancer among central/eastern European and United States patients. [abstract]. In: Proceedings of the AACR Special Conference on Translation of the Cancer Genome; Feb 7-9, 2015; San Francisco, CA. Philadelphia (PA): AACR; Cancer Res 2015;75(22 Suppl 1):Abstract nr A1-31.

Abstract 3930: Targeted cancer gene sequencing identifies potential causative novel candidate mutations among Caucasian colon carcinogenesis

Much of the sporadic colorectal cancer's (CRC) underlying genetic ‘cancer driver’ mutations are unknown in patients from specific ethnic groups. Here, we report the identification of distinct novel variants from adenoma and CRC patients in mismatch repair (MMR) genes MHS3 and MSH6, and in PIK3CA and APC.

We developed a panel of 20 frequently altered colon cancer genes comprised of ACVR2A, APC, ARID1A, BRAF, FAM123B, FBXW7, KRAS, MSH2, MSH3, MSH6, NRAS, PIK3CA, POLE, PTEN, SMAD2, SMAD4, SOX9, TCF7L2, TGFBR2, and TP53 for targeted sequencing in 65 colon tissues, comprised of 1 normal tissue sample, 2 adenomas, and 63 tumors. Multiplex PCR and Ion Torrent sequencing was used to examine 98.8% of the targeted exons and splice junctions at a depth of sequencing that allowed for high confidence variant calling (most bases were covered by ≥ 500 reads). After alignment and variant calling, we annotated the variants with information from the 1000 Genomes Project, COSMIC, Polyphen2, and PFAM domain and transcription factor motifs. Excluding synonymous SNVs, 3 variants in adenoma, and 692 variants in tumors were detected. Two were known pathogenic variants (MSH6 p.R965H and APC p.R1432X). Novel variants (286, 244, and 115) were found in MMR genes (MSH6 and MSH3), APC, and PIK3CA, respectively. Most of the MMR (n = 98), APC (n = 128), and PIK3CA (n = 43) variants are deleterious. Notably, among the 63 CRC cases, [(29/61 = 46%) 46%) for MSH3, MSH6] [(19/63 = 30%) (30%) for PIK3CA] [31/63 = 49%) (49%) for APC)] carried likely deleterious MMR, PIK3CA and APC mutations, respectively, suggesting the value of a broad cancer gene panel. These finding further highlight the relevance of APC, PIK3CA genes in CRC onset but also the potential underestimation of the MSI-H in sporadic CRC as many of the novel mutations in MMR gens detected here were of a deleterious nature.

Citation Format: Hassan Ashktorab, Michael Nickerson, Sudhir Varma, Pooneh Mokarram, fakhraddin Naghibalhossaini, Lee Moore, Joseph Boland, Sara Bass, Meredith Yeager, Wen-Yi Haung, Hassan Brim. Targeted cancer gene sequencing identifies potential causative novel candidate mutations among Caucasian colon carcinogenesis. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 3930. doi:10.1158/1538-7445.AM2015-3930

Pax6- and Six3-mediated induction of lens cell fate in mouse and human ES cells

Embryonic stem (ES) cells provide a potentially useful in vitro model for the study of in vivo tissue differentiation. We used mouse and human ES cells to investigate whether the lens regulatory genes Pax6 and Six3 could induce lens cell fate in vitro. To help assess the onset of lens differentiation, we derived a new mES cell line (Pax6-GFP mES) that expresses a GFP reporter under the control of the Pax6 P0 promoter and lens ectoderm enhancer. Pax6 or Six3 expression vectors were introduced into mES or hES cells by transfection or lentiviral infection and the differentiating ES cells analyzed for lens marker expression. Transfection of mES cells with Pax6 or Six3 but not with other genes induced the expression of lens cell markers and up-regulated GFP reporter expression in Pax6-GFP mES cells by 3 days post-transfection. By 7 days post-transfection, mES cell cultures exhibited a>10-fold increase over controls in the number of colonies expressing γA-crystallin, a lens fiber cell differentiation marker. RT-PCR and immunostaining revealed induction of additional lens epithelial or fiber cell differentiation markers including Foxe3, Prox1, α- and β-crystallins, and Tdrd7. Moreover, γA-crystallin- or Prox1-expressing lentoid bodies formed by 30 days in culture. In hES cells, Pax6 or Six3 lentiviral vectors also induced lens marker expression. mES cells that express lens markers reside close to but are distinct from the Pax6 or Six3 transduced cells, suggesting that the latter induce nearby undifferentiated ES cells to adopt a lens fate by non-cell autonomous mechanisms. In sum, we describe a novel mES cell GFP reporter line that is useful for monitoring induction of lens fate, and demonstrate that Pax6 or Six3 is sufficient to induce ES cells to adopt a lens fate, potentially via non-cell autonomous mechanisms. These findings should facilitate investigations of lens development.

