Common bentgrass Agrostis capillaris L. is known as tolerant to toxic elements. A hypothesis was examined that its ecotypes growing in historically polluted sites show a limited arsenic uptake and ...have genetic features that distinguish them from commercially available cultivars. The study was conducted in Złoty Stok, a historical area of arsenic mining. Additionally, two commercial cultivars were grown in pots with arsenic-rich soils. Based on arsenic concentrations in plant roots and shoots, bioconcentration and translocation factors BCF and TF were calculated. Commercial cultivars indicated many times higher BCF shoots and TF values compared to field plants. DNA analysis of leaf blades showed a clear distinction between the plants growing in some sites and patches in the field, and also a gene overlap between the plants in the field and commercial forms. The research did not allow for identification of ecotypes with exceptionally limited arsenic uptake. Moreover, there were no significant differences between the genotypic characteristics of plants growing in polluted sites and those poorly tolerant grown from commercially available seeds. Apparently, other factors, and not genetically determined features, are responsible for A. capillaris tolerance to arsenic in Złoty Stok.
Narrow-leafed lupin (NLL, Lupinus angustifolius L.) is a legume plant cultivated for grain production and soil improvement. Worldwide expansion of NLL as a crop attracted various pathogenic fungi, ...including Colletotrichum lupini causing a devastating disease, anthracnose. Two alleles conferring improved resistance, Lanr1 and AnMan, were exploited in NLL breeding, however, underlying molecular mechanisms remained unknown. In this study, European NLL germplasm was screened with Lanr1 and AnMan markers. Inoculation tests in controlled environment confirmed effectiveness of both resistance donors. Representative resistant and susceptible lines were subjected to differential gene expression profiling. Resistance to anthracnose was associated with overrepresentation of "GO:0006952 defense response", "GO:0055114 oxidation-reduction process" and "GO:0015979 photosynthesis" gene ontology terms. Moreover, the Lanr1 (83A:476) line revealed massive transcriptomic reprogramming quickly after inoculation, whereas other lines showed such a response delayed by about 42 h. Defense response was associated with upregulation of TIR-NBS, CC-NBS-LRR and NBS-LRR genes, pathogenesis-related 10 proteins, lipid transfer proteins, glucan endo-1,3-beta-glucosidases, glycine-rich cell wall proteins and genes from reactive oxygen species pathway. Early response of 83A:476, including orchestrated downregulation of photosynthesis-related genes, coincided with the successful defense during fungus biotrophic growth phase, indicating effector-triggered immunity. Mandelup response was delayed and resembled general horizontal resistance.
In this study transcriptome was analyzed on two fibrous varieties of flax: the susceptible Regina and the resistant Nike. The experiment was carried out on 2-week-old seedlings, because in this phase ...of development flax is the most susceptible to infection. We analyzed the whole seedlings, which allowed us to recognize the systemic response of the plants to the infection. We decided to analyze two time points: 24h and 48h, because our goal was to learn the mechanisms activated in the initial stages of infection, these points were selected based on the previous analysis of chitinase gene expression, whose increase in time of Fusarium oxysporum lini infection has been repeatedly confirmed both in the case of flax and other plant species. The results show that although qualitatively the responses of the two varieties are similar, it is the degree of the response that plays the role in the differences of their resistance to F. oxysporum.
Main conclusion
Upregulation of the terpenoid pathway and increased ABA content in flax upon
Fusarium
infection leads to activation of the early plant’s response (PR genes, cell wall remodeling, and ...redox status).
Plants have developed a number of defense strategies against the adverse effects of fungi such as
Fusarium oxysporum
. One such defense is the production of antioxidant secondary metabolites, which fall into two main groups: the phenylpropanoids and the terpenoids. While functions and biosynthesis of phenylpropanoids have been extensively studied, very little is known about the genes controlling the terpenoid synthesis pathway in flax. They can serve as antioxidants, but are also substrates for a plethora of different compounds, including those of regulatory functions, like ABA. ABA’s function during pathogen attack remains obscure and often depends on the specific plant-pathogen interactions. In our study we showed that in flax the non-mevalonate pathway is strongly activated in the early hours of pathogen infection and that there is a redirection of metabolites towards ABA synthesis. The elevated synthesis of ABA correlates with flax resistance to
F. oxysporum
, thus we suggest ABA to be a positive regulator of the plant’s early response to the infection.
