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Advances and perspectives in the generation of polyploid plant species

MARIA CONCEPCION TAMAYO ORDOÑEZ LAURA ANGELICA ESPINOSA BARRERA YAHAIRA DE JESUS TAMAYO ORDOÑEZ BENJAMIN ABRAHAM AYIL GUTIERREZ LORENZO FELIPE SANCHEZ TEYER (2016)

Whole-genome duplication (polyploidy) occurs frequently and repeatedly within species of plants. According to the source of the genomes giving origin to a polyploid plant species, these are classified into allopolyploid (when two or more genomes are combined through either intraspecific or interspecific hybridization) and autopolyploid (when a single genome becomes duplicated). According to the time period in which polyploidy occurred plant species are classified as paleopolyploid (ancient polyploids), mesopolyploid (less ancient polyploids), and neopolyploid (recent polyploids). Many plant species appearing as diploid are actually paleopolyploids (ancient polyploids) derived from at least one event of whole-genome duplication followed by a process known as diploidization, which consists in massive gene loss and genomic reorganization (diploidized paleopolyploids). Many polyploid species of plants have been shown to present morphological and physiological characteristics making them further attractive for industry than their lower ploidy level counterparts. Polyploidy is a fundamental but relatively underexplored biological process. With the aim of understanding the factors involved in the formation of polyploid plant species, many studies have been carried out on synthetic polyploidy obtained by mitotic inhibitors and hybridization. However, the rapid progress of genetic engineering techniques makes genetic modification (GM) to become a feasible strategy for obtaining polyploid plants. In this review we discuss advancesmade about factors known to influence plant polyploidy and we suggest that in a future, this knowledge could be used for generating polyploids in vitro by GM and for crop improvement.

Article

CELL CYCLE MITOSIS AND MEIOSIS PLANTS POLYPLOIDY BIOLOGÍA Y QUÍMICA BIOLOGÍA Y QUÍMICA

Advances and perspectives in the generation of polyploid plant species

MARIA CONCEPCION TAMAYO ORDOÑEZ LAURA ANGELICA ESPINOSA BARRERA YAHAIRA DE JESUS TAMAYO ORDOÑEZ BENJAMIN ABRAHAM AYIL GUTIERREZ LORENZO FELIPE SANCHEZ TEYER (2016)

Whole-genome duplication (polyploidy) occurs frequently and repeatedly within species of plants. According to the source of the genomes giving origin to a polyploid plant species, these are classified into allopolyploid (when two or more genomes are combined through either intraspecific or interspecific hybridization) and autopolyploid (when a single genome becomes duplicated). According to the time period in which polyploidy occurred plant species are classified as paleopolyploid (ancient polyploids), mesopolyploid (less ancient polyploids), and neopolyploid (recent polyploids). Many plant species appearing as diploid are actually paleopolyploids (ancient polyploids) derived from at least one event of whole-genome duplication followed by a process known as diploidization, which consists in massive gene loss and genomic reorganization (diploidized paleopolyploids). Many polyploid species of plants have been shown to present morphological and physiological characteristics making them further attractive for industry than their lower ploidy level counterparts. Polyploidy is a fundamental but relatively underexplored biological process. With the aim of understanding the factors involved in the formation of polyploid plant species, many studies have been carried out on synthetic polyploidy obtained by mitotic inhibitors and hybridization. However, the rapid progress of genetic engineering techniques makes genetic modification (GM) to become a feasible strategy for obtaining polyploid plants. In this review we discuss advancesmade about factors known to influence plant polyploidy and we suggest that in a future, this knowledge could be used for generating polyploids in vitro by GM and for crop improvement.

