Effect of Two Herbicides on the Growth of Early Seedlings of Rye(Secale cereale)

[Objective]The aim was to study the effect of herbicide on the growth of early seedlings of rye（Secale cereale）.[Method]Effect of two kinds of herbicide（Atrazine and APM）on seedling growth of rye was investigated at the physiological,biochemical and cellular level.[Result]The Atrazin significantly decreased the contents of chlorophyll a,b and soluble proteins.Rye seeds were treated with 0.01-1 mg/L Atrazine for 16 h,the contents of chlorophyll a and b decreased from 1.26（a）,0.49（b）mg/g FW（control）to 1.15（a）,0.46（b）mg/g FW（0.1 mg/L）and 0.81（a）,0.33（b）mg/g FW（1.0 mg/L）.The content of soluble protein decreased with the increasing concentration of Atrazin.Atrazin had no significant influence on the cell division and chromosome structure variation.The contents of chlorophyll a,b and soluble proteins had no significantly change under the treatment of APM,but the number of chromosome structure variation such as chromosome bridge,multipolar division cells,lagging chromosome and unequal division cells increased significantly.[Conclusion]The critical concentration of Atrazine was 0.1-1.0 mg/L and 4 mg/L of APM in rye.

Chromatin-binding in vivo of the erythroid kruppel-like factor,EKLF,in the murine globin loci

EKLF is an erythroid-specific, zinc finger-containing transcription factor essential for the activation of the mammalian beta globin gene in erythroid cells of definitive lineage. We have prepared a polyclonal anti-mouse EKLF antibody suitable for Western blotting and immunoprecipitation （IP） qualities, and used it to define the expression patterns of the EKLF protein during mouse erythroid development. We have also used this antibody for the chromatin-immunoprecipitation （CHIP） assay. EKLF was found to bind in vivo at both the mouse beta-major-globin promoter and the HS2 site of beta-LCR in the mouse erythroleukemia cells （MEL） in a DMSO-inducible manner. The DMSO-induced bindings of EKLF as well as three other proteins, namely, RNA polymerase Ⅱ, acetylated histone H3, and methylated histone H3, were not abolished but significantly lowered in CB3, a MEL-derived cell line with null-expression of p45/NF-E2, an erythroid-enriched factor needed for activation of the mammalian globin loci. Interestingly, binding of EKLF in vivo was also detected in the mouse alpha-like globin locus, at the adult alpha globin promoter and its far upstream regulatory element alpha-MRE （HS26）. This study provides direct evidence for EKLF-binding in vivo at the major regulatory elements of the mouse beta-like globin gene clusters the data also have interesting implications with respect to the role of EKLF-chromatin interaction in mammalian globin gene regulation.

ANEUPLOIDY INDUCTION BY THE WATER EXTRACT OF TRIPTERYGIUM HYPOGLAUCUM(LEVEL) HUTCH IN MOUSE BONE MARROW CELLS

The aneuploldy inducing activity of a Chinese medicinal herb, Tripterygium hypoglaucum (level) Hutch (THH) were investigated by means of thhree cytogenetic end points, namely C-mitotic (CM) effects, micronucleus (MN) and parallel chromosome structural aberration (CA) analyses in vivo. The experiments were performed on mouse bone marrow cells. THH showed similar gentoxic effects to colchicine (COL) in CM, MN and CA analyses; positive CM effects were observed accompanied with increases of mitotic index and frequencies of C-mltotic cells as well as decreased frequencies of anaphase in all of the THH-treated groups. The compound showed a positive MN response in bone marrow polychromatic erythrocytes but was negative in CA analyses. The preliminary results suggested that THH is an aneuploldy inducer in mouse bone marrow cells under present experiment conditions.

Knowledge-embedded spatio-temporal analysis for euploidy embryos identification in couples with chromosomal rearrangements

Background:The goal of the assisted reproductive treatment is to transfer one euploid blastocyst and to help infertile women giving birth one healthy neonate.Some algorithms have been used to assess the ploidy status of embryos derived from couples with normal chromosome,who subjected to preimplantation genetic testing for aneuploidy(PGT-A)treatment.However,it is currently unknown whether artificial intelligence model can be used to assess the euploidy status of blastocyst derived from populations with chromosomal rearrangement.Methods:From February 2020 to May 2021,we collected the whole raw time-lapse videos at multiple focal planes from in vitro cultured embryos,the clinical information of couples,and the comprehensive chromosome screening results of those blastocysts that had received PGT treatment.Initially,we developed a novel deep learning model called the Attentive Multi-Focus Selection Network(AMSNet)to analyze time-lapse videos in real time and predict blastocyst formation.Building upon AMSNet,we integrated additional clinically predictive variables and created a second deep learning model,the Attentive Multi-Focus Video and Clinical Information Fusion Network(AMCFNet),to assess the euploidy status of embryos.The efficacy of the AMCFNet was further tested in embryos with parental chromosomal rearrangements.The receiver operating characteristic curve(ROC)was used to evaluate the superiority of the model.Results:A total of 4112 embryos with complete time-lapse videos were enrolled for the blastocyst formation prediction task,and 1422 qualified blastocysts received PGT-A(n=589)or PGT for chromosomal structural rearrangement(PGT-SR,n=833)were enrolled for the euploidy assessment task in this study.The AMSNet model using seven focal raw time-lapse videos has the best real-time accuracy.The real-time accuracy for AMSNet to predict blastocyst formation reached above 70%on the day 2 of embryo culture,and then increased to 80%on the day 4 of embryo culture.Combing with 4 clinical features of couples,the AUC of AMCFNet with 7 focal points increased to 0.729 in blastocysts derived from couples with chromosomal rearrangement.Conclusion:Integrating seven focal raw time-lapse images of embryos and parental clinical information,AMCFNet model have the capability of assessing euploidy status in blastocysts derived from couples with chromosomal rearrangement.

Current Status and Recent Advances in Preimplantation Genetic Testing for Structural Rearrangements

Preimplantation genetic testing(PGT)is an early form of prenatal genetic diagnosis,which can identify the abnormal embryos cultured in vitro,allow only transfer of genetically normal embryos,and improve the pregnancy rate.In recent years,the rapid development of microarrays and next-generation sequencing(NGS)technologies has remarkably accelerated the clinical application of PGT.In particular,a variety of detection methods have emerged and achieved significant progress in PGT for structural rearrangements(PGT-SR).The detection-related abilities of these methods range from the detection of limited chromosome aneuploidy to comprehensive chromosome screening of the whole genome to differentiation of embryos with normal or balanced translocation/inversion karyotypes.In this study,we reviewed PGT-SR-related detection techniques to provide a better reference for clinical application and research.We have also discussed the potential development of novel techniques in the future.