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1.
BMC Plant Biol ; 19(1): 390, 2019 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-31500571

RESUMO

BACKGROUND: The primary pigments in flowers are anthocyanins, the biosynthesis of which is mainly regulated by R2R3-MYBs. Muscari armeniacum is an ornamental garden plant with deep cobalt blue flowers containing delphinidin-based anthocyanins. An anthocyanin-related R2R3-MYB MaAN2 has previously been identified in M. armeniacum flowers; here, we also characterized a novel R2R3-MYB MaMybA, to determine its function and highlight similarities and differences between MaMybA and MaAN2. RESULTS: In this study, a novel anthocyanin-related R2R3-MYB gene was isolated from M. armeniacum flowers and functionally identified. A sequence alignment showed that MaMybA contained motifs typically conserved with MaAN2 and its orthologs. However, the shared identity of the entire amino acid sequence between MaMybA and MaAN2 was 43.5%. Phylogenetic analysis showed that they were both clustered into the AN2 subgroup of the R2R3-MYB family, but not in the same branch. We also identified a IIIf bHLH protein, MabHLH1, in M. armeniacum flowers. A bimolecular fluorescence complementation assay showed that MabHLH1 interacted with MaMybA or MaAN2 in vivo; a dual luciferase assay indicated that MaMybA alone or in interaction with MabHLH1 could regulate the expression of MaDFR and AtDFR, but MaAN2 required MabHLH1 to do so. When overexpressing MaMybA in Nicotiana tabacum 'NC89', the leaves, petals, anthers, and calyx of transgenic tobacco showed intense and magenta anthocyanin pigments, whereas those of OE-MaAN2 plants had lighter pigmentation. However, the ovary wall and seed skin of OE-MaMybA tobacco were barely pigmented, while those of OE-MaAN2 tobacco were reddish-purple. Moreover, overexpressing MaMybA in tobacco obviously improved anthocyanin pigmentation, compared to the OE-MaAN2 and control plants, by largely upregulating anthocyanin biosynthetic and endogenous bHLH genes. Notably, the increased transcription of NtF3'5'H in OE-MaMybA tobacco might lead to additional accumulation of delphinidin 3-rutinoside, which was barely detected in OE-MaAN2 and control plants. We concluded that the high concentration of anthocyanin and the newly produced Dp3R caused the darker color of OE-MaMybA compared to OE-MaAN2 tobacco. CONCLUSION: The newly identified R2R3-MYB transcription factor MaMybA functions in anthocyanin biosynthesis, but has some differences from MaAN2; MaMybA could also be useful in modifying flower color in ornamental plants.


Assuntos
Antocianinas/metabolismo , Asparagaceae/fisiologia , Regulação da Expressão Gênica de Plantas , Pigmentos Biológicos/genética , Proteínas de Plantas/genética , Tabaco/fisiologia , Fatores de Transcrição/genética , Sequência de Aminoácidos , Asparagaceae/genética , Asparagaceae/metabolismo , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Cor , Flores/genética , Flores/fisiologia , Filogenia , Pigmentos Biológicos/metabolismo , Proteínas de Plantas/química , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/metabolismo , Plantas Geneticamente Modificadas/fisiologia , Alinhamento de Sequência , Tabaco/genética , Tabaco/metabolismo , Fatores de Transcrição/química , Fatores de Transcrição/metabolismo
2.
BMC Plant Biol ; 19(1): 287, 2019 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-31262258

RESUMO

BACKGROUND: The majority of apricot (Prunus armeniaca L.) cultivars display orange or yellow background skin, whereas some cultivars are particularly preferred by consumers because of their red blushed skin on the background. RESULTS: In this study, two blushed ('Jianali' and 'Hongyu') and two nonblushed ('Baixing' and 'Luntaixiaobaixing') cultivars were used to investigate the formation mechanism of blushed skin in apricots. High-performance liquid chromatography (HPLC) analysis showed that the blushed cultivars accumulated higher cyanidin-3-O-glucoside, cyanidin-3-O-rutinoside and peonidin-3-O-rutinoside levels during fruit ripening than the nonblushed cultivars. Based on coexpression network analysis (WGCNA), a putative anthocyanin-related R2R3-MYB, PaMYB10, and seven structural genes were identified from transcriptome data. The phylogenetic analysis indicated that PaMYB10 clustered in the anthocyanin-related MYB clade. Sequence alignments revealed that PaMYB10 contained a bHLH-interaction motif ([DE]Lx2[RK]x3Lx6Lx3R) and an ANDV motif. Subcellular localization analysis showed that PaMYB10 was a nuclear protein. Real-time qRT-PCR analysis demonstrated that the transcript levels of PaMYB10 and seven genes responsible for anthocyanin synthesis were significantly higher in blushed than in nonblushed apricots, which was consistent with the accumulation of anthocyanin. In addition, bagging significantly inhibited the transcript levels of PaMYB10 and the structural genes in 'Jianali' and blocked the red coloration and anthocyanin accumulation. Transient PaMYB10 overexpression in 'Luntaixiaobaixing' fruits resulted in the red blushed skin at the maturation stage. CONCLUSIONS: Taken together, these data reveal that three anthocyanins are responsible for the blushed skin of apricots, identify PaMYB10 as a positive regulator of anthocyanin biosynthesis in apricots, and demonstrate that blush formation depends on light.


