Project description:The soybean (Glycine max) seed coat has distinctive, genetically programmed patterns of pigmentation and the recessive k1 mutation can epistatically overcome the dominant I and i-i alleles, which inhibit seed color by producing small interfering RNAs (siRNAs) targeting chalcone synthase (CHS) mRNAs. Small RNA sequencing of dissected regions of immature seed coats demonstrated that CHS siRNA levels cause the patterns produced by the i-i and i-k alleles of the I locus, which restrict pigment to the hilum or saddle region of the seed coat, respectively. To identify the K1 locus, we compared RNA-Seq data from dissected regions of two Clark isolines having similar saddle phenotypes mediated by CHS siRNAs but different genotypes (homozygous i-k K1 versus homozygous i-i k1). By examining differentially expressed genes, mapping information, and genome resequencing, we identified a 129-bp deletion in Glyma.11G190900 encoding Argonaute5 (AGO5), a member of the Argonaute family. Amplicon sequencing of several independent saddle pattern mutants from different genetic backgrounds revealed independent lesions affecting AGO5, thus establishing Glyma.11G190900 as the K1 locus. Non-functional AGO5 from k1 alleles leads to altered distributions of CHS siRNAs, thus explaining how the k1 mutation reverses the phenotype of the seed coat regions from yellow to pigmented, even in the presence of the normally dominant I or i-i alleles.
Project description:The soybean (Glycine max) seed coat has distinctive, genetically programmed patterns of pigmentation and the recessive k1 mutation can epistatically overcome the dominant I and i-i alleles, which inhibit seed color by producing small interfering RNAs (siRNAs) targeting chalcone synthase (CHS) mRNAs. Small RNA sequencing of dissected regions of immature seed coats demonstrated that CHS siRNA levels cause the patterns produced by the i-i and i-k alleles of the I locus, which restrict pigment to the hilum or saddle region of the seed coat, respectively. To identify the K1 locus, we compared RNA-Seq data from dissected regions of two Clark isolines having similar saddle phenotypes mediated by CHS siRNAs but different genotypes (homozygous i-k K1 versus homozygous i-i k1). By examining differentially expressed genes, mapping information, and genome resequencing, we identified a 129-bp deletion in Glyma.11G190900 encoding Argonaute5 (AGO5), a member of the Argonaute family. Amplicon sequencing of several independent saddle pattern mutants from different genetic backgrounds revealed independent lesions affecting AGO5, thus establishing Glyma.11G190900 as the K1 locus. Non-functional AGO5 from k1 alleles leads to altered distributions of CHS siRNAs, thus explaining how the k1 mutation reverses the phenotype of the seed coat regions from yellow to pigmented, even in the presence of the normally dominant I or i-i alleles.
Project description:The plant cell wall performs a number of essential functions including providing shape to many different cell types and serving as a defense against potential pathogens. The net pattern mutation creates breaks in the seed coat of soybean (Glycine max) because of ruptured cell walls. Using RNA-Seq, we examined the seed coat transcriptome from three stages of immature seed development in two pairs of isolines with normal or defective seed coat phenotypes due to the net pattern. The genome-wide comparative study of the transcript profiles of these isolines revealed 364 differentially expressed genes in common between the two varieties that were further divided into different broad functional categories. Genes related to cell wall processes accounted for 19% of the differentially expressed genes in the middle developmental stage of 100-200 mg seed weight. Within this class, the cell wall proline-rich and glycine-rich protein genes were highly differentially expressed in both genetic backgrounds. Other genes that showed significant expression changes in each of the isoline pairs at the 100-200 mg seed weight stage were xylem serine proteinase, fasciclin-related genes, auxin and stress response related genes, TRANSPARENT TESTA 1 (TT1) and other transcription factors. The mutant appears to shift the timing of either the increase or decrease in the levels of some of the transcripts. The analysis of these data sets reveals the physiological changes that the seed coat undergoes during the formation of the breaks in the cell wall. Examination of soybean isolines in two different genetic background at three different seed weight stages: Seed coats of Clark standard (CS, wild type) & Clark defective (CD, seed coat mutant), Harosoy Standard (HS) & Harosoy defective (HD) at 50-100mg, 100-200mg and 400-500mg.