Encapsulation of flaxseed oil using a benchtop spray dryer for legume protein-maltodextrin microcapsule preparation

Flaxseed oil was microencapsulated employing a wall material matrix of either chickpea (CPI) or lentil protein isolate (LPI) and maltodextrin using a benchtop spray dryer. Effects of emulsion formulation (oil, protein and maltodextrin levels) and protein source (CPI vs LPI) on the physicochemical characteristics, oxidative stability, and release properties of the resulting capsules were investigated. Microcapsule formulations containing higher oil levels (20% oil, 20% protein, 60% maltodextrin) were found to have higher surface oil and lower encapsulation efficiencies. Overall, LPI-maltodextrin capsules gave higher flaxseed oil encapsulation efficiencies (∼88.0%) relative to CPI-maltodextrin matrices (∼86.3%). However, both designs were found to provide encapsulated flaxseed oil protection against oxidation over a 25 d room temperature storage study relative to free oil. Overall, ∼37.6% of encapsulated flaxseed oil was released after 2 h under simulated gastric fluid, followed by the release of an additional ∼46.6% over a 3 h period under simulated intestinal fluid conditions.

Sexual dimorphism of the intracellular heat shock protein 72 response

The majority of previous work examining stress responses has been done in males. Recently, it has become clear that the impact of stressor exposure is modulated by sex. One stress response that may be affected by sex is the induction of intracellular heat shock protein (HSP) 72, which is a stress- responsive molecular chaperone that refolds denatured proteins and promotes cellular survival. The following study compared HSP72 in males and females and also examined whether the estrous cycle altered HSP72 induction in females. We hypothesized that females compared with males would have a constrained HSP72 response after an acute stressor and that the stress-induced HSP72 response in females would fluctuate with the estrous cycle. Male and female F344 rats were either left in their home cage or exposed to acute tail-shock stress (8–10/group). Immediately following stressor, trunk blood was collected and tissues were flash frozen. Vaginal smear and estrogen enzyme immunoassay were used to categorize the phase of estrous. Results show that female rats had a greater corticosterone response than males, that both males and females exhibit a stress-induced release of progesterone, and that males and females had equal levels of stress-induced circulating norepinephrine. Sexual dimorphism of the HSP72 (ELISA) response existed in pituitary gland, mesenteric lymph nodes, and liver such that female rats had an attenuated HSP72 response compared with males after stress. The adrenal glands, spleen, and heart did not exhibit sexual dimorphism of the HSP72 response. The estrous cycle did not have a significant effect on basal or stress-induced HSP72 in females.

Catecholamines mediate stress-induced increases in peripheral and central inflammatory cytokines