Assuntos
Antocianinas/biossíntese , Regulação da Expressão Gênica de Plantas , Pigmentos Biológicos/biossíntese , Proteínas de Plantas/genética , Prunus armeniaca/fisiologia , Fatores de Transcrição/genética , Sequência de Aminoácidos , Antocianinas/genética , Cromatografia Líquida de Alta Pressão , Cor , Frutas/genética , Frutas/fisiologia , Glucosídeos/biossíntese , Glucosídeos/genética , Filogenia , Pigmentos Biológicos/genética , Proteínas de Plantas/química , Proteínas de Plantas/metabolismo , Prunus armeniaca/genética , Alinhamento de Sequência , Fatores de Transcrição/química , Fatores de Transcrição/metabolismo
3.
Food Microbiol ; 82: 497-503, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31027811

RESUMO

Pseudomonas fluorescens Ps_77 is a blue-pigmenting strain able to cause food product discoloration, causing relevant economic losses especially in the dairy industry. Unlike non-pigmenting P. fluorescens, blue pigmenting strains previously were shown to carry a genomic region that includes homologs of trpABCDF genes, pointing at a possible role of the tryptophan biosynthetic pathway in production of the pigment. Here, we employ random mutagenesis to first identify the genes involved in blue-pigment production in P. fluorescens Ps_77 and second to investigate the biological function of the blue pigment. Genetic analyses based on the mapping of the random insertions allowed the identification of eight genes involved in pigment production, including the second copy of trpB (trpB_1) gene. Phenotypic characterization of Ps_77 white mutants demonstrated that the blue pigment increases oxidative-stress resistance. Indeed, while Ps_77 was growing at a normal rate in presence of 5 mM of H2O2, white mutants were completely inhibited. The antioxidative protection is not available for non-producing bacteria in co-culture with Ps_77.


Assuntos
Antioxidantes/metabolismo , Proteínas de Bactérias/metabolismo , Pigmentos Biológicos/metabolismo , Pseudomonas fluorescens/fisiologia , Proteínas de Bactérias/genética , Peróxido de Hidrogênio/metabolismo , Família Multigênica , Mutagênese , Mutação , Estresse Oxidativo , Pigmentos Biológicos/genética , Pseudomonas fluorescens/genética , Pseudomonas fluorescens/crescimento & desenvolvimento , Pseudomonas fluorescens/metabolismo
4.
Plant Physiol Biochem ; 138: 130-139, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30870763

RESUMO

The flower color of Paeonia 'Coral Sunset' and 'Pink Hawaiian Coral' changes from coral to pink to pale yellow during flowering, which confers high ornamental value to these two cultivars. However, the molecular mechanism underlying flower color change is still unclear. In this study, flavonoids in petals of Paeonia 'Coral Sunset' and 'Pink Hawaiian Coral' at seven flowering stages were analyzed to explore the effects of the flavonoid component on changes in flower color. In addition, four cDNA libraries of 'Coral Sunset' during the critical blooming stages were constructed and the transcriptome was sequenced to investigate the molecular mechanism underlying changes to flower color. Two anthocyanins (cyanidin-3,5-di-O-glucoside and peonidin-3,5-di-O-glucoside) were detected in both cultivars. Total anthocyanin content in both cultivars accumulated continuously from stages 1-3 and then decreased sharply. Correlation analysis showed that the change in flower color from coral to pink to pale yellow is due to a significant decrease in anthocyanin content. A total of 91,583 Unigenes were obtained in 'Coral Sunset', 33,962 (37.08%) of which were annotated to major databases. Based on the enrichment analysis of differentially expressed genes, eight structural genes (CHS, F3H, F3'H, FLS, DRF, ANS, ANR and UFGT) and 13 transcription factors (five MYB, three bHLH, one WD40, one HY5, one PIF3, one COP1 and two PHY) related to flavonoid biosynthesis were screened. The qRT-PCR results were generally consistent with the high-throughput sequencing results. This research will provide a foundation to clarify the mechanisms underlying changes in flower color of herbaceous peony.