White lupin (
L.) is a pulse annual plant cultivated from the tropics to temperate regions for its high-protein grain as well as a cover crop or green manure. Wild populations are typically late ...flowering and have high vernalization requirements. Nevertheless, some early flowering and thermoneutral accessions were found in the Mediterranean basin. Recently, quantitative trait loci (QTLs) explaining flowering time variance were identified in bi-parental population mapping, however, phenotypic and genotypic diversity in the world collection has not been addressed yet. In this study, a diverse set of white lupin accessions (
= 160) was phenotyped for time to flowering in a controlled environment and genotyped with PCR-based markers (
= 50) tagging major QTLs and selected homologs of photoperiod and vernalization pathway genes. This survey highlighted quantitative control of flowering time in white lupin, providing statistically significant associations for all major QTLs and numerous regulatory genes, including white lupin homologs of
,
,
,
,
,
, and
. This revealed the complexity of flowering control in white lupin, dispersed among numerous loci localized on several chromosomes, provided economic justification for future genome-wide association studies or genomic selection rather than relying on simple marker-assisted selection.
White lupin (Lupinus albus L.) is a high-protein Old World grain legume with remarkable food and feed production interest. It is sown in autumn or early spring, depending on the local agroclimatic ...conditions. This study aimed to identify allelic variants associated with vernalization responsiveness, in order to improve our knowledge of legume flowering regulatory pathways and develop molecular selection tools for the desired phenology as required for current breeding and adaptation to the changing climate. Some 120 white lupin accessions originating from a wide range of environments of Europe, Africa, and Asia were phenotyped under field conditions in three environments with different intensities of vernalization, namely, a Mediterranean and a subcontinental climate sites of Italy under autumn sowing, and a suboceanic climate site of France under spring sowing. Two hundred sixty-two individual genotypes extracted from them were phenotyped in a greenhouse under long-day photoperiod without vernalization. Phenology data, and marker data generated by Diversity Arrays Technology sequencing (DArT-seq) and by PCR-based screening targeting published quantitative trait loci (QTLs) from linkage map and newly identified insertion/deletion polymorphisms in the promoter region of the FLOWERING LOCUS T homolog, LalbFTc1 gene (Lalb_Chr14g0364281), were subjected to a genome-wide association study (GWAS). Population structure followed differences in phenology and isolation by distance pattern. The GWAS highlighted numerous loci significantly associated with flowering time, including four LalbFTc1 gene promoter deletions: 2388 bp and 2126 bp deletions at the 5' end, a 264 bp deletion in the middle and a 28 bp deletion at the 3' end of the promoter. Besides LalbFTc1 deletions, this set contained DArT-seq markers that matched previously published major QTLs in chromosomes Lalb_Chr02, Lalb_Chr13 and Lalb_Chr16, and newly discovered QTLs in other chromosomes. This study highlighted novel QTLs for flowering time and validated those already published, thereby providing novel evidence on the convergence of FTc1 gene functional evolution into the vernalization pathway in Old World lupin species. Moreover, this research provided the set of loci specific for extreme phenotypes (the earliest or the latest) awaiting further implementation in marker-assisted selection for spring- or winter sowing.
The regioselective hydroxylation of phenolic compounds, especially flavonoids, is still a bottleneck of classical organic chemistry that could be solved using enzymes with high activity and ...specificity. Yeast Rhodotorula glutinis KCh735 in known to catalyze the C-8 hydroxylation of flavones and flavanones. The enzyme F8H (flavonoid C8-hydroxylase) is involved in the reaction, but the specific gene has not yet been identified. In this work, we present identification, heterologous expression and characterization of the first F8H ortho-hydroxylase from yeast. Differential transcriptome analysis and homology to bacterial monooxygenases, including also a FAD-dependent motif and a GD motif characteristic for flavin-dependent monooxygenases, provided a set of coding sequences among which RgF8H was identified. Phylogenetic analysis suggests that RgF8H is a member of the flavin monooxygenase group active on flavonoid substrates. Analysis of recombinant protein showed that the enzyme catalyzes the C8-hydroxylation of naringenin, hesperetin, eriodyctiol, pinocembrin, apigenin, luteolin, chrysin, diosmetin and 7,4ʹ-dihydroxyflavone. The presence of the C7-OH group is necessary for enzymatic activity indicating ortho-hydroxylation mechanism. The enzyme requires the NADPH coenzyme for regeneration prosthetic group, displays very low hydroxyperoxyflavin decupling rate, and addition of FAD significantly increases its activity. This study presents identification of the first yeast hydroxylase responsible for regioselective C8-hydroxylation of flavonoids (F8H). The enzyme was biochemically characterized and applied in in vitro cascade with Bacillus megaterium glucose dehydrogenase reactions. High in vivo activity in Escherichia coli enable further synthetic biology application towards production of rare highly antioxidant compounds.
