Application of modern computer technology in classical genetics lab course--Development of a mobile, lightweight and high-precision batch identification system for genetic traits of Drosophila.

Drosophila is a crucial biological experimental teaching material extensively utilized in experimental teaching. In this experimental teaching, each student typically needs to manually identify hundreds of fruit flies and record multiple of each fly. This task involves substantial workload, and the classification standards can be inconsistent. To address this issue, we introduce a deep convolutional neural network that classifies the traits of every fruit fly, using a two-stage consisting of an object detector and a trait classifier. We propose a keypoint-assisted classification model with tailored training session for the trait classification task and significantly enhanced the model interpretability. Additionally, we've enhanced the RandAugment method to better fit the features of our task. The model is trained with progressive learning and adaptive regularization under limited computational resources. The final classification model, which utilizes MobileNetV3 as backbone, achieves an accuracy of 97.5%, 97.5% and 98% for the eyes, wings, gender tasks, respectively. After optimization, the model is highly lightweight, classifying 600 fruit fly traits from raw images in 10 seconds and having a size less than 5 MB. It can be easily deployed on any android device. The development of this system is conducive to promoting the experimental teaching, such as verifying genetic laws with Drosophila as the research object. It can also be used for scientific research involving a large number of Drosophila classifications, statistics and analyses.

[Curriculum design and practice of Genetics blended course under the principle of constructive alignment].

Genetics is a branch of biology that studies the laws of inheritance and variation from the level of genes (genomes). Genetics teaching should be compatible with the evolving genetic disciplines and social needs. In view of the continuous development of the genetics knowledge system and the requirements for the training of biological students, our teaching team carried out the curriculum design and implementation of genetics blended course under the principle of constructive alignment. The reform actions include: (1) constructing genetics online resources with genetic analysis as the main line; (2) optimizing the learning objectives according to bloom's educational goals classification; (3) designing learning activities and learning assessments under the principle of constructive alignment; (4) enrich the forms of learning activities, highlighting learning-centered course design and learner interaction, promoting active learning, and improving learning outcomes. The results of the questionnaire survey and exam result analysis suggest that the blended course reform has achieved initial results. The course is fully affirmed by the students and helps to improve learning outcomes, which is worthy of further consolidation and promotion. This paper generally introduces the curriculum design and preliminary practice of genetics blended course, providing new insights and approaches for the continued development of genetics teaching in the new era.

Simplification of genotyping techniques of the ABO blood type experiment and exploration of population genetics.

The ABO blood type is one of the most common and widely used genetic traits in humans. Three glycosyltransferase-encoding gene alleles, IA, IB and i, produce three red blood cell surface antigens, by which the ABO blood type is classified. By using the ABO blood type experiment as an ideal case for genetics teaching, we can easily introduce to the students several genetic concepts, including multiple alleles, gene interaction, single nucleotide polymorphism (SNP) and gene evolution. Herein we have innovated and integrated our ABO blood type genetics experiments. First, in the section of Molecular Genetics, a new method of ABO blood genotyping was established: specific primers based on SNP sites were designed to distinguish three alleles through quantitative real-time PCR. Next, the experimental teaching method of Gene Evolution was innovated in the Population Genetics section: a gene-evolution software was developed to simulate the evolutionary tendency of the ABO genotype encoding alleles under diverse conditions. Our reform aims to extend the contents of genetics experiments, to provide additional teaching approaches, and to improve the learning efficiency of our students eventually.

[Exploration on human blood type case in teaching practice of genetics].

Blood type, which harbors abundant genetics meaning, is one of the most common phenotypes in human life. With the development of science and technology, its significance is unceasingly updated and new finding is increasingly emerging, which constantly attracts people to decipher the heredity mechanism of blood type. In addition to four main associated contents, i.e., Mendelian inheritance, genetic linkage, gene mutations, and chromosome abnormalities, the blood type case also covers many other aspects of the genetics knowledge. Based on the genetic knowledge context, we can interest the students and improve the teaching output in genetic teaching practice by combining with explaining ABO blood type case and heredity mechanism, expanding leucocyte groups, and introducing infrequent blood type such as Bombay blood, Rh and MN. By carrying out the related experimental teaching, we could drive the student to integrate theory with practice. In genetic experimental teaching, 80% of the students chose this optional experiment, molecular identification of ABO blood type, and it greatly interested them. Using appropriate blood type case in teaching related knowledge, organizing PPT exhi-bition and the debating discussion activities, it could provide opportunities for student to propose their own opinions, guide the student to thinking deeply, and develop their abilities to analyze and solve problem. Afterwards, students will gain in-depth comprehension about the fundamental knowledge of genetics.

[From gene cloning to expressional analysis--practice and experience from educational reform of experimental gene engineering].

Experimental gene engineering is a laboratory course focusing on the molecular structure, expression pattern and biological function of genes. Providing our students with a solid knowledge base and correct ways to conduct research is very important for high-quality education of genetic engineering. Inspired by recent progresses in this field, we improved the experimental gene engineering course by adding more updated knowledge and technologies and emphasizing on the combination of teaching and research, with the aim of offering our students a good start in their scientific careers.