Assuntos
Antocianinas , Flores , Perfilação da Expressão Gênica , Genes de Plantas , Paeonia , Pigmentação/genética , Pigmentos Biológicos , Antocianinas/biossíntese , Antocianinas/genética , Flores/genética , Flores/metabolismo , Paeonia/genética , Paeonia/metabolismo , Pigmentos Biológicos/biossíntese , Pigmentos Biológicos/genética
5.
PLoS One ; 14(1): e0209181, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30673708

RESUMO

The eggshell blueness is an interesting object for chicken genetic studies and blue-shelled chicken industry, especially after the discovery of the causative mutation of chicken blue eggshell. In the present study, genome wide association study (GWAS) was conducted in Chinese Dongxiang blue-shelled chicken underlying four traits of blue eggshell pigments: quantity of biliverdin (QB), quantity of protoporphyrin (QP), quantity of total pigment (QT), and color density trait (CD). A total of 139 individuals were randomly collected for GWAS. We detected two SNPs in genome-wise significance and 35 in suggestive significance, 24 out of the 37 SNP were located either within intron/exon or near 15 genes in a range of ~1.17 Mb on GGA21. For further confirmation of the identified SNP loci by GWAS, the follow-up replication studies were performed in two populations. A total of 146 individuals of the second generation derived from the former GWAS population, as well as 280 individuals from an alternative independent population were employed for genotyping by MALDI-TOF MS in a genotype-phenotype association study. Eighteen SNPs evenly distributed on the GGA21 significant region were successfully genotyped in the two populations, of which 4 and 6 SNP loci were shown significantly associated with QB, QT and QP in the two repeat populations, respectively. Further, the SNPs were narrowed down to a region of ~ 653.819 Kb on GGA21 that harbors five candidate genes: AJAP1, TNFRSF9, C1ORF174, CAMTA1, and CEP104. Shell gland of chickens laying dark and light blue eggshell was chosen for detection of mRNA expression of the five candidate genes. The results showed differential expression levels of these genes in the two groups. The specific function of these genes has not yet been defined clearly in chickens and further in-depth studies are needed to explore the new functional role in chicken eggshell blueness.


Assuntos
Galinhas/genética , Galinhas/metabolismo , Casca de Ovo/metabolismo , Pigmentação/genética , Animais , China , Cor , Feminino , Estudos de Associação Genética , Genética Populacional , Estudo de Associação Genômica Ampla/veterinária , Haplótipos , Pigmentos Biológicos/genética , Pigmentos Biológicos/metabolismo , Polimorfismo de Nucleotídeo Único , RNA Mensageiro/genética , Seleção Artificial/genética , Membro 1B3 da Família de Transportadores de Ânion Orgânico Carreador de Soluto/genética
6.
Anim Biotechnol ; 30(3): 273-278, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30638122

RESUMO

Melanocyte stimulating hormone receptor (MC1R) has been known as a regulator of eumelanin and phaeomelanin production in the melanocytes, and MC1R mutations causing coat color changes are known in many vertebrates; however, there are no research reports about the differentially expression of MC1R gene and its coding protein in Cashmere goats with different coat color. We examined the presence of MC1R distribution and MC1R protein and gene expression in the white Cashmere goats and black Cashmere goats, respectively; q-PCR, Western blot and immunhistochemical analysis showed that the expression of the MC1R gene in the black Cashmere goats was 3.39 fold more than the white ones (p < 0.01), and Cashmere goats with black genotype had significantly higher (2.03, p < 0.01) MC1R protein expression than white genotype in the all investigated samples. Moreover, all Cashmere goats with different coat color available for immunhistochemical analysis showed either lower (white Cashmere goats) or higher (black Cashmere goats) expression of the MC1R protein; these findings suggested that it had a relationship between the MC1R and the coat color of Cashmere goats. That could lay the foundation for the further research of the MC1R and coat color controllability regulation of the Cashmere goats.


Assuntos
Cabras/genética , Receptor Tipo 1 de Melanocortina/genética , Animais , Genótipo , Cabras/fisiologia , Imuno-Histoquímica/veterinária , Mutação , Pigmentação/genética , Pigmentos Biológicos/genética
7.
Animal ; 13(9): 1811-1816, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30614426

RESUMO

Although only a few specific pigmentation types are allowed within the Hucul horse registry, accurate determination of particular coat colors can be uncertain due to the presence of variation in color shades and segregation of multiple dun dilution variants. Herein, we genotyped the previously identified polymorphisms within two coat color loci TBX3 (T-box 3) and ASIP (Agouti Signaling Protein) in 462 Hucul individuals and compared the genotype predicted phenotypes with observed pigmentation types provided in the Polish Horse Breeders Association database. We identified disagreement between the predicted and recorded coat color in 157 horses (34%). The most common error was misclassification of horses with the nd1/nd1 and nd1/nd2 genotypes, what may be related with the occurrence of some 'intermediate' dilution phenotypes in such individuals. We have also proven that the frequency of the dominant dun dilution allele (D) (0.30) is higher than previously predicted by available studbooks. The D allele(s) is easily 'hidden' in various phenotypic groups including dark bay and black, therefore we hypothesized that the dun dilution effect itself is not as strongly epistatic in the Hucul horse as described in other horse breeds. This may be the result of an additional genetic modifier suppressing D allele phenotypic effect.


