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Bolibok-Bragoszewska, H.

Publications and source records attributed to Bolibok-Bragoszewska, H..

3 recordsLinked to original sources

Phosphate transporter (Pht) gene families in rye (Secale cereale L.) - genome-wide identification and sequence diversity assessment

BackgroundPhosphorus is a macronutrient indispensable for plant growth and development. Plants utilize specialized transporters (PHT) to take up inorganic phosphorus and distribute it throughout the plant. The PHT transporters are divided into five families: PHT1 to PHT5. Each PHT family has a particular physiological and cellular function. Rye (Secale cereale L.) is a member of Triticeae, and an important source of variation for wheat breeding. It is considered to have the highest tolerance of nutrient deficiency, among Triticeae. To date, there is no report about genes involved in response to phosphorus deficiency in rye. The aim of this study was to: (i) identify and characterize putative members of different phosphate transporter families in rye, (i) assess their sequence diversity in a collection of diverse rye accessions via low-coverage resequencing (DArTreseq), and (iii) evaluate the expression of putative rye Pht genes under phosphate-deficient conditions. ResultsWe identified 29 and 35 putative Pht transporter genes in the rye Lo7 and Weining reference genomes, respectively, representing all known Pht families. Phylogenetic analysis revealed a close relationship of rye PHT with previously characterized PHT proteins from other species. Quantitative RT PCR carried out on leaf and root samples of Lo7 plants grown in Pi-deficient and control condition demonstrated that ScPht1;6, ScPht2 and ScPht3;1 are Pi-deficiency responsive. Based on DArTreseq genotyping of 94 diverse rye accessions we identified 820 polymorphic sites within rye ScPht, including 12 variants with a putatively deleterious effect. SNP density varied markedly between ScPht genes. ConclusionsThis report is the first step toward elucidating the mechanisms of ryes response to Pi deficiency. Our findings point to multiple layers of adaptation to local environments, ranging from gene copy number variation to differences in level of polymorphism across Pht family members. DArTreseq genotyping permits for a quick and cost-effective assessment of polymorphism levels across genes/gene families and supports identification and prioritization of candidates for further studies. Collectively our findings provide the foundation for selecting most promising candidates for further functional characterization.

genomics↗

Selective sweeps identification in distinct groups of cultivated rye (Secale cereale L.) germplasm provides potential candidates for crop improvement

BackgroundDuring domestication and subsequent improvement plants were subjected to intensive positive selection for desirable traits. Identification of selection targets is important with respect to the future targeted broadening of diversity in breeding programmes. Rye (Secale cereale L.) is a cereal that is closely related to wheat, and it is an important crop in Central, Eastern and Northern Europe. The aim of the study was (i) to identify diverse groups of rye accessions based on high-density, genome-wide analysis of genetic diversity within a set of 478 rye accessions, covering a full spectrum of diversity within the genus, from wild accession to inbred lines used in hybrid breeding, and (ii) to identify selective sweeps in the established groups of cultivated rye germplasm and putative candidate genes targeted by selection. ResultsPopulation structure and genetic diversity analyses based on high-quality SNP (DArTseq) markers revealed the presence of three complexes in the Secale genus: S. sylvestre, S. strictum and S. cereale/vavilovii, a relatively narrow diversity of S. sylvestre, very high diversity of S. strictum, and signatures of strong positive selection in S. vavilovii. Within cultivated ryes we detected the presence of genetic clusters and the influence of improvement status on the clustering. Rye landraces represent a reservoir of variation for breeding, and especially a distinct group of landraces from Turkey should be of special interest as a source of untapped variation. Selective sweep detection in cultivated accessions identified 133 outlier positions within 13 sweep regions and 170 putative candidate genes related, among others, to response to various environmental stimuli (such as pathogens, drought, cold), plant fertility and reproduction (pollen sperm cell differentiation, pollen maturation, pollen tube growth),and plant growth and biomass production. ConclusionsOur study provides valuable information for efficient management of rye germplasm collections, which can help to ensure proper safeguarding of their genetic potential and provides numerous novel candidate genes targeted by selection in cultivated rye for further functional characterisation and allelic diversity studies.

plant biology↗

Deep sampling and pooled amplicon sequencing reveals hidden genic variation in heterogeneous rye accessions

Loss of genetic variation negatively impacts breeding efforts and food security. Genebanks house over 7 million accessions representing vast allelic diversity that is a resource for sustainable breeding. Discovery of DNA variations is an important step in the efficient use of these resources. While technologies have improved and costs dropped, it remains impractical to consider resequencing millions of accessions. Candidate genes are known for most agronomic traits, providing a list of high priority targets. Heterogeneity in seed stocks means that multiple samples from an accession need to be evaluated to recover available alleles. To address this we developed a pooled amplicon sequencing approach and applied it to the out-crossing cereal rye (Secale cereale). Ninety-five rye accessions of different improvement status and worldwide origin, each represented by a pooled sample comprising DNA of 96 individual plants, were evaluated for sequence variation in six target genes involved in seed quality, biotic and abiotic stress resistance. Seventy-four predicted deleterious variants were identified using multiple algorithms. Rare variants were recovered including those found only in a low percentage of seed. A large extent of within-population heterogeneity was revealed, providing an important point for consideration during rye germplasm conservation and utilization efforts. We conclude that this approach provides a rapid and flexible method for evaluating stock heterogeneity, probing allele diversity, and recovering previously hidden variation.

genomics↗