Kernel weight and morphology are important traits affecting cereal yields and quality. Dissecting the genetic basis of thousand kernel weight (TKW) and its related traits is an effective method to improve wheat yield. In this study, we performed quantitative trait loci (QTL) analysis using recombinant inbred lines derived from the cross ‘PuBing3228 × Gao8901’ (PG-RIL) to dissect the genetic basis of kernel traits. A total of 17 stable QTLs related to kernel traits were identified, notably, two stable QTLs QTkw.cas-1A.2 and QTkw.cas-4A explained the largest portion of the phenotypic variance for TKW and kernel length (KL), and the other two stable QTLs QTkw.cas-6A.1 and QTkw.cas-7D.2 contributed more effects on kernel width (KW). Conditional QTL analysis revealed that the stable QTLs for TKW were mainly affected by KW. The QTLs QTkw.cas-7D.2 and QKw.cas-7D.1 associated with TKW and KW were delimited to the physical interval of approximately 3.82 Mb harboring 47 candidate genes. Among them, the candidate gene TaFT-D1 had a 1 bp insertions/deletion (InDel) within the third exon, which might be the reason for diversity in TKW and KW between the two parents. A Kompetitive Allele-Specific PCR (KASP) marker of TaFT-D1 allele was developed and verified by PG-RIL and a natural population consisted of 141 cultivar/lines. It was found that the favorable TaFT-D1 (G)-allele has been positively selected during Chinese wheat breeding. Thus, these results can be used for further positional cloning and marker-assisted selection in wheat breeding programs. Seventeen stable QTLs related to kernel traits were identified. The stable QTLs for thousand kernel weight were mainly affected by kernel width. TaFT-D1 could be the candidate gene for QTLs QTkw.cas-7D.2 and QKw.cas-7D.1. 相似文献
α-Amyrin is a plant-originated high-valued triterpene that is highly effective against several pathological ailments. α-Amyrin production by engineered Saccharomyces cerevisiae has been achieved by introducing α-amyrin synthase (αAS). However, the low yield of α-amyrin highly limits its industrial application; the low catalytic activity of αAS and the toxic effect of α-amyrin have been considered key elements. In this study, the highest yield of α-amyrin was obtained in engineered S. cerevisiae by remodeling α-amyrin synthase MdOSC1 and expanding the storage pool. The yield of α-amyrin was increased to 11-fold higher than that of the control by the triple mutant MdOSC1N11T/P250H/P373A obtained based on the modeling analysis. Furthermore, key genes of MVA pathway were overexpressed to provide sufficient precursors, and DGA1 (Diacylglycerol acyltransferase) was overexpressed to expand the intracellular storage capacity. Finally, the as-constructed aAM12 strain produced 213.7 ± 12.4 mg/L α-amyrin in the shake flask and 1107.9 ± 76.8 mg/L in fed-batch fermentation; the fermentation yield was 106-fold higher than that of the original aAM1 strain under the same conditions, representing the highest α-amyrin yield in yeast reported to date. Microbial production of α-amyrin with over 1 g/L will be suitable for commercialization and can accelerate the industrial production of α-amyrin in yeast. 相似文献
This study was to evaluate the effect of Streptococcus salivarius K12 on tongue coating–associated halitosis. Twenty-eight subjects having tongue coating–associated halitosis were randomly divided into either a test or control group. For each of the 30 days, the test subjects sucked S. salivarius K12 tablet while the control subjects sucked placebo tablets. All the subjects did not take physical (tongue scraping) and chemical (antiseptic mouth-rinse) oral cavity pretreatment prior to use of the tablets. At baseline, and on the 1st, 7th, and 14th day after completing the course of tablets, the subjects were assessed for their organoleptic test (OLT) scores, volatile sulfur compound (VSC) levels, and tongue coating scores (TCS). During the course, all subjects kept their routine oral care habits without scraping their tongue coating. Plaque index, probing depth, and bleeding index were recorded at baseline and at the completion of the trial. On the 1st day following the end of tablet use, the OLT scores and VSC levels had significantly decreased in the test group when compared with the baseline values (P = 0.001 and P = 0.012). The TCS in the test group were also significantly decreased (P = 0.05). At days 7 and 14, the OLT scores in the test group were still significantly lower than the baseline levels (P = 0.006 and P = 0.039 respectively). However, there were no statistical differences with OLT, VSC, and TCS between the test group and the placebo group by analysis of multi-level regression model. The use of S. salivarius K12 did not have significant effect on halitosis with tongue coating cause when the tongue coating was not physically or chemically pre-treated, which implies removing tongue coating is required before Streptococcus salivarius K12 use.
Reviews in Fish Biology and Fisheries - The intestinal mucosal barrier plays a critical role in the maintenance of host health. In farmed teleost fish, the intestinal epithelium is challenged by a... 相似文献