Project description:Granule-bound starch synthase I (GBSSI) is responsible for Waxy gene encoding the, which is involved in the amylose synthesis step of starch biosynthesis. We investigated the genotypic and haplotypic variations of GBSSI (Os06g0133000) gene, including its evolutionary relatedness in the nucleotide sequence level using single-nucleotide polymorphisms (SNPs), indels, and structural variations (SVs) from 475 Korean World Rice Collection (KRICE_CORE), which comprised 54 wild rice and 421 cultivated represented by 6 ecotypes (temperate japonica, indica, tropical japonica, aus, aromatic, and admixture) or in another way by 3 varietal types (landrace, weedy, and bred). The results revealed that 27 of 59 haplotypes indicated a total of 12 functional SNPs (fSNPs), identifying 9 novel fSNPs. According to the identified novel fSNPs, we classified the entire rice collection into three groups: cultivated, wild, and mixed (cultivated and wild) rice. Five novel fSNPs were localized in wild rice: four G/A fSNPs in exons 2, 9, and 12 and one T/C fSNP in exon 13. We also identified the three previously reported fSNPs, namely, a G/A fSNP (exon 4), an A/C fSNP (exon 6), and a C/T fSNP (exon 10), which were observed only in cultivated rice, whereas an A/G fSNP (exon 4) was observed exclusively in wild rice. All-against-all comparison of four varietal types or six ecotypes of cultivated rice with wild rice showed that the GBSSI diversity was higher only in wild rice (π = 0.0056). The diversity reduction in cultivated rice can be useful to encompass the origin of this gene GBSSI during its evolution. Significant deviations of positive (wild and indica under balancing selection) and negative (temperate and tropical japonica under purifying selection) Tajima's D values from a neutral model can be informative about the selective sweeps of GBSSI genome insights. Despite the estimation of the differences in population structure and principal component analysis (PCA) between wild and subdivided cultivated subgroups, an inbreeding effect was quantified by F ST statistic, signifying the genetic relatedness of GBSSI. Our findings of a novel wild fSNPS can be applicable for future breeding of waxy rice varieties. Furthermore, the signatures of selective sweep can also be of informative into further deeper insights during domestication.
Project description:Phenotypic evaluation and efficient utilization of germplasm collections can be time-intensive, laborious, and expensive. However, with the plummeting costs of next-generation sequencing and the addition of genomic selection to the plant breeder's toolbox, we now can more efficiently tap the genetic diversity within large germplasm collections. In this study, we applied and evaluated genomic prediction's potential to a set of 482 pea (Pisum sativum L.) accessions-genotyped with 30,600 single nucleotide polymorphic (SNP) markers and phenotyped for seed yield and yield-related components-for enhancing selection of accessions from the USDA Pea Germplasm Collection. Genomic prediction models and several factors affecting predictive ability were evaluated in a series of cross-validation schemes across complex traits. Different genomic prediction models gave similar results, with predictive ability across traits ranging from 0.23 to 0.60, with no model working best across all traits. Increasing the training population size improved the predictive ability of most traits, including seed yield. Predictive abilities increased and reached a plateau with increasing number of markers presumably due to extensive linkage disequilibrium in the pea genome. Accounting for population structure effects did not significantly boost predictive ability, but we observed a slight improvement in seed yield. By applying the best genomic prediction model (e.g., RR-BLUP), we then examined the distribution of genotyped but nonphenotyped accessions and the reliability of genomic estimated breeding values (GEBV). The distribution of GEBV suggested that none of the nonphenotyped accessions were expected to perform outside the range of the phenotyped accessions. Desirable breeding values with higher reliability can be used to identify and screen favorable germplasm accessions. Expanding the training set and incorporating additional orthogonal information (e.g., transcriptomics, metabolomics, physiological traits, etc.) into the genomic prediction framework can enhance prediction accuracy.
Project description:The haplotype map constructed by the International HapMap Project is a valuable source for the studies of disease genes, population structure, and evolution. In the Project, haplotypes have been inferred from experimentally determined genotypes, and are fairly accurate for Caucasians and Africans since the inference was based on the genotypes of trios. However, the inference for the Asians populations was less accurate, because of the lack of familial information. Here we assessed how the error in the inference can affect downstream studies, especially the analysis of recent positive selections, by comparing the results of the analyses using the data of HapMap JPT and of definitive haplotypes (DHaplo-DB) determined by us from a collection of Japanese complete hydatidiform moles (CHM), each of which carries a genome derived from a single sperm. We found that the error in JPT was not uniform throughout the genome, and the statistics for recent positive selection was significantly affected. Keywords: Definitive haplotype determination using CHMs, which carry haploid genomes.
Project description:Opn3/TMT opsins belong to one of the opsin groups with vertebrate visual and non-visual opsins, and are widely distributed in eyes, brains and other internal organs in various vertebrates and invertebrates. Vertebrate Opn3/TMT opsins are further classified into four groups on the basis of their amino acid identities. However, there is limited information about molecular properties of these groups, due to the difficulty in preparing the recombinant proteins. Here, we successfully expressed recombinant proteins of TMT1 and TMT2 opsins of medaka fish (Oryzias latipes) in cultured cells and characterized their molecular properties. Spectroscopic and biochemical studies demonstrated that TMT1 and TMT2 opsins functioned as blue light-sensitive Gi/Go-coupled receptors, but exhibited spectral properties and photo-convertibility of the active state different from each other. TMT1 opsin forms a visible light-absorbing active state containing all-trans-retinal, which can be photo-converted to 7-cis- and 9-cis-retinal states in addition to the original 11-cis-retinal state. In contrast, the active state of TMT2 opsin is a UV light-absorbing state having all-trans-retinal and does not photo-convert to any other state, including the original 11-cis-retinal state. Thus, TMT opsins are diversified so as to form a different type of active state, which may be responsible for their different functions.
