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A novel polysaccharide Fraction K-2-F containning 3-O-methylgalactose, which was isolated from the 70% aqueous ethanol extract of the fruiting body of Phellinus robustus Karst., was found to be homogeneous as judged by gel filtration on Sepharose CL-4B, and its molecular weight was estimated to be ca. 470,000. Another low-molecular polysaccharide fraction (K-2-L) obtained from the same extract was composed of a large amount of glucose (ca. 83%) in addition to mannose, 3-O-methylgalactose, and galactose. K-2-L showed a characteristic absorption band at 890 cm^ in the infrared spectrum, suggesting the presence of β-glycosidic linkages. In biological screening tests, K-2-F and K-2-L exhibited mitogenic activity in a dose-dependent manner, and the mitogenic potency of K-2-F was stronger than that of K-2-L. In addition, only K-2-F showed significant colony-stimulating factor-inducing activity

SlIAA9 Controls Tomato Elongation

Tomato INDOLE-3-ACETIC ACID9 (SlIAA9) is a transcriptional repressor in auxin signal transduction, and SlIAA9 knockout tomato plants develop parthenocarpic fruits without fertilization. We generated sliaa9 mutants with parthenocarpy in several commercial tomato cultivars (Moneymaker, Rio Grande, and Ailsa Craig) using CRISPR-Cas9, and null-segregant lines in the T1 generation were isolated by self-pollination, which was confirmed by PCR and Southern blot analysis. We then estimated shoot growth phenotypes of the mutant plants under different light (low and normal) conditions. The shoot length of sliaa9 plants in Moneymaker and Rio Grande was smaller than those of wild-type cultivars in low light conditions, whereas there was not clear difference between the mutant of Ailsa Craig and the wild-type under both light conditions. Furthermore, young seedlings in Rio Grande exhibited shade avoidance response in hypocotyl growth, in which the hypocotyl lengths were increased in low light conditions, and sliaa9 mutant seedlings of Ailsa Craig exhibited enhanced responses in this phenotype. Fruit production and growth rates were similar among the sliaa9 mutant tomato cultivars. These results suggest that control mechanisms involved in the interaction of AUX/IAA9 and lights condition in elongation growth differ among commercial tomato cultivars