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Color development in various rice organs results from the complementary expression of genes involved in anthocyanin biosynthesis. The Purple pericarp (Prp) trait and the Purple leaf (Pl) trait both display epistasis, relying on the complement of the Pb and Pp genes for pericarp coloration and the Pl and Pp genes for leaf coloration, respectively. However, there is still genetic uncertainty in identifying the genes responsible for the various color expressions and intensities of rice grain pericarp and leaves. In this study, we characterized the inheritance patterns of color development and the mode of anthocyanin pigments in rice by crossing two parental mutant lines. YUM051, exhibiting dark purple leaves (Plw) and purple pericarp (Prp), was crossed with YUM144, which displayed light purple leaves (Pli) and a white pericarp (prp). The F1 plants exhibited dark purple leaves with purple pericarps, indicating the dominant nature of the purple leaf (Pl) and purple pericarp (Prp) traits. The rice Prp traits display a complementary interaction, reflected in a 9:7 ratio of purple to white pericarp. However, the Prp trait followed Mendelian segregation with a 3:1 ratio of purple to white pericarp in this cross, indicating homozygous dominant Pp alleles in both parental plants. Meanwhile, the segregation of the purple leaf color in the F2 generation of this cross followed complementary inheritance, exhibiting a 9:7 segregation ratio between purple leaves and greenish leaves with purple leaf margins. Moreover, the co-segregation of Prp and Pl traits in the cross between YUM051 (Plw) and YUM144 (Pli) plants did not adhere to the Mendelian 9:3:3:1 independent assortment ratio, confirming that the Pl gene and Pb gene are linked on the same chromosome. Cyanidin-3-O-glucoside (C3G) was detected in the leaves of all progeny resulting from the Plw and Pli cross. However, C3G was exclusively identified in the seeds of offspring carrying the dominant Pb gene. Therefore, the Plw and Pli alleles are Pl genes responsible for purple leaf color, while the Pb gene is responsible for purple pericarp color in rice; these genes function independently of each other. [ABSTRACT FROM AUTHOR]

The biological activities of Houttuynia cordata (H. cordata) fermented with Aureobasidium pullulans (A. pullulans) was investigated for human skin keratinocyte-induced chemical and photo oxidations. In this research, H2O2/UVA-induced HaCaT cell lines were treated with H. cordata water/ethanol extracts (HCW/HCE) and fermented with A. pullulans water/ethanol extracts (HCFW/HCFE). A. pullulans fermented with H. cordata (HCFW) increased in 5.4-folds of total polyphenol (HCFW 46.89 mg GAE/extract g), and 2.3-folds in flavonoids (HCFW 53.80 mg GAE/extract g) compared with water extracts of H. cordata (HCW). Further, no significant cytotoxicity for HaCaT cells showed by all the extracts of H. cordata fermented with A. pullulans. HCFW extracts have significantly lowered inflammation factors such as COX-2 and Hsp70 proteins in oxidative stressed HaCaT cells induced by H2O2 and UVA treatments. All H. cordata extracts significantly downregulated gene expression involved in oxidative stress and inflammation factors, including IL-1β, IL-6, COX-2, TNF-α, NF-κB, and MMP-1 in the H2O2/UVA-treated HaCaT cells. However, keratin-1 gene expression in the UVA-treated HaCaT cells was increased in twofolds by HCFW extracts. Further, A. pullulans fermented H. cordata extracts (HCFW/HCFE) reduced the genes involved in oxidative stresses more effectively than those of H. cordata extract only. Overall, the polyphenol-rich extracts of H. cordata fermented with A. pullulans showed synergistic protective effects for human epidermal keratinocytes to prevent photoaging and intrinsic aging by anti-oxidation and anti-inflammatory functions. [ABSTRACT FROM AUTHOR]

Using the fluorescence in situ hybridization (FISH) technique, we conducted karyotype analyses to identify the lost chromosomes in three somaclonal variants obtained from tissue culture of wild Allium tuberosum (2n = 4X = 32). The three lost chromosomes of the At29 variant (2n = 29) were all chromosome 2, the two for At30 (2n = 30) were chromosomes 7 and 8, and At31 was missing chromosome 2. Chromosome compositions of these variants were confirmed as being fixed lines during two years of greenhouse cultivation. The bicolor FISH technique, involving both 5S and 18S–5.8S–26S ribosomal RNA genes as probes, was used to assign chromosomal locations and to confirm whether the lost chromosomes contained any rRNA markers. The 5S rRNA gene signals in all variants as well as the wild type were detected as two sets, one on the intercalary region of the short arm of chromosome 3, the other on the intercalary region of the long arm of chromosome 6. One 18S–5.8S–26S rRNA gene site on the secondary constriction included a flanking satellite and terminal region on the short arm of chromosome 8. Signals of the 18S–5.8S–26S rRNA gene in At30 showpd in only three chromosomes, indicating that one of the lost chromosomes was chromosome 8. Overall, three marker chromosomes were established by FISH, using rRNA multigene families. [ABSTRACT FROM AUTHOR]

The failure of midrib formation in rice leaf blades results in the drooping leaf (dl) phenotype. A normal DROOPING LEAF (DL) gene is necessary for leaf homeotic transformation, which affects midrib and pistil development. Genetic analysis was performed on a new drooping leaf (dl) mutant named dl - 6 in rice. The dl-6 allelic mutant exhibited drooping leaves that were severely folded and twisted at the base but had normal flower structure. The dl-6 allele is a nuclear recessive trait that fits a 3:1 Mendelian segregation ratio. The dl-6 mutant leaves displayed an abnormal main vein (midrib-less) with undeveloped aerenchyma and vascular bundles, resulting in severe leaf drooping. The lack of a midrib in dl-6 caused weak mechanical support, which resulted in folding at the collar junction of the leaf base and downward bending. Through genetic mapping, the dl-6 allele was identified at approximately 28.2 cM on rice chromosome 3. The allele was caused by mutations within the DL (LOC_Os03g11600.1) gene, with specific amino acid substitutions and additions in the encoded protein of the YABBY transcription factor. The dl-6 mutant is a recessive allele encoding a dysfunctional YABBY transcription factor that regulates leaf midrib development and aerenchymatous clear cell structures, leading to a drooping leaf phenotype in rice. [Display omitted] • Rice dl-6 mutant allele is associated with drooping leaf and twisted and folded leaf base. • The dl-6 mutant is caused by deficiency in leaf midrib development. • The dl-6 allele is a nuclear recessive gene for YABBY transcription factor in rice chromosome 3. [ABSTRACT FROM AUTHOR]