RESUMEN

FLAVIN-BINDING, KELCH REPEAT, F-BOX 1 (FKF1) is a blue-light receptor whose function is related to flowering promotion under long-day conditions in Arabidopsis thaliana. However, information about the physiological role of FKF1 in day-neutral plants and even the physiological role other than photoperiodic flowering is lacking. Thus, the FKF1 homolog SlFKF1 was investigated in tomato, a day-neutral plant and a useful model for plants with fleshy fruit. It was confirmed that SlFKF1 belongs to the FKF1 group by phylogenetic tree analysis. The high sequence identity with A. thaliana FKF1, the conserved amino acids essential for function, and the similarity in the diurnal change in expression suggested that SlFKF1 may have similar functions to A. thaliana FKF1. CONSTANS (CO) is a transcription factor regulated by FKF1 and is responsible for the transcription of genes downstream of CO. cis-Regulatory elements targeted by CO were found in the promoter region of SINGLE FLOWER TRUSS (SFT) and RIN, which are involved in the regulation of flowering and fruit ripening, respectively. The blue-light effects on SlFKF1 expression, flowering, and fruit lycopene concentration have been observed in this study and previous studies. It was confirmed in RNA interference lines that the low expression of SlFKF1 is associated with late flowering with increased leaflets and low lycopene concentrations. This study sheds light on the various physiological roles of FKF1 in plants.

Asunto(s)

Frutas/metabolismo , Regulación del Desarrollo de la Expresión Génica , Regulación de la Expresión Génica de las Plantas , Proteínas de Plantas/metabolismo , Solanum lycopersicum/fisiología , Secuencia de Aminoácidos , Flores/crecimiento & desarrollo , Frutas/crecimiento & desarrollo , Licopeno/metabolismo , Fotoperiodo , Proteínas de Plantas/genética , Plantas Modificadas Genéticamente , Regiones Promotoras Genéticas/genética , Interferencia de ARN , Homología de Secuencia de Aminoácido , Factores de Transcripción/metabolismo

RESUMEN

The Ca2+/cation antiporter (CaCA) superfamily plays an important role in the regulation of the essential element Ca2+ and cation concentrations. Characterization and expression analyses of CaCA superfamily genes were performed in the tomato (Solanum lycopersicum) as a representative of dicotyledonous plants and fruit crops. Sixteen CaCA candidate genes were found and identified as tomato CaCA, SlCaCA, by a domain search. In a phylogenetic analysis of the SlCaCA superfamily, the 16 genes were classified into SlCAX, SlNCL, SlCCX, and SlMHX families. Among them, Solyc12g011070, belonging to the SlCAX family, had four splice variants, three of which were predicted to be nonfunctional because of a lack of important motifs. EF-hand domains were only found in SlNCL, in addition to consensus Na_Ca_ex domains, and the region containing EF-hand domains was characteristically long in some members of SlNCL. Furthermore, four genes of the SlCCX family were found to be intronless. As for intracellular localization, one SlCCX member was predicted to be localized to the plasma membrane, while other SlCCXs, SlCAXs, and SlMHXs were predicted to be localized to the vacuolar membrane. The expression patterns of SlCaCAs in various organs, including during several developmental stages of fruit, were classified into four groups. Genes involved in each of the SlCAX, SlNCL, and SlCCX gene families were categorized into three or four groups according to expression patterns, suggesting role sharing within each family. The main member in each subfamily and the members with characteristic fruit expression patterns included genes whose expression was regulated by sugar or auxin and that were highly expressed in a line having metabolite-rich fruit.

RESUMEN

We performed comparative metabolome and transcriptome analyses throughout fruit development using the tomato cultivar M82 and its near-isogenic line IL8-3, with interesting and useful traits such as a high content of soluble solids. Marked differences between M82 and IL8-3 were found not only in ripe fruits but also at 20 days after flowering (DAF) in the hierarchical clustering analysis of the metabolome, whereas patterns were similar between the two genotypes at 10 and 30 DAF. Our metabolome analysis conclusively showed that 20 DAF is an important stage of fruit metabolism and that the Solanum pennellii introgressed region in IL8-3 plays a key role in metabolic changes at this stage. Carbohydrate and amino acid metabolism were found to be promoted in IL8-3 at 20 DAF and the ripening stage, respectively, whereas transcriptome analysis showed no marked differences between the two genotypes, indicating that dynamic metabolic regulation at 20 DAF and the ripening stage was controlled by relatively few genes. The transcript levels of the cell wall invertase (LIN6) and sucrose synthase (TOMSSF) genes in starch and sucrose metabolic pathway and that of the glutamate synthase (SlGOGAT) gene in the amino acid metabolic pathway in IL8-3 fruit were higher than those in M82, and SlGOGAT expression was enhanced under high-sugar conditions. The results suggest that the promotion of carbohydrate metabolism by LIN6 and TOMSSF in IL8-3 fruit at 20 DAF affects SlGOGAT expression and amino acid accumulation via higher sugar concentration at the late stage of fruit development.