Assuntos
Proteína Agouti Sinalizadora/genética , Cavalos/genética , Pigmentação/genética , Pigmentos Biológicos/genética , Polimorfismo Genético/genética , Proteínas com Domínio T/genética , Alelos , Animais , Cruzamento , Feminino , Mutação da Fase de Leitura , Frequência do Gene , Genes Dominantes/genética , Genótipo , Técnicas de Genotipagem/veterinária , Cavalos/fisiologia , Masculino , Melaninas/metabolismo , Fenótipo , Receptor Tipo 1 de Melanocortina/genética
8.
Biotechnol Adv ; 37(1): 193-222, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30500354

RESUMO

Research on marine microalgae has been abundantly published and patented these last years leading to the production and/or the characterization of some biomolecules such as pigments, proteins, enzymes, biofuels, polyunsaturated fatty acids, enzymes and hydrocolloids. This literature focusing on metabolic pathways, structural characterization of biomolecules, taxonomy, optimization of culture conditions, biorefinery and downstream process is often optimistic considering the valorization of these biocompounds. However, the accumulation of knowledge associated with the development of processes and technologies for biomass production and its treatment has sometimes led to success in the commercial arena. In the history of the microalgae market, red marine microalgae are well positioned particularly for applications in the field of high value pigment and hydrocolloid productions. This review aims to establish the state of the art of the diversity of red marine microalgae, the advances in characterization of their metabolites and the developments of bioprocesses to produce this biomass.


Assuntos
Organismos Aquáticos/genética , Biocombustíveis , Biotecnologia/tendências , Microalgas/genética , Organismos Aquáticos/química , Biomassa , Enzimas/química , Enzimas/genética , Ácidos Graxos Insaturados/química , Ácidos Graxos Insaturados/genética , Redes e Vias Metabólicas/genética , Microalgas/química , Pigmentos Biológicos/química , Pigmentos Biológicos/genética
9.
Photosynth Res ; 140(3): 289-299, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30413987

RESUMO

The contents of photosynthetic pigments are an important indicator of many processes taking place in the plant body. Still, however, our knowledge of the effects of polyploidization, a major driver of speciation in vascular plants, on the contents of photosynthetic pigments is very sparse. We compared the contents of photosynthetic pigments among natural diploids, natural tetraploids, and synthetic tetraploids. The material originated from four natural mixed-cytotype populations of diploid and autotetraploid Vicia cracca (Fabaceae) occurring in the contact zone between the cytotypes in Central Europe and was cultivated under uniform conditions. We explored whether the contents of pigments are primarily driven by polyploidization or by subsequent evolution of the polyploid lineage and whether the patterns differ between populations. We also explored the relationship between pigment contents and plant performance. We found very few significant effects of the cytotype on the individual pigments but many significant interactions between the cytotype and the population. In pair-wise comparisons, many comparisons were not significant. The prevailing pattern among the significant once was that the contents of pigments were determined by polyploidization rather than by subsequent evolution of the polyploid lineage. The contents of the pigments turned out to be a useful predictor of plant performance not only at the time of material collection, but also at the end of the growing season. Further studies exploring differences in the contents of photosynthetic pigments in different cytotypes using replicated populations and assessing their relationship to plant performance are needed to assess the generality of our findings.


Assuntos
Fotossíntese/genética , Pigmentos Biológicos/genética , Vicia/genética , Diploide , Pigmentos Biológicos/metabolismo , Poliploidia , Tetraploidia , Vicia/fisiologia
10.
Biol Rev Camb Philos Soc ; 94(2): 388-414, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30152037

