Measurement of CP observables in B± → D(⁎)K± and B± → D(⁎)π± decays

Measurements of CP observables in B ± →D (⁎) K ± and B ± →D (⁎) π ± decays are presented, where D (⁎) indicates a neutral D or D ⁎ meson that is an admixture of D (⁎)0 and D¯ (⁎)0 states. Decays of the D ⁎ meson to the Dπ 0 and Dγ final states are partially reconstructed without inclusion of the neutral pion or photon, resulting in distinctive shapes in the B candidate invariant mass distribution. Decays of the D meson are fully reconstructed in the K ± π ∓ , K + K − and π + π − final states. The analysis uses a sample of charged B mesons produced in pp collisions collected by the LHCb experiment, corresponding to an integrated luminosity of 2.0, 1.0 and 2.0 fb −1 taken at centre-of-mass energies of s=7, 8 and 13 TeV, respectively. The study of B ± →D ⁎ K ± and B ± →D ⁎ π ± decays using a partial reconstruction method is the first of its kind, while the measurement of B ± →DK ± and B ± →Dπ ± decays is an update of previous LHCb measurements. The B ± →DK ± results are the most precise to date

First observation of forward Z→bbˉZ \rightarrow b \bar{b} production in pppp collisions at s=8\sqrt{s}=8 TeV

The decay Z→bb¯ is reconstructed in pp collision data, corresponding to 2 fb −1 of integrated luminosity, collected by the LHCb experiment at a centre-of-mass energy of s=8 TeV. The product of the Z production cross-section and the Z→bb¯ branching fraction is measured for candidates in the fiducial region defined by two particle-level b -quark jets with pseudorapidities in the range 2.220 GeV and dijet invariant mass in the range 4520$GeV and dijet invariant mass in the range$45 < m_{jj} < 165$GeV. From a signal yield of$5462 \pm 763$$Z \rightarrow b \bar{b}$events, where the uncertainty is statistical, a production cross-section times branching fraction of$332 \pm 46 \pm 59$pb is obtained, where the first uncertainty is statistical and the second systematic. The measured significance of the signal yield is 6.0 standard deviations. This measurement represents the first observation of the$Z \rightarrow b \bar{b}$production in the forward region of$pp$ collisions

Comparative genetic mapping between clementine, pummelo and sweet orange and the interspecicic structure of the clementine genome

The availability of a saturated genetic map of Clementine was identified by the International Citrus Genome Consortium as an essential prerequisite to assist the assembly of the reference whole genome sequence based on a Clementine derived haploid. The primary goals of the present study were to establish a Clementine reference map, and to perform comparative mapping with pummelo and sweet orange. Five parental genetic maps were established with SNPs, SSRs and InDels. A medium density reference map (961 markers for 1084.1 cM) of Clementine was established and used by the ICGC to facilitate the chromosome assembly of the haploid genome sequence. Comparative mapping with pummelo and sweet orange revealed that the linear order of markers was highly conserved. Reasonable inferences of most citrus genomes should be obtained by mapping next-generation sequencing data against the haploid reference genome sequence. Skewed segregations were frequent and higher in the male than female Clementine potentially leading to false interpretation of the genetic determinism of phenotypic traits. The mapping data confirmed that Clementine arose from hybridization between 'Mediterranean' mandarin and sweet orange and identified nine recombination break points for the sweet orange gamete that contributed to the Clementine genome. Introgression of pummelo genome fragments were identified in heterozygosity in each chromosome. Moreover, it appeared that the genome of the haploid Clementine used to establish the citrus reference genome sequence was inherited primarily from the 'Mediterranean' mandarin. The usefulness of this genetic map, anchored in the reference whole genome sequence, is discussed.Citrus Research and Development Foundation 108O568 Ministerio de Ciencia e Innovación: AGL2008-00596-MCI, 2008/121, IPT-010000-2010-43, PSE-060000-2009-8, AGL2007-65437-C04-01/AGR European Commission Citrus Research and Development Foundation itl-bio-03-10122 015453This work was principally funded by the French ANR CITRUSSEQ project. The European Commission, under the FP6-2003-INCO-DEV-2 project CIBEWU (n°015453), the Spanish Ministerio de Ciencia e Innovación grants, AGL2007-65437-C04-01/AGR and AGL2008-00596-MCI, the Spanish PSE-060000-2009-8 and IPT-010000-2010-43 projects, the Prometeo project 2008/121 Generalidad Valenciana, the Turkish TUBITAK Project No: 108O568; the California Citrus Research Board and UC Discovery grant itl-bio-03-10122 and the Florida Citrus Research and Development Foundation (CRDF), grants #67 and 71 also contributed to the work

A reference genetic map of C. clementina hort. ex Tan.; citrus evolution inferences from comparative mapping

PubMedID: 23126659Background: Most modern citrus cultivars have an interspecific origin. As a foundational step towards deciphering the interspecific genome structures, a reference whole genome sequence was produced by the International Citrus Genome Consortium from a haploid derived from Clementine mandarin. The availability of a saturated genetic map of Clementine was identified as an essential prerequisite to assist the whole genome sequence assembly. Clementine is believed to be a 'Mediterranean' mandarin × sweet orange hybrid, and sweet orange likely arose from interspecific hybridizations between mandarin and pummelo gene pools. The primary goals of the present study were to establish a Clementine reference map using codominant markers, and to perform comparative mapping of pummelo, sweet orange, and Clementine.Results: Five parental genetic maps were established from three segregating populations, which were genotyped with Single Nucleotide Polymorphism (SNP), Simple Sequence Repeats (SSR) and Insertion-Deletion (Indel) markers. An initial medium density reference map (961 markers for 1084.1 cM) of the Clementine was established by combining male and female Clementine segregation data. This Clementine map was compared with two pummelo maps and a sweet orange map. The linear order of markers was highly conserved in the different species. However, significant differences in map size were observed, which suggests a variation in the recombination rates. Skewed segregations were much higher in the male than female Clementine mapping data. The mapping data confirmed that Clementine arose from hybridization between 'Mediterranean' mandarin and sweet orange. The results identified nine recombination break points for the sweet orange gamete that contributed to the Clementine genome.Conclusions: A reference genetic map of citrus, used to facilitate the chromosome assembly of the first citrus reference genome sequence, was established. The high conservation of marker order observed at the interspecific level should allow reasonable inferences of most citrus genome sequences by mapping next-generation sequencing (NGS) data in the reference genome sequence. The genome of the haploid Clementine used to establish the citrus reference genome sequence appears to have been inherited primarily from the 'Mediterranean' mandarin. The high frequency of skewed allelic segregations in the male Clementine data underline the probable extent of deviation from Mendelian segregation for characters controlled by heterozygous loci in male parents. © 2012 Ollitrault et al.; licensee BioMed Central Ltd

Hyperacidification of <i>Citrus</i> fruits by a vacuolar proton-pumping P-ATPase complex

The sour taste of Citrus fruits is due to the extreme acidification of vacuoles in juice vesicle cells via a mechanism that remained elusive. Genetic analysis in petunia identified two vacuolar P-ATPases, PH1 and PH5, which determine flower color by hyperacidifying petal cell vacuoles. Here we show that Citrus homologs, CitPH1 and CitPH5, are expressed in sour lemon, orange, pummelo and rangpur lime fruits, while their expression is strongly reduced in sweet-tasting “acidless” varieties. Down-regulation of CitPH1 and CitPH5 is associated with mutations that disrupt expression of MYB, HLH and/or WRKY transcription factors homologous to those activating PH1 and PH5 in petunia. These findings address a long-standing enigma in cell biology and provide targets to engineer or select for taste in Citrus and other fruits

MARCADORES RAPD PARA MAPEAMENTO GENÉTICO E SELEÇÃO DE HÍBRIDOS DE CITROS RAPD MARKERS TO GENETIC MAPPING AND SELECTION OF CITRUS HYBRIDS

Os marcadores moleculares apresentam várias aplicações no melhoramento de plantas, permitindo uma série de análises genéticas. Este trabalho foi realizado com o objetivo de estabelecer marcadores RAPD para serem utilizados em estudos de mapeamento genético e na seleção de híbridos entre tangerina-'Cravo' (Citrus reticulata Blanco) e laranja-'Pêra' (C. sinensis (L.) Osbeck). Extraiu-se DNA de folhas dos parentais e de seis híbridos F1. As reações de amplificação foram preparadas em 13 uL de solução, constituída por tampão 1x GIBCO BRL; soluções 1,54 mM de MgCl2 e 0,2 mM de cada dNTP; 15 ng de cada 'primer'; 1,5 unidade de 'Taq DNA Polymerase' e 15 ng de DNA genômico. As reações foram realizadas em termocicladores programados para 36 ciclos de 1 min a 92ºC, 1 min a 36ºC, 2 min a 72ºC e 10 min de extensão a 72ºC. Foram testados 'primers' decâmeros arbitrários dos 'kits' A, AB, AT, AV, B, C, D, E, G, H, M, N, P, Q, R e U da Operon, sendo selecionados 113 por apresentarem polimorfismo, com número de marcadores variando de 1 a 6 por 'primer'. Esses 'primers' amplificaram 201 (23,13%) bandas polimórficas, aplicáveis no mapeamento genético e seleção de híbridos. A freqüência de 'primers' com 1; 2; 3; 4; 5 e 6 bandas polimórficas foi de 49,5%, 33,6%, 9,7%, 4,4%, 1,8% e 1,0%, respectivamente.<br>Molecular markers have many applications in plant breeding, enabling some types of genetic analyses. The aim of this work was to establish RAPD markers to be used to genetic mapping studies and selection of hybrids between 'Cravo' tangerine (Citrus reticulata Blanco) and 'Pêra' orange (C. sinensis (L.) Osbeck). DNA of the parents and six hybrids F1 was isolated from the leaves. The amplification reactions were performed in volumes of 13 µL, composed by GIBCO BRL 1x buffer, 1,54 mM MgCl2, 0,2 mM of each dNTP, 15 ng of each primer, 1,5 unit of Taq DNA Polymerase and 15 ng of genomic DNA. These reactions were carried out in thermocyclers programmed for 36 cycles of 1 min at 92ºC, 1 min at 36ºC, 2 min at 72ºC and 10 min of extension at 72ºC. It were evaluated random decamer primers of the kits A, AB, AT, AV, B, C, D, E, G, H, M, N, P, Q, R e U from Operon. One hundred thirteen primers were selected as polymorphics, with number of markers varying from 1 to 6 per primer. These primers amplified 201 (23,13%) polymorphic fragments, with application in genetic mapping and selection of hybrids. The frequency of primers with 1, 2, 3, 4, 5 and 6 polymorphic fragments was 49,5%, 33,6%, 9,7%, 4,4%, 1,8% e 1,0%, respectively

Detecção de polimorfismo em porta-enxertos para citros Detection of polimorphism in rootstocks for citrus

Objetivando a verificação da existência de plântulas originadas de embrião zigótico em viveiros comerciais de mudas cítricas, realizou-se o presente trabalho, utilizando a técnica de fAFLP e quatro espécies de porta-enxertos para citros. Verificou-se uma base genética estreita entre as espécies testadas, além de grande variabilidade entre os materiais, independentemente do viveiro em que foram coletados, o que permite concluir que a seleção visual, comumente realizada nos viveiros, é ineficiente.<br>The purpose of this work was to verify the existence of seedlings originated from the zygotic embryo, in commercial nurseries of citric seedlings. I was used the AFLP technique and four species of citrus rootstocks. It was observed a narrow genetic base among the tested species and also a great variability among the materials, independent of the nursery that they were collected. These results showed that the visual selection, commonly done in the nurseries, is inefficient

Diversidade genética entre híbridos de laranja-doce e tangor 'Murcott' avaliada por fAFLP e RAPD Genetic diversity among hybrids of sweet orange and 'Murcott' tangor evaluated by fAFLP and RAPD markers

O objetivo deste trabalho foi avaliar a diversidade genética em uma população de 148 híbridos de tangor 'Murcott' (Citrus reticulata Blanco x C. sinensis L. Osbeck) e laranja 'Pêra' (C. sinensis L. Osbeck) obtidos por polinização controlada, pelo uso de marcadores fAFLP e RAPD. Marcadores polimórficos (416 marcadores fAFLP e 33 RAPD) foram utilizados para avaliar a similaridade genética entre os híbridos, calculada com o coeficiente Jaccard pelo método UPGMA. A consistência de cada agrupamento foi determinada pelo programa BOOD. Houve alta similaridade genética entre os parentais. A laranja 'Pêra' apresentou maior número (132) de loci em heterozigose em relação ao tangor 'Murcott' (105), corroborando a teoria de origem híbrida para a laranja-doce. Observaram-se dois grupos distintos de plantas, e um deles abrangeu 80% dos híbridos com maior similaridade com a laranja 'Pêra'. A análise bootstrap não revelou consistência estatística entre esses grupos. Marcadores fAFLP são mais eficientes na avaliação do polimorfismo, sendo indicados para seleção de indivíduos híbridos mais próximos a um dos parentais.<br>The objective of this work was to evaluate the genetic diversity in a population of 148 hybrids of 'Murcott' tangor (Citrus reticulata Blanco x C. sinensis L. Osbeck) and 'Pêra' sweet orange (C. sinensis L. Osbeck), obtained by controlled polination, using fAFLP and RAPD markers. Polymorphic markers (416 fAFLP and 33 RAPD markers) were used to evaluate genetic similarity among the hybrids, calculated by the coefficient of Jaccard, using the UPGMA method. The consistency of each group was determined by software BOOD. There was high genetic similarity within the parents. 'Pêra' sweet orange had a higher number of loci in heterozygosis (132) compared to 'Murcott' tangor (105), supporting the theory of hybrid origin for sweet oranges. Two distinct groups of plants were observed: one group had 80% of the hybrids that displayed higher genetic similarity with 'Pêra' sweet orange. The bootstrap analysis did not show consistence between the groups. The fAFLP markers are more efficient to obtain polymorphism than RAPDs and are more suitable to select hybrids closer to the parents