Article

CELL CYCLE MITOSIS AND MEIOSIS PLANTS POLYPLOIDY BIOLOGÍA Y QUÍMICA

Abiotic stress response in plants: integrative genetic pathways and overlapping reactions between abiotic and biotic stress responses

SAUL FRAIRE VELAZQUEZ (2012)

In all ecosystems, plants continuously face environmental stress and consequently are forced to respond with defensive and adaptive strategies. These responses require the activation of several signaling pathways that induce expression of specific genes. An effective response requires that the biological system have the genetic background to support the necessary molecular players that permit the assembly of essential integrative genetic pathways. In the most complicated scenario, plants must contend against more than one abiotic stress, pest, or pathogen at the same time, forcing an integral and complete defense response to adjust plant physiology. Certain molecular players act as hubs or master regulators to integrate signals from The exclusive license for this PDF is limited to personal website use only. No part of this digital document may be reproduced, stored in a retrieval system or transmitted commercially in any form or by any means. The publisher has taken reasonable care in the preparation of this digital document, but makes no expressed or implied warranty of any kind and assumes no responsibility for any errors or omissions. No liability is assumed for incidental or consequential damages in connection with or arising out of information contained herein. This digital document is sold with the clear understanding that the publisher is not engaged in rendering legal, medical or any other professional services. Saúl Fraire-Velázquez, Lenin Sánchez-Calderón et al. 134 different regulatory pathways activated by two or more types of abiotic stress or forms of biotic stress. Some defense and adaptive genes are transcriptionally regulated not only by a specific abiotic stress but also by biotic stress, exposing the existence of overlapping pathways. The genes shared between these networks appear to allow plants to prioritize their responses and ensure their survival by using their resources efficiently. The well-documented shared or convergence points in the response to abiotic and biotic stress in plants exhibit a superimposed complexity, as exemplified by induction of certain defense genes by biotic stress in presence only of a specific environmental condition (temperature and humidity). Interestingly, accumulating data strongly support the hypothesis that the convergence points between abiotic and biotic stress pathways also modulate the post-embryonic developmental program which is one of the most conspicuous adaptive strategies to cope with environmental stress. Pathogen attack or abiotic stresses such as nutrient scarcity alter cell division and cell differentiation processes, and consequently the plant architecture is modified. Plant growth regulators, such as auxins, cytokinins, ethylene, and jamonic acid, as well as reactive oxygen species, play crucial roles in the early steps of the convergence between these multiple stress signals. The advancement in powerful molecular tools, including transcriptome and proteome analysis, whole-genome sequencing, and bioinformatic studies are enabling disection of networks in abiotic and biotic signaling cascades and identification of the overlapping reactions and key factors that fulfill very important roles as integrative signals in plants.

Producción Científica de la Universidad Autónoma de Zacatecas UAZ

Book part

BIOLOGÍA Y QUÍMICA Abiotic stress plants integrative genetic pathways overlapping reactions biotic

β-Carotene Production under Greenhouse Conditions

RODRIGO CASTAÑEDA MIRANDA LUIS OCTAVIO SOLIS SANCHEZ (2009)

β-carotene is a secondary metabolite that is a hydrocarbon carotene predominantly

located in lower concentrations in PS II functioning as a helper to harvest light pigment

during photosynthesis and to dissipate excess energy before damage occurs. As other

carotenes, β-carotene is uniquely synthesized in plants, algae, fungi and bacteria. βcarotene is the main diet precursor of pro-vitamin A. Additionally, β-carotene serves as

an essential nutrient and is in high demand in the market as a natural food colouring

agent, as an additive to cosmetics and also as a health food. Several approaches have

been carried out in order to increase β-carotene production in algae, bacteria, fungi and

plants using biotechnological and engineering focuses. In the case of plants, such species

as the tomato have important β-carotene contents, which are theoretically amenable to

management using approaches such as fertilization, growth conditions and mild stress.

On the other hand, greenhouse structures can protect crops from wind and rain, and can

also protect from insects when fitted with insect exclusion screens. β-carotene production

could potentially be improved and enhanced in greenhouse conditions in plants as well as in algae, based on the exclusion of the structure, and the possibility of controlling aspects

such as climate, fertilization and stress management, among others. Production of βcarotene (and other secondary metabolites) from several organisms in greenhouse

conditions should be an interesting future approach, visualizing the greenhouse as a

“factory” in frontier technologies such as biotechnology and mechatronics in order to

optimize this production.