RESUMO

Aposematic theory has historically predicted that predators should select for warning signals to converge on a single form, as a result of frequency-dependent learning. However, widespread variation in warning signals is observed across closely related species, populations and, most problematically for evolutionary biologists, among individuals in the same population. Recent research has yielded an increased awareness of this diversity, challenging the paradigm of signal monomorphy in aposematic animals. Here we provide a comprehensive synthesis of these disparate lines of investigation, identifying within them three broad classes of explanation for variation in aposematic warning signals: genetic mechanisms, differences among predators and predator behaviour, and alternative selection pressures upon the signal. The mechanisms producing warning coloration are also important. Detailed studies of the genetic basis of warning signals in some species, most notably Heliconius butterflies, are beginning to shed light on the genetic architecture facilitating or limiting key processes such as the evolution and maintenance of polymorphisms, hybridisation, and speciation. Work on predator behaviour is changing our perception of the predator community as a single homogenous selective agent, emphasising the dynamic nature of predator-prey interactions. Predator variability in a range of factors (e.g. perceptual abilities, tolerance to chemical defences, and individual motivation), suggests that the role of predators is more complicated than previously appreciated. With complex selection regimes at work, polytypisms and polymorphisms may even occur in Müllerian mimicry systems. Meanwhile, phenotypes are often multifunctional, and thus subject to additional biotic and abiotic selection pressures. Some of these selective pressures, primarily sexual selection and thermoregulation, have received considerable attention, while others, such as disease risk and parental effects, offer promising avenues to explore. As well as reviewing the existing evidence from both empirical studies and theoretical modelling, we highlight hypotheses that could benefit from further investigation in aposematic species. Finally by collating known instances of variation in warning signals, we provide a valuable resource for understanding the taxonomic spread of diversity in aposematic signalling and with which to direct future research. A greater appreciation of the extent of variation in aposematic species, and of the selective pressures and constraints which contribute to this once-paradoxical phenomenon, yields a new perspective for the field of aposematic signalling.


Assuntos
Biodiversidade , Mimetismo Biológico/fisiologia , Variação Biológica da População , Pigmentos Biológicos/fisiologia , Comportamento Predatório/fisiologia , Fatores Etários , Animais , Evolução Biológica , Variação Biológica da População/genética , Ecossistema , Modelos Biológicos , Pigmentos Biológicos/genética , Polimorfismo Genético , Fatores Sexuais , Temperatura Ambiente
11.
Fish Physiol Biochem ; 45(1): 177-185, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30143930

RESUMO

Body color variation has long been a hot research topic in evolutionary and functional biology. Oujiang color common carp (Cyprinus carpio var. color) is a well-known economical and ornamental fish. Three main types of pigments and four distinct color patterns are typical characters of Oujiang color common carp, which makes it an excellent fish model to study body coloration. In this study, skin transcriptome assembly and comparisons were conducted in two Oujiang color common carp varieties: whole red and whole white. Transcriptome comparison revealed that more differentially expressed energy metabolism genes were upregulated in whole white compared to whole red. The results indicated that energy metabolism genes might be strongly associated with environmental adaption and growth performance and likely affect the red and white color formation in Oujiang color common carp. Our study provided direct guidance for the aquaculture industrials of Oujiang color common carp and presented valuable genetic resources for body color research in fish.


Assuntos
Carpas/fisiologia , Pigmentação da Pele/fisiologia , Transcriptoma , Animais , Pigmentos Biológicos/genética , Pigmentos Biológicos/metabolismo , RNA/genética , RNA/metabolismo , Pele/metabolismo
12.
Gene ; 689: 220-226, 2019 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-30572099

RESUMO

Meconopsis (Papaveraceae) is an interesting alpine herb, mainly distributed in the mountainous area of southwest China and high altitude zone in Tibetan-Himalaya. Different Meconopsis species showed a flower color alteration in different anthesis stages, Meconopsis 'Lingholm' is one of the localized species whose petal color changes from purple to blue during the flowering process. In general, the blue color flower is a rare kind, and usually hard to cultivate artificially. The molecular mechanism of flower color formation and color alteration of alpine flowers were reported by many research workers. To find critical genes that regulate Meconopsis 'Lingholm' color alteration and the mechanism of environmental adaptation, the current study performed transcriptome sequencing by using Meconopsis 'Lingholm' petals from different anthesis stages. There were totally 91,615 unigenes obtained from 31.4 Gb sequencing data, and differentially expressed genes between two consecutive flowering stages were obtained. Bioinformatics studies showed genes regulating petal color alteration were activated. Moreover, the functional analysis showed that Meconopsis 'Lingholm' showed a stress response to mechanical damage, non-biological stimulation and water deficiency in the bud stage, as well as showed a stress response to the cold from cracking stage to blooming stage. Furthermore, RNA-Seq results were verified using nine randomly selected genes by qPCR, which showed same expression trend with sequencing results. During this study, 20 candidate genes identified for further studies, which included five petal color related genes and 15 environmental response genes.