Asunto(s)

Cromosomas de las Plantas/metabolismo , Frutas/crecimiento & desarrollo , Frutas/metabolismo , Endogamia , Metaboloma , Solanum lycopersicum/crecimiento & desarrollo , Solanum lycopersicum/metabolismo , Aminoácidos/metabolismo , Metabolismo de los Hidratos de Carbono/genética , Análisis por Conglomerados , Frutas/genética , Perfilación de la Expresión Génica , Regulación de la Expresión Génica de las Plantas , Solanum lycopersicum/genética , Metabolómica , Análisis de Componente Principal , ARN Mensajero/genética , ARN Mensajero/metabolismo

RESUMEN

Enhancement of sugar content and sweetness is desirable in some vegetables and in almost all fruits; however, biotechnological methods to increase sugar content are limited. Here, a completely novel methodological approach is presented that produces sweeter tomato fruits but does not have any negative effects on plant growth. Sucrose-induced repression of translation (SIRT), which is mediated by upstream open reading frames (uORFs), was initially reported in Arabidopsis AtbZIP11, a class S basic region leucine zipper (bZIP) transcription factor gene. Here, two AtbZIP11 orthologous genes, SlbZIP1 and SlbZIP2, were identified in tomato (Solanum lycopersicum). SlbZIP1 and SlbZIP2 contained four and three uORFs, respectively, in the cDNA 5'-leader regions. The second uORFs from the 5' cDNA end were conserved and involved in SIRT. Tomato plants were transformed with binary vectors in which only the main open reading frames (ORFs) of SlbZIP1 and SlbZIP2, without the SIRT-responsive uORFs, were placed under the control of the fruit-specific E8 promoter. Growth and morphology of the resulting transgenic tomato plants were comparable to those of wild-type plants. Transgenic fruits were approximately 1.5-fold higher in sugar content (sucrose/glucose/fructose) than nontransgenic tomato fruits. In addition, the levels of several amino acids, such as asparagine and glutamine, were higher in transgenic fruits than in wild-type fruits. This was expected because SlbZIP transactivates the asparagine synthase and proline dehydrogenase genes. This 'sweetening' technology is broadly applicable to other plants that utilize sucrose as a major translocation sugar.

Asunto(s)

Factores de Transcripción con Cremalleras de Leucina de Carácter Básico/genética , Frutas/metabolismo , Plantas Modificadas Genéticamente/metabolismo , Solanum lycopersicum/fisiología , Sacarosa/metabolismo , Aminoácidos/metabolismo , Arabidopsis/genética , Factores de Transcripción con Cremalleras de Leucina de Carácter Básico/metabolismo , Fructosa/metabolismo , Frutas/genética , Regulación de la Expresión Génica de las Plantas , Glucosa/metabolismo , Solanum lycopersicum/genética , Solanum lycopersicum/crecimiento & desarrollo , Sistemas de Lectura Abierta , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Modificadas Genéticamente/genética , Regiones Promotoras Genéticas

RESUMEN

The aldo-keto reductase (AKR) superfamily is a large enzyme group of NADP-dependent oxidoreductases with numerous roles in metabolism, but many members in this superfamily remain uncharacterized. Here, PpAKR1, which was cloned from the rosaceous peach tree (Prunus persica), was investigated as a member of the superfamily. While PpAKR1 had amino acids that are important in AKRs and which belonged to the AKR4 group, PpAKR1 did not seem to belong to any of the AKR4 subgroups. PpAKR1 mRNA abundance increased with abscisic acid, oxidative stress, and cold and salt stress treatments in peach. NADP-dependent polyol dehydrogenase activity was increased in Arabidopsis thaliana transformed with PpAKR1. Salt tolerance increased in Arabidopsis transformed with PpAKR1. PpAKR1, which was a previously uncharacterized member of the AKR superfamily, could be involved in the abiotic stress tolerance.