Producción Científica de la Universidad Autónoma de Zacatecas UAZ

Book part

BIOLOGÍA Y QUÍMICA β-carotene photosynthesis plants

Revision of Begomovirus taxonomy based on pairwise sequence comparisons

JUDITH K. BROWN JESUS NAVAS CASTILLO ENRIQUE MORIONES ROBERTO RAMOS SOBRINHO JOSE C. F. SILVA ELVIRA FIALLO OLIVE ROB W. BRIDDON CECILIA HERNANDEZ ZEPEDA Ali Idris V. G. MALATHI RAFAEL FRANCISCO RIVERA BUSTAMANTE SHIGENORI UEDA Arvind Varsani (2015)

Viruses of the genus Begomovirus (family Geminiviridae) are emergent pathogens of crops throughout the tropical and subtropical regions of the world. By virtue of having a small DNA genome that is easily cloned, and due to the recent innovations in cloning and low-cost sequencing, there has been a dramatic increase in the number of available begomovirus genome sequences. Even so, most of the available sequences have been obtained from cultivated plants and are likely a small and phylogenetically unrepresentative sample of begomovirus diversity, a factor constraining taxonomic decisions such as the establishment of operationally useful species demarcation criteria. In addition, problems in assigning new viruses to established species have highlighted shortcomings in the previously recommended mechanism of species demarcation. Based on the analysis of 3,123 full-length begomovirus genome (or DNA-A component) sequences available in public databases as of December 2012, a set of revised guidelines for the classification and nomenclature of begomoviruses are proposed. The guidelines primarily consider a) genus-level biological characteristics and b) results obtained using a standardized classification tool, Sequence Demarcation Tool, which performs pairwise sequence alignments and identity calculations. These guidelines are consistent with the recently published recommendations for the genera Mastrevirus and Curtovirus of the family Geminiviridae. Genome-wide pairwise identities of 91 % and 94 % are proposed as the demarcation threshold for begomoviruses belonging to different species and strains, respectively. Procedures and guidelines are outlined for resolving conflicts that may arise when assigning species and strains to categories wherever the pairwise identity falls on or very near the demarcation threshold value.

Article

BEGOMOVIRUS GENOME, VIRAL PHYLOGENY PLANT DISEASES PLANTS SEQUENCE ALIGNMENT BIOLOGÍA Y QUÍMICA BIOLOGÍA Y QUÍMICA

An alternative strategy for targeted gene replacement in plants using a dual-sgRNA/Cas9 design

Song Gaoyuan Yunbi Xu (2016)

Precision DNA/gene replacement is a promising genome-editing tool that is highly desirable for molecular engineering and breeding by design. Although the CRISPR/Cas9 system works well as a tool for gene knockout in plants, gene replacement has rarely been reported. Towards this end, we first designed a combinatory dual-sgRNA/Cas9 vector (construct #1) that successfully deleted miRNA gene regions (MIR169a and MIR827a). The deletions were confirmed by PCR and subsequent sequencing, yielding deletion efficiencies of 20% and 24% on MIR169a and MIR827a loci, respectively. We designed a second structure (construct #2) that contains sites homologous to Arabidopsis TERMINAL FLOWER 1 (TFL1) for homology-directed repair (HDR) with regions corresponding to the two sgRNAs on the modified construct #1. The two constructs were co-transformed into Arabidopsis plants to provide both targeted deletion and donor repair for targeted gene replacement by HDR. Four of 500 stably transformed T0 transgenic plants (0.8%) contained replaced fragments. The presence of the expected recombination sites was further confirmed by sequencing. Therefore, we successfully established a gene deletion/replacement system in stably transformed plants that can potentially be utilized to introduce genes of interest for targeted crop improvement.