Assuntos
Flores/crescimento & desenvolvimento , Flores/genética , Papaveraceae/crescimento & desenvolvimento , Papaveraceae/genética , Pigmentos Biológicos/genética , Transcriptoma , Cor , Flores/metabolismo , Perfilação da Expressão Gênica , Regulação da Expressão Gênica no Desenvolvimento , Regulação da Expressão Gênica de Plantas , Interação Gene-Ambiente , Estudos de Associação Genética , Pigmentos Biológicos/metabolismo , Análise de Sequência de RNA , Sequenciamento Completo do Exoma
13.
Arch Insect Biochem Physiol ; 100(2): e21527, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30588650

RESUMO

Insect eye coloration arises from the accumulation of various pigments. A number of genes that function in the biosynthesis (vermilion, cinnabar, and cardinal) and importation (karmoisin, white, scarlet, and brown) of these pigments, and their precursors, have been identified in diverse species and used as markers for transgenesis and gene editing. To examine their suitability as visible markers in Lygus hesperus Knight (western tarnished plant bug), transcriptomic data were screened for sequences exhibiting homology with the Drosophila melanogaster proteins. Complete open reading frames encoding putative homologs for all seven genes were identified. Bioinformatic-based sequence and phylogenetic analyses supported initial annotations as eye coloration genes. Consistent with their proposed role, each of the genes was expressed in adult heads as well as throughout nymphal and adult development. Adult eyes of those injected with double-stranded RNAs (dsRNAs) for karmoisin, vermilion, cinnabar, cardinal, and scarlet were characterized by a red band along the medial margin extending from the rostral terminus to the antenna. In contrast, eyes of insects injected with dsRNAs for both white and brown were a uniform light brown. White knockdown also produced cuticular and behavioral defects. Based on its expression profile and robust visible phenotype, cardinal would likely prove to be the most suitable marker for developing gene editing methods in Lygus species.


Assuntos
Olho/metabolismo , Heterópteros/genética , Heterópteros/fisiologia , Pigmentação/genética , Pigmentos Biológicos/genética , Pigmentos Biológicos/fisiologia , Animais , Proteínas de Insetos/metabolismo , Interferência de RNA , RNA de Cadeia Dupla
14.
Mol Ecol ; 27(24): 5279-5293, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30565777

RESUMO

Cyanobacteria are important photoautotrophs in extreme environments such as the McMurdo Dry Valleys, Antarctica. Terrestrial Antarctic cyanobacteria experience constant darkness during the winter and constant light during the summer which influences the ability of these organisms to fix carbon over the course of an annual cycle. Here, we present a unique approach combining community structure, genomic and photophysiological analyses to understand adaptation to Antarctic light regimes in the cyanobacterium Leptolyngbya sp. BC1307. We show that Leptolyngbya sp. BC1307 belongs to a clade of cyanobacteria that inhabits near-surface environments in the McMurdo Dry Valleys. Genomic analyses reveal that, unlike close relatives, Leptolyngbya sp. BC1307 lacks the genes necessary for production of the pigment phycoerythrin and is incapable of complimentary chromatic acclimation, while containing several genes responsible for known photoprotective pigments. Photophysiology experiments confirmed Leptolyngbya sp. BC1307 to be tolerant of short-term exposure to high levels of photosynthetically active radiation, while sustained exposure reduced its capacity for photoprotection. As such, Leptolyngbya sp. BC1307 likely exploits low-light microenvironments within cyanobacterial mats in the McMurdo Dry Valleys.


Assuntos
Cianobactérias/genética , Cianobactérias/fisiologia , Fotossíntese , Filogenia , Adaptação Fisiológica , Regiões Antárticas , Genômica , Luz , Ficoeritrina/genética , Pigmentos Biológicos/genética
15.
Curr Biol ; 28(23): 3776-3786.e7, 2018 12 03.
Artigo em Inglês | MEDLINE | ID: mdl-30472000

RESUMO

A persistent question in evolutionary biology is how complex phenotypes evolve and whether phenotypic transitions are reversible. Multiple losses of floral pigmentation have been documented in the angiosperms, but color re-gain has not yet been described, supporting that re-gain is unlikely. Pollinator-mediated selection in Petunia has resulted in several color shifts comprised of both losses and gains of color. The R2R3-MYB transcription factor AN2 has been identified as a major locus responsible for shifts in pollinator preference. Whereas the loss of visible color has previously been attributed to repeated pseudogenization of AN2, here, we describe the mechanism of an independent re-gain of floral color via AN2 evolution. In P. secreta, purple color is restored through the improbable resurrection of AN2 gene function from a non-functional AN2-ancestor by a single reading-frame-restoring mutation. Thus, floral color evolution in Petunia is mechanistically dependent on AN2 functionality, highlighting its role as a hotspot in color transitions and a speciation gene for the genus.