[Development research of the genetics textbook in Chinese universities].

Textbook construction is an important part of course construction. The development of the Chinese genetics teaching has been full of ups and downs, demonstrating its specificity compared with other subjects of life science. Through the investigation upon the developmental course of genetics textbooks in China from before liberation to the 21st century, we hope that we can provide valuable reference for composing new textbooks that fit the characteristic of undergraduates teaching, and keep close to the genetics front, bringing valuable reference to the cultivation of application and study talents with basic genetics knowledge and innovation ability.

Blocking of N-acetylglucosaminyltransferase V induces cellular endoplasmic reticulum stress in human hepatocarcinoma 7,721 cells.

N-acetylglucosaminyltransferase V (GnT-V) is an important tumorigenesis and metastasis-associated enzyme. To study its biofunction, the GnT-V stably suppressed cell line (GnT-V-AS/7,721) was constructed from 7,721 hepatocarcinoma cells in previous study. In this study, cDNA array gene expression profiles were compared between GnT-V-AS/7,721 and parental 7,721 cells. The data indicated that GnT-V-AS/7,721 showed a characteristic expression pattern consistent with the ER stress. The molecular mechanism of the ER stress was explored in GnT-V-AS/7,721 by the analysis on key molecules in both two unfolded protein response (UPR) pathways. For ATF6 and Ire1/XBP-1 pathway, it was evidenced by the up-regulation of BIP at mRNA and protein level, and the appearance of the spliced form of XBP-1. As for PERK/eIF2alpha pathway, the activation of ER eIF2alpha kinase PERK was observed. To confirm the results from GnT-V-AS/7,721 cells, the key molecules in the UPR were examined again in 7,721 cells interfered with the GnT-V by the specific RNAi treatment. The results were similar with those from GnT-V-AS/7721, indicating that blocking of GnT-V can specifically activate ER stress in 7,721 cells. Rate of (3)H-Man incorporation corrected with rate of (3)H-Leu incorporation in GnT-V-AS/7,721 was down-regulated greatly compared with the control, which demonstrated the deficient function of the enzyme synthesizing N-glycans after GnT-V blocking. Moreover, the faster migrating form of chaperone GRP94 associated with the underglycosylation, and the extensively changed N-glycans structures of intracellular glycoproteins were also detected in GnT-V-AS/7,721. These results supported the mechanism that blocking of GnT-V expression impaired functions of chaperones and N-glycan-synthesizing enzymes, which caused UPR in vivo.

A novel strategy to compensate the disadvantages of live vaccine using suicide-gene system and provide better antitumor immunity.

Fusing dendritic cells (DCs) with tumor cells is a powerful vaccine to increase tumor immunogenicity. To develop more effective and safer therapeutic vaccine, we fused rat bone marrow-derived DCs with ovarian tumor cell line NuTu-19 modified by suicide gene (HSV1-TK gene) to obtain live vaccine against ovarian cancer. Our data showed that immunization of rats with such live vaccine solicited stronger ovarian tumor-specific cytotoxic T lymphocyte responses and induced immunopreventive and immunotherapeutic effects against parental tumor cells in vivo. Live vaccine could be induced to death after ganciclovir administration in vitro and in vivo. Our researches suggest that live vaccine modified with suicide gene might be effective and controllable in the therapy of ovarian cancer.

The construction, characterization and transfection of liposome- polycation-CDKN1B plasmid complexes.

OBJECTIVE: To develop an efficient non-viral gene delivery system in order to transfer CDKN1B gene efficiently into lung and liver carcinoma cells. METHODS: A recombinant plasmid composed of CDKN1B sequence and EYFP as reporter gene was constructed and identified. The recombinant DNA was then formulated the lipids-polycation-DNA complexes(LPDs) with protamine sulfate. Several kinds of lung and liver carcinoma cells were transfected by means of LPDs. The physicochemical properties of LPDs were investigated using PCS method and TEM, respectively. The expression of EYFP in A549 cells was observed under fluorescent microscope and evaluated by flow cytometry analysis. Finally, the production of CDKN1B protein in transfected LLC, Chang and 7721 cells was identified by Western blot analysis. RESULTS: The average diameter of the LPDs were 167 nm with the polydispersity index of 0.35. The average zeta potential of LPDs was +32.6 mV. LPDs look like a sunken sphere. The fluoresent microscope picture clearly indicated the expression of EYFP in A549 cells. The flow cytometry result showed that the transfection efficiency of LPDs in A549 cells was comparable with that of LipofectAMINE, the positive control. Western blot analysis confirmed the production of CDKN1B protein in LLC, Chang and 7721 cells transfected with LPDs, while no CDKN1B protein was detected in cells transfected with naked DNA. CONCLUSION: The construction of the recombinant plasmid is successful. LPDs can deliver the recombinant plasmid to lung carcinoma cells and liver carcinoma cells with high efficiency. Therefore, this kind of gene delivery system has the potential uses for the treatment of lung and liver cancer.