Genome editing reveals dmrt1 as an essential male sex-determining gene in Chinese tongue sole (Cynoglossus semilaevis)

Chinese tongue sole is a marine fish with ZW sex determination. Genome sequencing suggested that the Z-linked dmrt1 is a putative male determination gene, but direct genetic evidence is still lacking. Here we show that TALEN of dmrt1 efficiently induced mutations of this gene. The ZZ dmrt1 mutant fish developed ovary-like testis, and the spermatogenesis was disrupted. The female-related genes foxl2 and cyp19a1a were significantly increased in the gonad of the ZZ dmrt1 mutant. Conversely, the male-related genes Sox9a and Amh were significantly decreased. The dmrt1 deficient ZZ fish grew much faster than ZZ male control. Notably, we obtained an intersex ZW fish with a testis on one side and an ovary on the other side. This fish was chimeric for a dmrt1 mutation in the ovary, and wild-type dmrt1 in the testis. Our data provide the first functional evidence that dmrt1 is a male determining gene in tongue sole

Synthesis of Isotopically Labeled 13C3-Simazine and Development of a Simultaneous UPLC-MS/MS Method for the Analysis of Simazine in Soil

The isotope dilution mass spectrometry (IDMS) is a highly efficient method for tackling the ion suppression in complex matrix by ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS), but a lack of commercial internal standards is a limiting factor for these analyses. Herein, an economical and efficient strategy for the synthesis of 13C3-simazine via a three-step procedure was developed. The isotope-labeled internal standard was used for determination of simazine residue in soil samples. The quantitation method has a limit of detection of 0.015 μg/kg and quantitation of 0.08 μg/kg. The inter-day and intra-day precision of the method were below 4.6%. Recovery values were ranged between 92.9% and 99.2%. All the samples obtained from six provinces in China contained from 1 to 62 μg/kg of simazine

Biphasic fractionation of rice straw under mild condition in acidified 2-phenoxyethanol/water system

A novel biphasic organic solvent, 2-phenoxyethanol (EPH) was introduced to pretreat and fractionate rice straw into glucose/glucan, xylose/xylan and lignin under mild conditions. In addition, the combined severity factor (CSF) was used to evaluate the effect of pretreatment severity on the composition variation of rice straw. Under the biphasic system (0.05 M H2SO4, 70 % EPH:30 % H2O), 130 degrees C cooking rice straw 2 h, 86.48 % of cellulose retention in solid residue, 92.10 % of hemicellulose removal and 63.16 % of lignin removal were obtained. Then, the solid residue was enzymatically digested with a glucose yield of 80.94 % at 36 h, and the pure lignin (92.60 %) was recovered by simple precipitation. Based on the fractionation process, 96.69 % of glucose and glucan, 81.83 % of xylose and xylan, and 71.71 % of lignin in solid and liquid phase were recovered. Finally, the residue, especially the retrieved lignin was characterized by SEM, XRD, FTIR, HSQC and thermogravimetric analysis