Assuntos
Evolução Biológica , Petunia/genética , Pigmentos Biológicos/genética , Polinização , Flores/fisiologia , Especiação Genética , Petunia/fisiologia , Pigmentação/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
16.
Physiol Plant ; 164(4): 429-441, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30144090

RESUMO

Grapevine is one of the earliest domesticated fruit crops that has been widely prized and cultivated for its fruit and wine. Grapes exhibit a wide range of colors, ranging from the green/yellow to the dark blue tones according to the amount and composition of anthocyanin. During the last decades, many studies regarding the genetic control of the grape color in European, American and Asian cultivars have been well documented. DNA binding genes for several transcription factors, such as MYBA1 and MYBA2 haplotype compositions at the color locus are the key determinant of anthocyanin diversity and grape skin color development. Retrotransposon in the MYBA1 promoter region and mutation in MYBA2 coding sequence resulted in a white-skinned grape. The MYB haplotypes affect the ratio of tri/di-hydroxylated anthocyanins and methylated/non-methylated anthocyanins through the regulation of several structural genes involved in the anthocyanin biosynthesis, resulting in diverse colored tones. The present review provides an overview of the current state of the molecular mechanisms underlying the genetic regulations of the anthocyanin accumulation and diversification in grapes. The hypothesized models described in this review is a step forward to potentially predict the color diversification in different grape cultivars, which translate the advances in fundamental plant biology toward the application of grape molecular breeding.


Assuntos
Frutas/metabolismo , Agricultura Molecular/métodos , Pigmentos Biológicos/fisiologia , Vitis/fisiologia , Frutas/genética , Regulação da Expressão Gênica de Plantas/genética , Regulação da Expressão Gênica de Plantas/fisiologia , Pigmentos Biológicos/genética , Vitis/genética
17.
J Microbiol Biotechnol ; 28(7): 1068-1077, 2018 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-29975996

RESUMO

DKxanthenes are a class of yellow secondary metabolites produced by myxobacterial genera Myxococcus and Stigmatella. We identified a putative 49.5 kb DKxanthene biosynthetic gene cluster from Myxococcus stipitatus DSM 14675 by genomic sequence and mutational analysis. The cluster was comprisedof 15 genes (MYSTI_06004-MYSTI_06018) encoding polyketide synthases, non-ribosomal peptide synthases, and proteins with unknown functions. Disruption of the genes by plasmid insertion resulted in defects in the production of yellow pigments. High-performance liquid chromatography and liquid chromatography-tandem mass spectrometry analysis indicated that the yellow pigments produced by M. stipitatus DSM 14675 might be noble DKxanthene derivatives. M. stipitatus did not require DKxanthenes for the formation of heat-resistant viable spores, unlike Myxococcus xanthus. Furthermore, DKxanthenes showed growth inhibitory activity against the fungi Aspergillus niger, Candida albicans, and Rhizopus stolonifer.


Assuntos
Vias Biossintéticas/genética , Família Multigênica/genética , Myxococcus/enzimologia , Myxococcus/genética , Myxococcus/metabolismo , Xantenos/metabolismo , Xantenos/farmacologia , Anti-Infecciosos/química , Anti-Infecciosos/metabolismo , Anti-Infecciosos/farmacologia , Aspergillus niger/efeitos dos fármacos , Aspergillus niger/crescimento & desenvolvimento , Proteínas de Bactérias/genética , Candida albicans/efeitos dos fármacos , Candida albicans/crescimento & desenvolvimento , Carpóforos/efeitos dos fármacos , Genes Bacterianos/genética , Mutação , Myxococcus xanthus/metabolismo , Peptídeo Sintases/genética , Pigmentos Biológicos/genética , Pigmentos Biológicos/metabolismo , Plasmídeos/genética , Policetídeo Sintases/genética , Rhizopus/efeitos dos fármacos , Rhizopus/crescimento & desenvolvimento , Metabolismo Secundário/genética , Análise de Sequência , Esporos/efeitos dos fármacos , Xantenos/química
18.
Methods Mol Biol ; 1829: 341-365, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29987733

RESUMO

Since the time DNA was discovered as the code of life, genetic analysis has greatly advanced our understanding of the relation between genotype and phenotype and associated molecular mechanisms in various organisms including plants and algae. Forward genetics from phenotype to genotype has identified causal genes of interesting phenotypes induced by chemical, ionizing-radiation, or DNA insertional mutagenesis. Meanwhile, reverse genetics from genotype to phenotype has revealed physiological and molecular roles of known gene sequences. During the past dozen years, many molecular genetic tools have been developed to investigate gene functions quickly and efficiently. In this chapter, we introduce several approaches of forward and reverse genetics, including random chemical and DNA insertional mutagenesis, activation tagging, RNA interference, and gene overexpression and induction systems, with some examples of genetic studies of chloroplast biology mainly in Arabidopsis thaliana. We also briefly describe methods for chemical and DNA insertion mutagenesis and how to obtain sequence-tagged mutants from public collections. With greatly improved DNA sequencing and genome-editing technologies, model organisms as well as diverse species can be used for molecular biology. Genetic analysis can play an increasingly important role in elucidating chloroplast biogenesis and functions.