Proinflammatory cytokines act at receptors in the CNS to alter physiological and behavioral responses. Exposure to stressors increases both peripheral and central proinflammatory cytokines, yet the mechanism(s) of induction remain unknown. Experiments here examined the role of catecholamines in the in vivo induction of proinflammatory cytokines following tailshock stress. Rats were pretreated i.p. with 2.0 mg/kg prazosin (alpha1-adrenoceptor antagonist), 10.0 mg/kg propranolol (beta-adrenoceptor antagonist), or 5.0 mg/kg labetalol (alpha1- and beta-adrenoceptor antagonist) 30 min prior to tailshock exposure and plasma interleukin-1beta (IL-1beta) and IL-6, along with tissue interleukin-1beta from the hypothalamus, hippocampus, and pituitary were measured immediately following stressor termination. Prazosin attenuated stress-induced plasma IL-1beta and IL-6, but had no effect on tissue IL-1beta levels, while propranolol attenuated plasma IL-6 and blocked tissue IL-1beta elevation, and labetalol, which cannot cross the blood-brain barrier, attenuated plasma IL-1beta and IL-6, blocked pituitary IL-1beta, but had no effect on central tissue IL-1beta levels. Furthermore, administration of 50.0 mg/kg N-(2-chloroethyl)-N-ethyl-2-bromobenzylamine hydrochloride, a neurotoxin that lesions neural projections from the locus coeruleus, prevented stress-induced elevation in hippocampal IL-1beta, a region highly innervated by the locus coeruleus, but had no effect on hypothalamic IL-1beta, a region that receives few locus coeruleus projections. Finally, i.p. injection of 5.0 mg/kg isoproterenol (beta-adrenoceptor agonist) was sufficient to induce circulating IL-1 and IL-6, and tissue IL-1beta. These data suggest catecholamines play an important role in the induction of stress-induced proinflammatory cytokines and that beta-adrenoceptors are critical for tissue IL-1beta induction, while both alpha- and beta-adrenoceptors contribute to the induction of plasma cytokines.

Physical activity alters the brain Hsp72 and IL-1beta responses to peripheral E. coli challenge

Physically active rats have facilitated heat shock protein 72 (Hsp72) responses after stressor exposure in both brain and peripheral tissues compared with sedentary rats. This study verifies that physically active animals do not have elevated Hsp72 levels compared with sedentary animals in the hypothalamus, pituitary, or dorsal vagal complex. We then examined whether 1) physically active rats respond more efficiently than sedentary rats to a bacterial challenge; 2) peripheral immune challenge elicits brain induction of Hsp72; 3) this induction is facilitated by prior freewheel running; and 4) Hsp72 upregulation produced by peripheral immune challenge results in a commensurate decrease in the proinflammatory cytokine IL-1beta. Adult male Fischer 344 rats were housed with either a mobile or locked running wheel. Six weeks later, rats were injected intraperitoneally with saline or Escherichia coli and killed 30 min, 2.5 h, 6 h, and 24 h later. Serum endotoxin and IL-1beta, and peritoneal fluid endotoxin and E. coli colony-forming units (CFUs) were measured. Hsp72 and IL-1beta were measured in hypothalamus, pituitary, and dorsal vagal complex. The results were that physically active rats had a faster reduction in endotoxin and E. coli CFUs and lower levels of circulating endotoxin and cytokines compared with sedentary rats. E. coli challenge elicited significantly greater time-dependent increases of both Hsp72 and IL-1beta in hypothalamus, pituitary, and dorsal vagal complex of physically active animals but not sedentary animals. Contrary to our hypothesis, increases in Hsp72 were positively correlated with IL-1beta. This study extends our findings that physical activity facilitates stress-induced Hsp72 to include immunological stressors such as bacterial challenge and suggests that brain Hsp72 and IL-1beta responses to peripheral immune challenge may contribute to exercise-mediated resistance to long-term sickness.

Splenic norepinephrine depletion following acute stress suppresses in vivo antibody response

Exposure to an intense acute stressor immediately following immunization leads to a reduction in anti-KLH IgM, IgG, and IgG2a, but not IgG1. Stress also depletes splenic norepinephrine (NE) content. Immunization during pharmacological (alpha-methyl-p-tyrosine) or stress-induced splenic NE depletion results in antibody suppression similar to that found in rats immunized prior to stressor exposure. Prevention of splenic NE depletion during stress by tyrosine, but not pharmacological elevation (mirtazapine) of NE, resulted in normal antibody responses. These data support the hypothesis that splenic NE depletion is necessary and sufficient for stress-induced suppression of antibody to a T-cell dependent antigen.

Deletions in an endopolygalacturonase gene cluster correlate with non-melting flesh texture in peach

Endopolygalacturonase activity during softening of peach [Prunus persica (L.) Batsch] fruit is thought to be responsible for the melting flesh texture. A cDNA, PRF5, was previously identified as a fruit-related endopolygalacturonase that may be involved with the texture differences (Lester et al. 1996). We found that all eight of the non-melting flesh cultivars in this study had a deletion in at least one of their PRF5-related polygalacturonase genes, while none of the melting flesh cultivars did. There were three sources of the non-melting trait, as identified by the extent of the deletions. One source of non-melting flesh resulted in a complete deletion of PRF5-related genes while the other two sources had deletions of a subset of those genes, suggesting a cluster of polygalacturonase genes at the melting flesh locus. All of the non-melting flesh cultivars used for this study had greatly reduced or undetectable mRNA levels of PRF5-related polygalacturonase during fruit softening. Using PCR techniques, it was determined that either the PRF5 gene, or more likely, an unidentified peach polygalacturonase at the same locus, is responsible for melting flesh texture determination.

Disruption of a novel MFS transporter gene, DIRC2, by a familial renal cell carcinoma-associated t(2;3)(q35;q21)

Previously, we described a family with a significantly increased predisposition for renal cell cancer co-segregating with a t(2;3)(q35;q21) chromosomal translocation. Several primary tumors of the clear cell type from different family members were analyzed at a molecular level. Loss of the derivative chromosome 3 was consistently found. In addition, different somatic Von Hippel Lindau (VHL) gene mutations were observed in most of the tumors analyzed, even within the same patient. Based on these results a multistep tumorigenesis model was proposed in which (non-disjunctional) loss of the derivative chromosome 3 represents an early event and somatic mutation of the VHL gene represents a late event related to tumor progression. More recently, however, we noted that these two anomalies were absent in at least one early-stage tumor sample that we tested. Similar results were obtained in another family with renal cell cancer and t(3;6)(q12;q15), thus suggesting that another genetic event may precede these two oncogenetic steps. We speculate that deregulation of a gene(s) located at or near the translocation breakpoint may act as such. In order to identify such genes, a detailed physical map encompassing the 3q21 breakpoint region was constructed. Through a subsequent positional cloning effort we found that this breakpoint targets a hitherto unidentified gene, designated DIRC2 (disrupted in renal cancer 2). Computer predictions of the putative DIRC2 protein showed significant homology to different members of the major facilitator superfamily (MFS) of transporters. Based on additional DIRC2 expression and mutation analyses, we propose that the observed gene disruption may result in haplo-insufficiency and, through this mechanism, in the onset of tumor growth.

Denervation and beta-adrenoreceptors of the cat nictitating membrane

1. Dose-response curves to the relaxant effects of isoprenaline, salbutamol, adrenaline and noradrenaline were determined on the partially contracted smooth muscles of the cat nictitating membrane following alpha-adrenoreceptor blockade in order to test the hypothesis of a causal relationship between the inhibition of neuronal uptake and denervation supersensitivity. 2. Denervation did not produce supersensitivity of the nictitating membrane to the beta-adrenoreceptor-mediated relaxant effects of any of the four agents studied. 3. The sensitivity of the inferior muscle was greater than that of the medial muscle to agents which were good substrates for neuronal uptake (adrenaline and noradrenaline) as well as to those which were not (isoprenaline and salbutamol). 4. Denervation did not alter the antagonist activity of beta-adrenoreceptor blockers propranolol (nonselective) and metoprolol (beta 1-blocker) against isoprenaline or of H 35/25 (beta 2-blocker) against salbutamol. 5. These results do not support the hypothesis of a casual relationship between inhibition of neuronal uptake and supersensitivity to sympathomimetic amines.

