Xanthomonas bacteria secrete transcription activator-like effector (TALE) proteins into host cells to activate plant disease susceptibility genes to cause disease, and the process is dependent on interaction between bacteria TFB domain of TALEs and host plant basal transcription factor IIA gamma subunit (TFIIAγ). The key domain or residues of plant TFIIAγ and core residues of bacteria TFB domain that are indispensable for TFIIAγ-TALEs interaction in the process of TALE-carrying Xanthomonas invasion plants are unknown. Here, we showed that the third α-helix domain of OsTFIIAγ5/Xa5, especially the 38th, 39th, 40th and 42th residues were key sites for capturing by TALEs of Xanthomonas oryzae pv. oryzae (Xoo), the causal agent of rice bacterial blight disease. The latter segment of Xoo TFB domain harboring seventy-two amino acid residues was vital for TALE specific binding with host plant OsTFIIAγ5/Xa5. Substitution of some residues in this core region of TFB domain completely compromised capacity of TALEs capturing rice OsTFIIAγ5/Xa5. The rich and conserved arginine residues in this core region of TFB domain were responsible for TALE-dependent plant susceptibility gene activation and virulence of Xoo. These results provide a potential strategy for improving resistance to TALE-carrying pathogens in plants by site-specific modification of key residues of host plant TFIIAγ. 

Machine harvesting increases the foreign matter content of seed cotton.  Excessive cleaning causes fiber damage and economic loss.  Most trading companies in the Xinjiang Uygur Autonomous Region, China have indicated reluctance to use machine-harvested cotton.  The first objective was to determine how the fiber quality was affected by the ginning and lint cleaning and how the fiber damage during levels of lint cleaning changed. The second objective was to determine the optimum number of lint cleaners for machine-harvested cotton based on fiber damage.  Cotton samples were collected from 13 fields and processed in seven ginneries between 2013 and 2015.  The results indicated that ginning and lint cleaning didn’t have significant effect on fiber strength and significantly affected both fiber length and short fiber index.  Fiber length was reduced by more than 1.00 mm from six of 13 fields after lint cleaning, then the damage rate on short fiber index from 11 of 13 fields was more than 20%.  The third lint cleaning caused great fiber damage, reducing fiber length by 0.35 mm and increasing short fiber index by 0.65%.  So, the lint should be cleaned by one lint cleaner in the Xinjiang, however, the stage of lint cleaning was sometimes omitted when the foreign matter content of lint was little.

Organophosphate insecticide residues on vegetable, fruit, tea and even grains are primary cause of food poisoning. Organophosphate compounds can cause irreversible inhibition of the activity of acetylcholinesterase and butyrylcholinesterase (BChE, EC 3.1.1.8), which are both candidates for rapid detection of organophosphate pesticides. To develop an easy-tohandle method for detecting organophosphate pesticides using BChE, BChE from human was optimized according to the codon usage bias of Pichia pastoris and successfully expressed in P. pastoris GS115. The codon-optimized cDNA shared 37.3% of the codon identity with the native one. However, the amino acid sequence was identical to that of the native human butyrylcholinesterase gene (hBChE) as published. The ratio of guanine and cytosine in four kinds of bases ((G+C) ratio) was simultaneously increased from 40 to 47%. The recombinant hBChE expression reached a total protein concentration of 292 mg mL–1 with an activity of 14.7 U mL–1, which was purified 3.2×103-fold via nickel affinity chromatography with a yield of 68% and a specific activity of 8.1 U mg–1. Recombinant hBChE was optimally active at pH 7.4 and 50°C and exhibited high activity at a wide pH range (>60% activity at pH 4.0 to 8.0). Moreover, it had a good adaptability to high temperature (>60% activity at both 50 and 60°C up to 60 min) and good stability at 70°C. The enzyme can be activated by Li+, Co+, Zn2+ and ethylene diamine tetraacetic acid (EDTA), but inhibited by Mg2+, Mn2+, Fe2+, Ag+ and Ca2+. Na+ had little effect on its activity. The values of hBChE of the Michaelis constant (Km) and maximum reaction velocity (Vm) were 89.4 mmol L–1 and 1 721 mmol min–1 mg–1, respectively. The bimolecular rate constants (Ki) of the hBChE to four pesticides were similar with that of electric eel AChE (EeAChE) and higher than that of horse BChE (HoBChE). All values of the half maximal inhibitory concentration of a substance (IC50) for hBChE were lower than those for HoBChE, but most IC50 for hBChE were lower than those for EeAChE except dichlorvos. The applicability of the hBChE was further verified by successful detection of organophosphate insecticide residues in six kinds of vegetable samples. Thus, hBChE heterologously over-expressed by P. pastoris would provide a sufficient material for development of a rapid detection method of organophosphate on spot and produce the organophosphate detection kit.

Temperature is one of the key factors that influence cotton fiber synthesis at the late growth stage of cotton. In this paper, using two early-maturing cotton varieties as experimental materials, night temperature increase was stimulated in the field using far-infrared quartz tubes set in semi-mobile incubators and compared with the normal night temperatures (control) in order to investigate the effects of night temperature on the cotton fiber cellulose synthesis during secondary wall thickening. The results showed that the activity of sucrose synthase (SuSy) and sucrose phosphate synthase (SPS) quickly increased and remained constant during the development of cotton fiber, while the activity of acid invertase (AI) and alkaline invertase (NI) decreased, increased night temperatures prompted the rapid transformation of sugar, and all the available sucrose fully converted into cellulose. With night temperature increasing treatment, an increase in SuSy activity and concentration of sucrose indicate more sucrose converted into UDPG (uridin diphosphate-glucose) during the early and late stages of cotton fiber development. Furthermore, SPS activity and the increased concentration of fructose accelerated fructose degradation and reduced the inhibition of fructose to SuSy; maintaining higher value of allocation proportion of invertase and sucrose during the early development stages of cotton fiber, which was propitious to supply a greater carbon source and energy for cellulose synthesis. Therefore, the minimum temperature in the nightime was a major factor correlated with the activity of sucrose metabolism enzymes in cotton fiber. Consequently, soluble sugar transformation and cellulose accumulation were closely associated with the minimum night temperature.

Genetic diversity of 158 accessions of an applied core collection of adzuki bean (Vigna angularis) and 18 wild genotypes were assessed by using 85 microsatellite markers. With an average of 5.81 alleles per locus, 493 alleles were detected, and their distribution frequencies lower than 5% accounted for 73.02% of the total number. The distributions of alleles between the cultivated and the wild adzuki bean germplasm are different, with a higher allelic diversity in the wild germplasm than that of the cultivated ones. An obvious genetic differentiation was also observed between the wild and the cultivated adzuki beans, and SSR markers may be useful in study identification and classification of them. Among cultivated adzuki bean, the genetic similarity coefficient varied from 0.366 to 0.939. Genetic structure analysis can clearly separate the wild genotypes from the cultivated adzuki bean, and also can divide the cultivated ones into different populations, as these populations are closely agreeable with the ecological regions where they originally grow. The results of this study will be useful in arranging local breeding programs, especially in the aspect of parental combinations or identification of progenies. These SSR markers can also provide important information to explain the genetic relationship between the cultivated and wild adzuki beans, and to accelerate the wild gene resources in broadening the gene pool in breeding program.