Assuntos
Arabidopsis/genética , Cloroplastos/genética , Técnicas Genéticas , Mutação , Arabidopsis/efeitos dos fármacos , Arabidopsis/efeitos da radiação , Clorofila/química , Elementos de DNA Transponíveis , Fluorescência , Regulação da Expressão Gênica de Plantas , Genes Reporter , Mutagênese Insercional , Mutagênicos/farmacologia , Pigmentos Biológicos/genética , Plantas/genética , Plantas Geneticamente Modificadas , Regiões Promotoras Genéticas , Interferência de RNA
19.
Zoolog Sci ; 35(3): 260-267, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29882491

RESUMO

Many species of ladybird beetles (Coccinellidae) possess vivid body colors. These colors and patterns show diversity between coccinellid species, or even within species. However, the molecular underpinnings of these striking body colors are scarcely understood. One of the candidate pigmentation molecules responsible for ladybird body color is ommochrome pigment, which is well known as the red pigment molecule responsible for the red eyes of Drosophila. Various insects also use ommochrome in body coloration. It is known that ommochrome pigment precursors are imported into appropriate cells by the ATP binding cassette (ABC) transporter proteins White and Scarlet. Thus, these ABC transporter genes are potentially involved in various color and pattern expressions seen in ladybird beetle species. In this study, in order to identify the repertory of ABC transporter genes responsible for such body colors, we performed molecular characterization of pigment-related ABC transporter genes, especially white and scarlet, in the coccinellid Harmonia axyridis. By using whole genome data for H. axyridis and subsequent RACE-PCR, six white orthologs and one scarlet ortholog were successfully identified. According to the results of functional analyses via RNA interference (RNAi), only one of these genes had a major function in eye pigmentation. Specific effects on body color and pattern were not detected by our RNAi experiments of any of these genes. This is the first report of this striking duplication of white genes and their functional analyses in insects.


Assuntos
Transportadores de Cassetes de Ligação de ATP/metabolismo , Besouros/fisiologia , Duplicação Gênica , Fenômenos Fisiológicos Oculares/genética , Pigmentação/genética , Pigmentos Biológicos/genética , Transportadores de Cassetes de Ligação de ATP/genética , Animais , Besouros/genética , Regulação da Expressão Gênica , Pigmentação/fisiologia
20.
New Phytol ; 219(1): 287-296, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29754447

RESUMO

The key enzymatic step in betalain biosynthesis involves conversion of l-3,4-dihydroxyphenylalanine (l-DOPA) to betalamic acid. One class of enzymes capable of this is 3,4-dihydroxyphenylalanine 4,5-dioxygenase (DODA). In betalain-producing species, multiple paralogs of this gene are maintained. This study demonstrates which paralogs function in the betalain pathway and determines the residue changes required to evolve a betalain-nonfunctional DODA into a betalain-functional DODA. Functionalities of two pairs of DODAs were tested by expression in beets, Arabidopsis and yeast, and gene silencing was performed by virus-induced gene silencing. Site-directed mutagenesis identified amino acid residues essential for betalamic acid production. Beta vulgaris and Mirabilis jalapa both possess a DODA1 lineage that functions in the betalain pathway and at least one other lineage, DODA2, that does not. Site-directed mutagenesis resulted in betalain biosynthesis by a previously nonfunctional DODA, revealing key residues required for evolution of the betalain pathway. Divergent functionality of DODA paralogs, one clade involved in betalain biosynthesis but others not, is present in various Caryophyllales species. A minimum of seven amino acid residue changes conferred betalain enzymatic activity to a betalain-nonfunctional DODA paralog, providing insight into the evolution of the betalain pigment pathway in plants.


Assuntos
Beta vulgaris/fisiologia , Betalaínas/biossíntese , Mutação com Ganho de Função , Proteínas de Plantas/genética , Arabidopsis/efeitos dos fármacos , Arabidopsis/genética , Arabidopsis/fisiologia , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Betalaínas/metabolismo , Caryophyllales/genética , Dioxigenases/genética , Dioxigenases/metabolismo , Evolução Molecular , Regulação da Expressão Gênica de Plantas , Levodopa/farmacocinética , Levodopa/farmacologia , Mirabilis/genética , Filogenia , Pigmentação/genética , Pigmentos Biológicos/biossíntese , Pigmentos Biológicos/genética , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas , Piridinas/metabolismo , Leveduras/genética
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