Project description:The haplotype map constructed by the International HapMap Project is a valuable source for the studies of disease genes, population structure, and evolution. In the Project, haplotypes have been inferred from experimentally determined genotypes, and are fairly accurate for Caucasians and Africans since the inference was based on the genotypes of trios. However, the inference for the Asians populations was less accurate, because of the lack of familial information. Here we assessed how the error in the inference can affect downstream studies, especially the analysis of recent positive selections, by comparing the results of the analyses using the data of HapMap JPT and of definitive haplotypes (DHaplo-DB) determined by us from a collection of Japanese complete hydatidiform moles (CHM), each of which carries a genome derived from a single sperm. We found that the error in JPT was not uniform throughout the genome, and the statistics for recent positive selection was significantly affected. Keywords: Definitive haplotype determination using CHMs, which carry haploid genomes. 100 CHM samples collected throughout Japan were analyzed by Affymetrix Genechip Mapping 500K Set array.
Project description:Data reported here is associated with the article entitled "TMT-based quantitative membrane proteomics identified pattern recognition receptors (PRRs) potentially involved in the perception of MSP1 in rice leaves" [1]. PAMP-triggered immunity (PTI) constitutes the first layer of plant innate immunity against pathogen infection. M. oryzae secreted protein MSP1 has been identified as a PAMP which induces PTI responses in rice. However, identification of PRRs involved in the recognition of MSP1 has not been achieved so far. In this manuscript, we carried out comprehensive proteomic profiling to investigate the potential PRRs and MSP1 induced signaling cascades using MSP1 overexpressed transgenic rice by TMT-labeling based quantitative analysis with QExactiveTM Orbitrap High-Resolution Mass Spectrometer [1].
Project description:The γ-oryzanol contents and the composition of steryl ferulates distributed in Japanese pigmented rice varieties were investigated using the high-performance liquid chromatography-ultraviolet detection method for the purpose of expanding their utilisation. The average γ-oryzanol content in nine black-purple, four red, four green and three brown rice varieties was 54.2, 47.3, 44.3 and 43.3 mg γ-oryzanol equivalent/100 g dried weight, respectively. Among the nine varieties of black-purple rice, five varieties showed steryl ferulate composition similar to that of brown, red and green varieties. In contrast, the composition of steryl ferulates in other four black-purple rice varieties was partially specific and was characterised by a low amount of campesteryl ferulate and high of campestanyl ferulate and stigmastanyl ferulate. The latter two steryl ferulates have been recognised as minor components of γ-oryzanol in rice and as major components in wheat and corn. These results indicate that the compositions of steryl ferulates vary among Japanese black-purple rice varieties.
Project description:A core collection is a subset that represents genetic diversity of the total collection. Soybean (Glycine max (L.) Merr.) is one of major food and feed crops. It is the world's most cultivated annual herbaceous legume. Constructing a core collection for soybean could play a pivotal role in conserving and utilizing its genetic variability for research and breeding programs. To construct and evaluate a Korean soybean core collection, genotypic and phenotypic data as well as population structure, were analyzed. The Korean soybean core collection consisted of 430 accessions selected from 2,872 collections based on Affymetrix Axiom® 180k SoyaSNP array data. The core collection represented 99% of genotypic diversity of the total collection. Analysis of population structure clustered the core collection into five subpopulations. Accessions from South Korea and North Korea were distributed across five subpopulations. Analysis of molecular variance indicated that only 2.01% of genetic variation could be explained by geographic origins while 16.18% of genetic variation was accounted for by subpopulations. Genome-wide association study (GWAS) for days to flowering, flower color, pubescent color, and growth habit confirmed that the core collection had the same genetic diversity for tested traits as the total collection. The Korean soybean core collection was constructed based on genotypic information of the 180k SNP data. Size and phenotypic diversity of the core collection accounted for approximately 14.9% and 18.1% of the total collection, respectively. GWAS of core and total collections successfully confirmed loci associated with tested traits. Consequently, the present study showed that the Korean soybean core collection could provide fundamental and practical material and information for both soybean genetic research and breeding programs.
Project description:To develop superior rice varieties with improved yield in most rainfed areas of Asia/Africa, we started an introgression-breeding program for simultaneously improving yield and tolerances of multiple abiotic stresses. Using eight BC1 populations derived from a widely adaptable recipient and eight donors plus three rounds of phenotypic selection, we developed 496 introgression lines (ILs) with significantly higher yield under drought, salt and/or non-stress conditions in 5 years. Six new varieties were released in the Philippines and Pakistan and many more are being evaluated in multi-location yield trials for releasing in several countries. Marker-facilitated genetic characterization revealed three interesting aspects of the breeding procedure: (1) the donor introgression pattern in specific BC populations was characteristic; (2) introgression frequency in different genomic regions varied considerably, resulting primarily from strong selection for the target traits; and (3) significantly lower heterozygosity was observed in BC progenies selected for drought and salinity tolerance. Applying strong phenotypic selection under abiotic stresses in early segregating generations has major advantages for not only improving multiple abiotic stress tolerance but also achieving quicker homozygosity in early generations. This breeding procedure can be easily adopted by small breeding programs in developing countries to develop high-yielding varieties tolerant of abiotic stresses. The large set of trait-specific ILs can be used for genetic mapping of genes/QTL that affect target and non-target traits and for efficient varietal development by designed QTL pyramiding and genomics-based recurrent selection in our Green Super Rice breeding technology.