Project description:With long-read assemblies, we delineate three origins of short interfering RNAs for chalcone synthase (CHS siRNAs) in Glycine max. Mutations from ii (yellow seed coat with black hilum) to i (fully pigmented) lack either a single antisense CHS1 gene by deletion or the partial 5’ subtilisin fragment-CHS1 gene region by a large inversion mutation. On the other hand, we show that the dominant I allele, with fully yellow seed coats, arose from the i black, wild soybean genome by an inverted duplication that places a partial 5’ DnaJ fragment next to slightly truncated CHS genes. In a direct I to i mutation, the two CHS genes are further truncated, destroying their capacity to produce siRNAs. The two-color saddle pattern of the ik allele arose by an inverted duplication event that places a partial 5’ P450 fragment in front of two inverted repeat CHS genes. Despite the importance of the three different 5’ promoters that abut inverted repeat CHS genes as drivers of precursor expression, the profiles of cognate gene family members for subtilisin, DnaJ, and P450 are not always limited to the seed coat as tightly as CHS siRNAs, implying that transcriptional or processing events for CHS dsRNA or siRNAs differ in other tissues.
2025-07-31 | GSE239923 | GEO
Project description:Glycine max (Clark, UC9, i mutation) genome resequencing
Project description:The seed coat of black (iRT) soybean with the dominant R allele begins to accumulate cyanic pigments at the transition stage of seed development (300 – 400 mg fresh seed weight), whereas the brown (irT) nearly-isogenic seed coat with the recessive r allele lacks cyanic pigments at all stages of seed development. We used microarrays to determine global gene expression differences between black (iRT) and brown (irT) soybean seed coats at the transition stage of seed development (300 – 400 mg fresh seed weight). To identify the complete set of gene transcripts that are differentially expressed between the seed coats of black (iRT) and brown (irT) Clark isolines, seed coats were dissected at the transition stage of seed development (300 – 400 mg fresh seed weight) for microarray analysis using the Affymetrix Soybean GeneChip. To ensure seed coats were of the same stage of development, the days post anthesis, pod length, pod color, embryo morphology, and transcript levels of the developmental marker gene Gm-r1083-1191, a putative cutin biosynthesis gene, and DFR1 were ensured to be equivalent between black (iRT) and brown (irT) isolines.
Project description:The plant cell wall performs a number of essential functions including providing shape to many different cell types and serving as a defense against potential pathogens. The net pattern mutation creates breaks in the seed coat of soybean (Glycine max) because of ruptured cell walls. Using RNA-Seq, we examined the seed coat transcriptome from three stages of immature seed development in two pairs of isolines with normal or defective seed coat phenotypes due to the net pattern. The genome-wide comparative study of the transcript profiles of these isolines revealed 364 differentially expressed genes in common between the two varieties that were further divided into different broad functional categories. Genes related to cell wall processes accounted for 19% of the differentially expressed genes in the middle developmental stage of 100-200 mg seed weight. Within this class, the cell wall proline-rich and glycine-rich protein genes were highly differentially expressed in both genetic backgrounds. Other genes that showed significant expression changes in each of the isoline pairs at the 100-200 mg seed weight stage were xylem serine proteinase, fasciclin-related genes, auxin and stress response related genes, TRANSPARENT TESTA 1 (TT1) and other transcription factors. The mutant appears to shift the timing of either the increase or decrease in the levels of some of the transcripts. The analysis of these data sets reveals the physiological changes that the seed coat undergoes during the formation of the breaks in the cell wall.
2014-05-16 | GSE54903 | GEO
Project description:Glycine max (Clark 63) genome resequencing