Asunto(s)

Aldehído Reductasa/genética , Regulación de la Expresión Génica de las Plantas , Prunus/enzimología , Estrés Fisiológico , Aldehído Reductasa/metabolismo , Aldo-Ceto Reductasas , Secuencia de Aminoácidos , Arabidopsis/genética , Arabidopsis/fisiología , Frutas/enzimología , Frutas/genética , Frutas/fisiología , Expresión Génica , Regulación Enzimológica de la Expresión Génica , Genes Reporteros , L-Iditol 2-Deshidrogenasa/genética , L-Iditol 2-Deshidrogenasa/metabolismo , Datos de Secuencia Molecular , Especificidad de Órganos , Filogenia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Modificadas Genéticamente , Prunus/genética , Prunus/fisiología , Tolerancia a la Sal , Alineación de Secuencia

RESUMEN

Tomato (Solanum lycopersicum L.) plants were transformed with an antisense construct of a cDNA encoding tomato telomere-binding protein (LeTBP1) to describe the role of a telomere-binding protein at the whole plant level. Fruit size decreased corresponding to the degree of suppression of LeTBP1 expression. This inhibition of fruit development was likely due to a decrease in the number of seeds in the LeTBP1 antisense plants. Pollen fertility and pollen germination rate decreased in accordance with the degree of suppression of LeTBP1 expression. Ovule viability was also reduced in the LeTBP1 antisense plants. Although plant height was somewhat reduced in the antisense plants compared to the control plants, the number and weight of leaves were unaffected by LeTBP1 suppression. The number and morphology of flowers were also normal in the antisense plants. These indicate that reduced fertility in the antisense plants is not an indirect effect of altered vegetative growth. LeTBP1 expression was sensitive to temperature stress in wild-type plants. We conclude that LeTBP1 plays a critical role in seed and fruit development rather than vegetative growth and flower formation.

Asunto(s)

Frutas/crecimiento & desarrollo , Semillas/crecimiento & desarrollo , Solanum lycopersicum/fisiología , Supresión Genética/genética , Proteínas de Unión a Telómeros/genética , Cromosomas de las Plantas/genética , ADN sin Sentido/genética , ADN Complementario/genética , ADN de Plantas/genética , Flores/genética , Flores/crecimiento & desarrollo , Flores/fisiología , Frutas/genética , Frutas/fisiología , Expresión Génica/genética , Regulación de la Expresión Génica de las Plantas/genética , Solanum lycopersicum/citología , Solanum lycopersicum/genética , Solanum lycopersicum/crecimiento & desarrollo , Meristema/citología , Óvulo Vegetal/fisiología , Hojas de la Planta/genética , Hojas de la Planta/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Modificadas Genéticamente , Polen/fisiología , Semillas/genética , Semillas/fisiología , Estrés Fisiológico , Proteínas de Unión a Telómeros/metabolismo , Temperatura

RESUMEN

The effects of light quality on flowering time were investigated in Gypsophila paniculata, which is a long-day cut flower, and with Arabidopsis under long-day conditions with light-emitting diodes (LEDs). Gypsophila paniculata plants were grown under natural daylight and flowering was controlled by long-day treatment with a weak LED light of a single color in the night. Flowering was promoted not by blue light, but by far-red light in G. paniculata, while flowering was promoted by both light colors in Arabidopsis. FT homologs of G. paniculata GpFT1 and GpFT2 were differentially expressed under long-day conditions with white light, suggesting that they play roles in flowering at different stages of reproductive development. GpFTs and FT gene expression was not induced by far-red light in G. paniculata or Arabidopsis. Instead, the expression of the SOC1 homolog of G. paniculata GpSOC1 and SOC1 was induced by far-red light in G. paniculata and Arabidopsis. Flowering was promoted by induction of FT and SOC1 expression with blue light in Arabidopsis, whereas GpFTs and GpSOC1 expression was low with blue light induction in G. paniculata. The relationship between flowering and the expression of FT and SOC1 in Arabidopsis was confirmed with ft and soc1 mutants. These results suggest that long-day conditions with far-red light promote flowering through SOC1 and its homologs, while the conditions with blue light do not promote flowering in G. paniculata, because of low expression of GpFTs and GpSOC1 in contrast to that in Arabidopsis.

Asunto(s)

Proteínas de Arabidopsis/genética , Arabidopsis/fisiología , Caryophyllaceae/fisiología , Regulación de la Expresión Génica de las Plantas/efectos de la radiación , Proteínas de Dominio MADS/genética , Proteínas de Plantas/genética , Secuencia de Aminoácidos , Arabidopsis/genética , Arabidopsis/efectos de la radiación , Proteínas de Arabidopsis/efectos de la radiación , Caryophyllaceae/genética , Caryophyllaceae/efectos de la radiación , Clonación Molecular , ADN Complementario/genética , Flores/genética , Flores/fisiología , Flores/efectos de la radiación , Regulación del Desarrollo de la Expresión Génica , Genes de Plantas/genética , Luz , Iluminación , Proteínas de Dominio MADS/efectos de la radiación , Datos de Secuencia Molecular , Mutación , Fotoperiodo , Filogenia , Proteínas de Plantas/efectos de la radiación , Plantas Modificadas Genéticamente , Alineación de Secuencia , Factores de Tiempo