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991.
For half a century population genetics studies have put type II restriction endonucleases to work. Now, coupled with massively‐parallel, short‐read sequencing, the family of RAD protocols that wields these enzymes has generated vast genetic knowledge from the natural world. Here, we describe the first software natively capable of using paired‐end sequencing to derive short contigs from de novo RAD data. Stacks version 2 employs a de Bruijn graph assembler to build and connect contigs from forward and reverse reads for each de novo RAD locus, which it then uses as a reference for read alignments. The new architecture allows all the individuals in a metapopulation to be considered at the same time as each RAD locus is processed. This enables a Bayesian genotype caller to provide precise SNPs, and a robust algorithm to phase those SNPs into long haplotypes, generating RAD loci that are 400–800 bp in length. To prove its recall and precision, we tested the software with simulated data and compared reference‐aligned and de novo analyses of three empirical data sets. Our study shows that the latest version of Stacks is highly accurate and outperforms other software in assembling and genotyping paired‐end de novo data sets. 相似文献
992.
993.
Charles M. Strom Steven Rivera Christopher Elzinga Taraneh Angeloni Sun Hee Rosenthal Dana Goos-Root Martin Siaw Jamie Platt Cory Braastadt Linda Cheng David Ross Weimin Sun 《PloS one》2015,10(8)
The objective of this study was to design and validate a next-generation sequencing assay (NGS) to detect BRCA1 and BRCA2 mutations. We developed an assay using random shearing of genomic DNA followed by RNA bait tile hybridization and NGS sequencing on both the Illumina MiSeq and Ion Personal Gene Machine (PGM). We determined that the MiSeq Reporter software supplied with the instrument could not detect deletions greater than 9 base pairs. Therefore, we developed an alternative alignment and variant calling software, Quest Sequencing Analysis Pipeline (QSAP), that was capable of detecting large deletions and insertions. In validation studies, we used DNA from 27 stem cell lines, all with known deleterious BRCA1 or BRCA2 mutations, and DNA from 67 consented control individuals who had a total of 352 benign variants. Both the MiSeq/QSAP combination and PGM/Torrent Suite combination had 100% sensitivity for the 379 known variants in the validation series. However, the PGM/Torrent Suite combination had a lower intra- and inter-assay precision of 96.2% and 96.7%, respectively when compared to the MiSeq/QSAP combination of 100% and 99.4%, respectively. All PGM/Torrent Suite inconsistencies were false-positive variant assignments. We began commercial testing using both platforms and in the first 521 clinical samples MiSeq/QSAP had 100% sensitivity for BRCA1/2 variants, including a 64-bp deletion and a 10-bp insertion not identified by PGM/Torrent Suite, which also suffered from a high false-positive rate. Neither the MiSeq nor PGM platform with their supplied alignment and variant calling software are appropriate for a clinical laboratory BRCA sequencing test. We have developed an NGS BRCA1/2 sequencing assay, MiSeq/QSAP, with 100% analytic sensitivity and specificity in the validation set consisting of 379 variants. The MiSeq/QSAP combination has sufficient performance for use in a clinical laboratory. 相似文献
994.
995.
Usha Ramakrishnan Amanda Stinger Ann M. DiGirolamo Reynaldo Martorell Lynnette M. Neufeld Juan A. Rivera Lourdes Schnaas Aryeh D. Stein Meng Wang 《PloS one》2015,10(8)
Objective
We evaluated the effects of prenatal docosahexaenoic acid (DHA) supplementation on offspring development at 18 months of age.Design
Randomized placebo double-blind controlled trial.Settings
Cuernavaca, Mexico.Participants and Methods
We followed up offspring (n = 730; 75% of the birth cohort) of women in Mexico who participated in a trial of DHA supplementation during the latter half of pregnancy. We assessed the effect of the intervention on child development and the potential modifying effects of gravidity, gender, SES, and quality of the home environment.Interventions or Main Exposures
400 mg/day of algal DHA.Outcome Measures
Child development at 18 months of age measured using the Spanish version of the Bayley Scales of Infant Development-II. We calculated standardized psychomotor and mental development indices, and behavior rating scale scores.Results
Intent-to-treat differences (DHA-control) were: Psychomotor Developmental Index -0.90 (95% CI: -2.35, 0.56), Mental Developmental Index -0.26 (95% CI: -1.63, 1.10) and Behavior Rating Scale -0.01 (95% CI: -0.95, 0.94). Prenatal DHA intake attenuated the positive association between home environment and psychomotor development index observed in the control group (p for interaction = 0.03) suggesting potential benefits for children living in home environments characterized by reduced caregiver interactions and opportunities for early childhood stimulation.Conclusions
Prenatal DHA supplementation in a population with low intakes of DHA had no effects on offspring development at 18 months of age although there may be some benefit for infants from poor quality home environments.Trial Registration
Clinicaltrials.gov NCT00646360 相似文献996.
Tiejun Zhang Long-Xi Yu Ping Zheng Yajun Li Martha Rivera Dorrie Main Stephanie L. Greene 《PloS one》2015,10(9)
Drought resistance is an important breeding target for enhancing alfalfa productivity in arid and semi-arid regions. Identification of genes involved in drought tolerance will facilitate breeding for improving drought resistance and water use efficiency in alfalfa. Our objective was to use a diversity panel of alfalfa accessions comprised of 198 cultivars and landraces to identify genes involved in drought tolerance. The panel was selected from the USDA-ARS National Plant Germplasm System alfalfa collection and genotyped using genotyping by sequencing. A greenhouse procedure was used for phenotyping two important traits associated with drought tolerance: drought resistance index (DRI) and relative leaf water content (RWC). Marker-trait association identified nineteen and fifteen loci associated with DRI and RWC, respectively. Alignments of target sequences flanking to the resistance loci against the reference genome of M. truncatula revealed multiple chromosomal locations. Markers associated with DRI are located on all chromosomes while markers associated with RWC are located on chromosomes 1, 2, 3, 4, 5, 6 and 7. Co-localizations of significant markers between DRI and RWC were found on chromosomes 3, 5 and 7. Most loci associated with DRI in this work overlap with the reported QTLs associated with biomass under drought in alfalfa. Additional significant markers were targeted to several contigs with unknown chromosomal locations. BLAST search using their flanking sequences revealed homology to several annotated genes with functions in stress tolerance. With further validation, these markers may be used for marker-assisted breeding new alfalfa varieties with drought resistance and enhanced water use efficiency. 相似文献
997.
Angel J. Rivera Rebecca M. Stumpf Brenda Wilson Steve Leigh Abigail A. Salyers 《American journal of primatology》2010,72(6):467-474
The bacterial population of the primate vaginal canal is an infant primate's first exposure to the microbial population inhabiting the outside world. Yet, little is known about this population and the effect it might have on the development and survival of the infant primate. As a first step toward characterizing the vaginal microbiota of a nonhuman primate, we used denaturing gradient gel electrophoresis to evaluate variations in the vaginal microbiota of a group of 35 baboons (Papio hamadryas), which were housed in a facility where they shared the same diet and the same environmental conditions. We found that, despite the uniform environment, there were appreciable differences in the composition of the microbiota from one individual to another. Our results also indicate that a simple swab test is sufficient for sampling the vaginal microbiota in the field, a finding that should help make more detailed characterization of the microbiota of wild primates feasible in the future. Am. J. Primatol. 72:467–474, 2010. © 2010 Wiley‐Liss, Inc. 相似文献
998.
Tissue and cellular distribution of the extended family of protein kinase C isoenzymes 总被引:19,自引:0,他引:19
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W C Wetsel W A Khan I Merchenthaler H Rivera A E Halpern H M Phung A Negro-Vilar Y A Hannun 《The Journal of cell biology》1992,117(1):121-133
Polyclonal isoenzyme-specific antisera were developed against four calcium-independent protein kinase C (PKC) isoenzymes (delta, epsilon, epsilon', and zeta) as well as the calcium-dependent isoforms (alpha, beta I, beta II, and gamma). These antisera showed high specificities, high titers, and high binding affinities (3-370 nM) for the peptide antigens to which they were raised. Each antiserum detected a species of the predicted molecular weight by Western blot that could be blocked with the immunizing peptide. PKC was sequentially purified from rat brain, and the calcium-dependent forms were finally resolved by hydroxyapatite chromatography. Peak I reacted exclusively with antisera to PKC gamma, peak II with PKC beta I and -beta II, and peak III with PKC alpha. These same fractions, however, were devoid of immunoreactivity for the calcium-independent isoenzymes. The PKC isoenzymes demonstrated a distinctive tissue distribution when evaluated by Western blot and immunocytochemistry. PCK delta was present in brain, heart, spleen, lung, liver, ovary, pancreas, and adrenal tissues. PKC epsilon was present in brain, kidney, and pancreas, whereas PKC epsilon' was present predominantly in brain. PKC zeta was present in most tissues, particularly the lung, brain, and liver. Both PKC delta and PKC zeta showed some heterogeneity of size among the different tissues. PKC alpha was present in all organs and tissues examined. PKC beta I and -beta II were present in greatest amount in brain and spleen. Although the brain contained the most PKC gamma immunoreactivity, some immunostaining was also seen in adrenal tissue. These studies provide the first evidence of selective organ and tissue distributions of the calcium-independent PKC isoenzymes. 相似文献
999.
M. Rivera Feng Qiu Richard A. Bunce Ruth E. Stark 《Journal of biological inorganic chemistry》1999,4(1):87-98
Singly and doubly labeled δ-aminolevulinic acid derivatives were used to prepare rat liver outer mitochondrial membrane (OM)
cytochrome b
5 containing a 13C-labeled heme active site. A variety of NMR experiments, including HMBC and INADEQUATE in conjunction with the more commonly
used HMQC, NOESY, and COSY, were conducted to make unambiguous assignments of protonated carbons and the quaternary pyrrole-α
and -β carbons in both isomeric forms of the paramagnetic active center of OM cytochrome b
5. Because the long interpulse delays in the HMBC experiment have a detrimental effect on the detectability of fast relaxing
paramagnetically affected resonances, INADEQUATE is proposed as the experiment of choice for assigning quaternary carbons
in paramagnetic hemes with carefully chosen macrocycle labeling patterns. Furthermore, the applicability of the INADEQUATE
experiment to paramagnetic heme active sites should be facilitated greatly by the availability of biosynthetic methods for
producing isotopically labeled b-hemes and, more recently, isotopically labeled c-hemes.
Received: 21 September 1998 / Accepted: 25 November 1998 相似文献