All living organisms on Earth evolved in the presence of an electromagnetic field (EMF), adapted to the environment of EMF, and even learned to utilize it for their purposes. However, during the last ...century, the Earth's core lost its exclusivity, and many EMF sources appeared due to the development of electricity and electronics. Previous research suggested that the EMF led to changes in intercellular free radical homeostasis and further altered the expression of genes involved in plant response to environmental stresses, inorganic ion transport, and cell wall constituent biosynthesis. Later, CTCT sequence motifs in gene promoters were proposed to be responsible for the response to EMF. How these motifs or different mechanisms are involved in the plant reaction to external EMF remains unknown. Moreover, as many genes activated under EMF treatment do not have the CTCT repeats in their promoters, we aimed to determine the transcription profile of a plant exposed to an EMF and identify the genes that are directly involved in response to the treatment to find the common denominator of the observed changes in the plant transcriptome.
The poultry industry is under pressure to produce safe and good quality meat in the welfare conditions. Many areas such as genetics, biosecurity, and immunoprophylaxis were improved, and hatchery is ...one of the areas in which welfare could be improved for better production output. The aim of the study was to investigate the effect of early post-hatch nutrition providing body weight and muscle development in broiler chickens. The experiment involving two groups (chicken hatched with access to water and feed in the hatcher, and chicken without feed and water in hatcher) was replicated three times, and the body weights and breast-muscle index of the randomly chosen 30 chickens per group in each term were measured on the 1st, 7th, 21st, and 35th day of life. The breast-muscle sample was taken for genetic examination (the expression of the myoD, myoG, and MRF4 genes) and histological examination. The results showed that the positive effect of early nutrition was observed on the seventh day of bird life with higher expression of myoG and MRF4 and higher body weight of the birds. The positive effect of early nutrition on the diameter of the breast-muscle fibers was visible on days 21 and 35 of chicken life. The average final body weight in groups with early access to food and water was 5% higher than in groups hatched under classic conditions. Conclusions: early feeding in the hatcher improves performance and muscle growth in broiler chickens.
Narrow-leafed lupin (
Lupinus angustifolius
L.) is a moderate-yielding legume crop known for its high grain protein content and contribution to soil improvement. It is cultivated under photoperiods ...ranging from 9 to 17 h, as a spring-sown (in colder locations) or as an autumn-sown crop (in warmer regions). Wild populations require a prolonged cold period, called vernalization, to induce flowering. The key achievement of
L. angustifolius
domestication was the discovery of two natural mutations (named
Ku
and
Jul
) conferring vernalization independence. These mutations are overlapping deletion variants in the promoter of
LanFTc1
, a homolog of the
Arabidopsis thaliana FLOWERING LOCUS T
(
FT
) gene. The third deletion, named here as
Pal
, was recently found in primitive germplasm. In this study, we genotyped
L. angustifolius
germplasm that differs in domestication status and geographical origin for
LanFTc1
alleles, which we then phenotyped to establish flowering time and vernalization responsiveness. The
Ku
and
Jul
lines were vernalization-independent and early flowering, wild (
ku
) lines were vernalization-dependent and late flowering, whereas
the Pal
line conferred intermediate phenotype. Three lines representing
ku
,
Pal
, and
Ku
alleles were subjected to gene expression surveys under 8- and 16-h photoperiods.
FT
homologs (
LanFTa1
,
LanFTa2
,
LanFTc1
, and
LanFTc2
) and some genes selected by recent expression quantitative trait loci mapping were analyzed. Expression profiles of
LanFTc1
and
LanAGL8
(
AGAMOUS-like 8
) matched observed differences in flowering time between genotypes, highlighted by high induction after vernalization in the
ku
line. Moreover, these genes revealed altered circadian clock control in
Pal
line under short days.
LanFD
(
FD
) and
LanCRLK1
(
CALCIUM/CALMODULIN-REGULATED RECEPTOR-LIKE KINASE 1
) were negatively responsive to vernalization in
Ku
and
Pal
lines but positively responsive or variable in
ku
, whereas
LanUGT85A2
(
UDP-GLUCOSYL TRANSFERASE 85A2
) was significantly suppressed by vernalization in all lines. Such a pattern suggests the opposite regulation of these gene pairs in the vernalization pathway.
LanCRLK1
and
LanUGT85A2
are homologs of
A. thaliana
genes involved in the
FLOWERING LOCUS C
(
FLC
) vernalization pathway. Lupins, like many other legumes, do not have any
FLC
homologs. Therefore, candidate genes surveyed in this study, namely
LanFTc1
,
LanAGL8, LanCRLK1
, and
LanUGT85A2
, may constitute anchors for further elucidation of molecular components contributing to vernalization response in legumes.
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