Beta-adrenoreceptors of the cat nictitating membrane

1. The relaxant effects of isoprenaline, salbutamol, adrenaline and noradrenaline on the partially contracted isolated nictitating membrane of the cat were determined in the absence and the presence of alpha-adrenoreceptor blockade. 2. It was possible to demonstrate significant relaxant effects of isoprenaline and salbutamol in the absence as well as in the presence of alpha-adrenoreceptor blockade. However, the relaxant effects of adrenaline and noradrenaline could not be demonstrated in the absence of alpha-adrenoreceptor blockade. 3. Molar concentrations (EC30) of isoprenaline, salbutamol and adrenaline causing 30% relaxation of the tone did not significantly differ from each other; EC30 of each of these agents was significantly less than that of noradrenaline. 4. Beta 1-Adrenoreceptor antagonist metoprolol was less potent than beta 2-antagonist H 35/25 in antagonizing the effect of salbutamol; metoprolol was more potent than H 25/35 in antagonizing noradrenaline. Both these agents were effective antagonists of isoprenaline; however, metoprolol and H 25/35 in combination produced greater antagonism of isoprenaline than did each antagonist separately. 5. It is concluded that the cat nictitating membrane possesses both beta 1- and beta 2-adrenoreceptors which are responsible for the relaxant effects of sympathomimetic agents. A study of these receptors is, however, complicated by concomitant stimulation of alpha-adrenoreceptors.

Effects of sympathetic innervation and temperature on the properties of rat heart adrenoceptors

1. The pharmacological characteristics of adrenoceptors at different temperatures were assessed on the basis of the effects of various alpha- and beta-adrenoceptor agonists and antagonists on electrically-driven left atria and spontaneously-beating pairs of atria from rats. 2. Phenoxybenzamine (Pbz) potentiated inotropic responses of left atria to noradrenaline (NA) at 31 degrees C, produced significantly less potentiation at 24 degrees C and inhibited responses at 17 degrees C; it had little effect on responses to CaCl2. Both Pbz and phentolamine inhibited responses to phenylephrine more effectively at 17 than at 31 degrees C. N-cyclohexylmethyl-N-ethyl-beta-chloroethylamine hydrochloride (GD-131), a haloalkylamine with negligible alpha-adrenoceptor blocking activity, caused only potentiation of responses to NA at 17 degrees C. 3. The presence of phentolamine during incubation with Pbz eliminated block of responses to NA and revealed a potentiation that was equivalent at all three temperatures tested. Phentolamine did not alter the block of responses to 5-hydroxytryptamine by Pbz. Protection of alpha-adrenoceptors by phentolamine during exposure to [3H]-Pbz significantly decreased the amount of label bound to the myocardium at 17 degrees C, but did not alter binding at 31 degrees C. 4. Inhibition of responses to NA by propranolol decreased with temperature, and the magnitude of the change increased with the concentration of propranolol. Compared to 31 degrees C, the effect of the highest concentration of propranolol. (4.0 micronM) was significantly decreased at 24 degrees C, and the effects of all except the lowest concentration (0.04 micronM) were significantly decreased at 17 degrees C. 5. The potency of isoprenaline decreased and that of phenylephrine increased at low temperatures, and their potency ratio was much lower at 17 than at 31 degrees C for both the inotropic and chronotropic responses of spontaneously-beating atria. However, the ratio was unaffected by temperature in electrically-driven left atria. A similar difference between spontaneously-beating and driven preparations is apparent in the data of other workers, but its basis is not clear. 6. Atria from rats pretreated with 6-hydroxydopamine (6-OHDA) were sensitized to the effects of NA, and there was no increase in alpha-adrenoceptor properties at low temperatures. Little alpha-adrenoceptor activity could be demonstrated in chemically denervated atria at any temperature, 6-OHDA pretreatment did not alter the binding of [3H]-Pbz at 31 degrees C, but decreased it significantly at 17 degrees C. Pretreatment with reserpine caused some sensitization, but not significantly after the characteristics of the adrenoceptors or their responses to temperature. 7. It is concluded that the adrenoceptors of atria are affected by temperature in much the same way as those of frog hearts, although the transition from beta- to alpha-adrenoceptor properties may begin at a slightly higher temperature...