Article

Genes Plants CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA

Revision of Begomovirus taxonomy based on pairwise sequence comparisons

JUDITH K. BROWN JESUS NAVAS CASTILLO ENRIQUE MORIONES ROBERTO RAMOS SOBRINHO JOSE C. F. SILVA ELVIRA FIALLO OLIVE ROB W. BRIDDON CECILIA HERNANDEZ ZEPEDA Ali Idris V. G. MALATHI RAFAEL FRANCISCO RIVERA BUSTAMANTE SHIGENORI UEDA Arvind Varsani (2015)

Viruses of the genus Begomovirus (family Geminiviridae) are emergent pathogens of crops throughout the tropical and subtropical regions of the world. By virtue of having a small DNA genome that is easily cloned, and due to the recent innovations in cloning and low-cost sequencing, there has been a dramatic increase in the number of available begomovirus genome sequences. Even so, most of the available sequences have been obtained from cultivated plants and are likely a small and phylogenetically unrepresentative sample of begomovirus diversity, a factor constraining taxonomic decisions such as the establishment of operationally useful species demarcation criteria. In addition, problems in assigning new viruses to established species have highlighted shortcomings in the previously recommended mechanism of species demarcation. Based on the analysis of 3,123 full-length begomovirus genome (or DNA-A component) sequences available in public databases as of December 2012, a set of revised guidelines for the classification and nomenclature of begomoviruses are proposed. The guidelines primarily consider a) genus-level biological characteristics and b) results obtained using a standardized classification tool, Sequence Demarcation Tool, which performs pairwise sequence alignments and identity calculations. These guidelines are consistent with the recently published recommendations for the genera Mastrevirus and Curtovirus of the family Geminiviridae. Genome-wide pairwise identities of 91 % and 94 % are proposed as the demarcation threshold for begomoviruses belonging to different species and strains, respectively. Procedures and guidelines are outlined for resolving conflicts that may arise when assigning species and strains to categories wherever the pairwise identity falls on or very near the demarcation threshold value.

Article

BEGOMOVIRUS GENOME, VIRAL PHYLOGENY PLANT DISEASES PLANTS SEQUENCE ALIGNMENT BIOLOGÍA Y QUÍMICA

Abiotic stress response in plants: integrative genetic pathways and overlapping reactions between abiotic and biotic stress responses

SAUL FRAIRE VELAZQUEZ (2012)

In all ecosystems, plants continuously face environmental stress and consequently are forced to respond with defensive and adaptive strategies. These responses require the activation of several signaling pathways that induce expression of specific genes. An effective response requires that the biological system have the genetic background to support the necessary molecular players that permit the assembly of essential integrative genetic pathways. In the most complicated scenario, plants must contend against more than one abiotic stress, pest, or pathogen at the same time, forcing an integral and complete defense response to adjust plant physiology. Certain molecular players act as hubs or master regulators to integrate signals from The exclusive license for this PDF is limited to personal website use only. No part of this digital document may be reproduced, stored in a retrieval system or transmitted commercially in any form or by any means. The publisher has taken reasonable care in the preparation of this digital document, but makes no expressed or implied warranty of any kind and assumes no responsibility for any errors or omissions. No liability is assumed for incidental or consequential damages in connection with or arising out of information contained herein. This digital document is sold with the clear understanding that the publisher is not engaged in rendering legal, medical or any other professional services. Saúl Fraire-Velázquez, Lenin Sánchez-Calderón et al. 134 different regulatory pathways activated by two or more types of abiotic stress or forms of biotic stress. Some defense and adaptive genes are transcriptionally regulated not only by a specific abiotic stress but also by biotic stress, exposing the existence of overlapping pathways. The genes shared between these networks appear to allow plants to prioritize their responses and ensure their survival by using their resources efficiently. The well-documented shared or convergence points in the response to abiotic and biotic stress in plants exhibit a superimposed complexity, as exemplified by induction of certain defense genes by biotic stress in presence only of a specific environmental condition (temperature and humidity). Interestingly, accumulating data strongly support the hypothesis that the convergence points between abiotic and biotic stress pathways also modulate the post-embryonic developmental program which is one of the most conspicuous adaptive strategies to cope with environmental stress. Pathogen attack or abiotic stresses such as nutrient scarcity alter cell division and cell differentiation processes, and consequently the plant architecture is modified. Plant growth regulators, such as auxins, cytokinins, ethylene, and jamonic acid, as well as reactive oxygen species, play crucial roles in the early steps of the convergence between these multiple stress signals. The advancement in powerful molecular tools, including transcriptome and proteome analysis, whole-genome sequencing, and bioinformatic studies are enabling disection of networks in abiotic and biotic signaling cascades and identification of the overlapping reactions and key factors that fulfill very important roles as integrative signals in plants.

