Root system architecture is an important trait affecting the uptake of nutrients and water by crops. Shallower root systems preferentially take up nutrients from the topsoil and help avoid ...unfavorable environments in deeper soil layers. We have found a soil-surface rooting mutant from an M^sub 2^ population that was regenerated from seed calli of a japonica rice cultivar, Nipponbare. In this study, we examined the genetic and physiological characteristics of this mutant. The primary roots of the mutant showed no gravitropic response from the seedling stage on, whereas the gravitropic response of the shoots was normal. Segregation analyses by using an F^sub 2^ population derived from a cross between the soil-surface rooting mutant and wild-type Nipponbare indicated that the trait was controlled by a single recessive gene, designated as sor1. Fine mapping by using an F^sub 2^ population derived from a cross between the mutant and an indica rice cultivar, Kasalath, revealed that sor1 was located within a 136-kb region between the simple sequence repeat markers RM16254 and 2935-6 on the terminal region of the short arm of chromosome 4, where 13 putative open reading frames (ORFs) were found. We sequenced these ORFs and detected a 33-bp deletion in one of them, Os04g0101800. Transgenic plants of the mutant transformed with the genomic fragment carrying the Os04g0101800 sequence from Nipponbare showed normal gravitropic responses and no soil-surface rooting. These results suggest that sor1, a rice mutant causing soil-surface rooting and altered root gravitropic response, is allelic to Os04g0101800, and that a 33-bp deletion in the coding region of this gene causes the mutant phenotypes.PUBLICATION ABSTRACT
Rice production faces the challenge to be enhanced by 50% by year 2030 to meet the growth of the population in rice-eating countries. Whereas yield of cereal crops tend to reach plateaus and a yield ...is likely to be deeply affected by climate instability and resource scarcity in the coming decades, building rice cultivars harboring root systems that can maintain performance by capturing water and nutrient resources unevenly distributed is a major breeding target. Taking advantage of gathering a community of rice root biologists in a Global Rice Science Partnership workshop held in Montpellier, France, we present here the recent progresses accomplished in this area and focal points where an international network of laboratories should direct their efforts.PUBLICATION ABSTRACT
IL-17-producing Th17 cells and IFN-γ and IL-17 double-producing Th1/17 cells have been identified as the pathogenic cells in inflammatory bowel disease (IBD). Retinoic acid-related orphan receptor γt ...(RORγt) is a master regulator for the differentiation and activation of Th17 and Th1/17 cells. We discovered a novel orally available TAK-828F, a strong and selective RORγt inverse agonist. To assess the potential of RORγt blockade in the therapy for IBD, the efficacy of TAK-828F in activated T cell transfer mouse colitis model was investigated. This model was highly sensitive to the prophylactic treatment of anti-TNF-α monoclonal antibody but partially susceptible to sulfasalazine, tacrolimus, and prednisolone. Oral administration of TAK-828F, at doses of 1 and 3 mg/kg, b.i.d, strongly protected the progression of colitis. TAK-828F decreased the population of Th17 and Th1/17 cells in a dose-dependent manner in the mesenteric lymph node. Moreover, expression of mRNA that are characteristic of the Th17 signature, such as IL-17A and IL-17F in the colon, were inhibited by TAK-828F, while the expression of IL-10, an anti-inflammatory cytokine, was increased. In the therapeutic treatment, TAK-828F lessened disease severity compared to the vehicle control mice. Interestingly, gene expression of zonula occludens-1 (ZO-1) and mucin 2 (Muc2), which play an important role in barrier function of the intestinal mucosa, was recovered by TAK-828F. These results indicate that blocking RORγt has promising pharmacological profile in the colitis model. RORγt blockade may provide a novel therapeutic paradigm for treatment of IBD with unique mechanism by which improves imbalance of the immune system.
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