Producción Científica de la Universidad Autónoma de Zacatecas UAZ

Book part

BIOLOGÍA Y QUÍMICA Abiotic stress plants integrative genetic pathways overlapping reactions biotic

Isotopic Niche Variation in a Higher Trophic Level Ectotherm: Highlighting the Role of Succulent Plants in Desert Food Webs

Miguel Delibes MARIA DEL CARMEN BLAZQUEZ MORENO (2015)

"Stable isotope analysis of animal tissues allows description of isotopic niches, whose axes in an n-dimensional space are the isotopic ratios, compared to a standard, of different isotope systems (e.g. δ13C, δ15N). Isotopic niches are informative about where an animal, population or species lives and about what it consumes. Here we describe inter- and intrapopulation isotopic niche (bidimensional δ13C-δ15N space) of the Orange-throated whiptail (Aspidoscelis hyperythra), an arthropodivorous small lizard, in ten localities of Baja California Sur (Mexico). These localities range from extreme arid to subtropical conditions. Between 13 and 20 individuals were sampled at each locality and 1 cm of tail-tip was collected for isotope analysis. As expected, interpopulation niche width variation was much larger than intrapopulation one. Besides, isotopic variation was not related to age, sex or individual size of lizards. This suggests geographic variation of the isotopic niche was related to changes in the basal resources that fuel the trophic web at each locality. The position of Bayesian isotope ellipses in the δ-space indicated that whiptails in more arid localities were enriched in 13C, suggesting most of the carbon they ingested came from CAM succulent plants (cacti, agaves) and in minor degree in C4 grasses. Contrarily, whiptails in subtropical areas were depleted in 13C, as they received more carbon from C3 scrubs and trees. Localities closer to sea-level tended to be enriched in 15N, but a clear influence of marine subsidies was detected only at individual level. The study contributes to identify the origin and pathways through which energy flows across the trophic webs of North American deserts."

Article

Succulent Plants BIOLOGÍA Y QUÍMICA CIENCIAS DE LA VIDA BIOLOGÍA VEGETAL (BOTÁNICA) ECOLOGÍA VEGETAL

La cenicilla del rosal (Podosphaera pannosa)

DANIEL DOMINGUEZ SERRANO ROMULO GARCIA VELASCO MARTHA ELENA MORA HERRERA (2016)

Articulo de revisión, sobre el estado actual de Podosphaera pannosa

En México la rosa (Rosa sp.) es una especie ornamental con importancia económica y una de las más demandadas; entre las enfermedades que la afectan destaca la cenicilla. Esta enfermedad es causada por el biótrofo Podosphaera pannosa y repercute en la productividad, calidad, comercialización y costos de producción. Entre los fungicidas empleados para el control de la enfermedad destacan los inhibidores de la desmetilación y de la biosíntesis del ergosterol, y las estrobilurinas que inhiben la respiración mitocondrial. Algunos de estos fungicidas pierden su eficacia debido a la resistencia que va adquiriendo el patógeno. El desarrollo del patógeno está condicionado por diferentes aspectos bioecológicos y la variabilidad genética; a pesar de que se cuenta con un grupo amplio de medidas, genéticas y biológicas, su control es insuficiente. Actualmente, una alternativa es utilizar inductores de resistencia, como fosfito de potasio, silicio y acibenzolar-s-metil, contra patógenos como Peronospora sparsa y P. pannosa en el cultivo de rosa. En este ensayo se analizó la información actual de la cenicilla del rosal y proporciona perspectivas para estudios futuros de la enfermedad.

Universidad Autónoma del Estado de México

Article

podosphaera pannosa erysiphales ornamental plants CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA