遗传 ›› 2019, Vol. 41 ›› Issue (6): 548-563.doi: 10.16288/j.yczz.19-084

• 遗传学教学 • 上一篇    下一篇

乳糖操纵子模型的建立与教学中若干问题的解析

邢万金   

  1. 内蒙古大学生命科学学院,呼和浩特 010070
  • 收稿日期:2019-03-27 修回日期:2019-05-13 出版日期:2019-06-20 发布日期:2019-05-27
  • 作者简介:邢万金,博士,教授,研究方向:细胞分子生物学。E-mail:xwanjin@imu.edu.cn
  • 基金资助:
    遗传学课程群教学团队建设项目,内蒙古大学精品资源共享课程建设项目,混合式教学课程建设项目和研究生精品课程建设项目资助

The establishment process of lac operon model and the analysis of several teaching problems

Wanjin Xing   

  1. School of Life Sciences, Inner Mongolia University, Hohhot 010070, China
  • Received:2019-03-27 Revised:2019-05-13 Online:2019-06-20 Published:2019-05-27
  • Supported by:
    Supported by the Teaching Team Construction Project of Genetics Course Group and the Curriculum Construction Projects of Inner Mongolia University

摘要:

基因结构和表达调控机制是现代生命科学的研究热点和焦点。乳糖操纵子是大肠杆菌(Escherichia coli)分解代谢乳糖的一簇基因,其基因组成与表达调控方式是最早被阐明的基因结构与调控机制,因而成为微生物学、遗传学和分子生物学等多门专业课程讲解基因调控机制的经典教学案例和要求重点掌握的内容,备受师生们的重视。该知识点虽然结论简单,记忆容易,但由于触及生命结构与功能的核心机制,内涵丰富,逻辑深奥,理解困难。教师要充分发挥该教学案例的效果并非易事,需要深入了解乳糖操纵子的基因结构和工作原理,特别是科学家揭秘这些奥秘的科学背景和思维过程。本文通过回溯大肠杆菌乳糖操纵子发现和表达模式解析的历程,追随J. Monod和F. Jacob等前辈名家的脚印,聆听他们对实验结果的分析,学习他们的科研思想和创新思维,结合乳糖操纵子的DNA序列,深入分析和理解乳糖操纵子表达的若干奇特现象的原因,共同探讨如何充分发挥遗传学和分子生物学经典案例的教学价值。

关键词: 遗传学, 案例教学, 乳糖操纵子, 基因调控

Abstract:

Gene structure and expression regulation mechanism are the research hotspots and focus of modern life sciences. The lac operon is a cluster of genes through which Escherichia coli catabolizes lactose. It was first proposed by F. Jacob and J. Monod, who were also awarded the Nobel Prize in Physiology or Medicine in 1965 for their contributions. Thereafter, the lac operon has become the classic teaching case of the gene regulation mechanism in microbiology, genetics and molecular biology, and been highly valued by teachers and students alike. Although the conclusion is easy to follow and memorize, its rich connotation and esoteric reasoning has rendered it difficult to understand, neither is it easy for teachers to fully exploit the advantages of this teaching case. Therefore it is necessary to have an in-depth understanding of the genetic structure and working principle of the lac operon, especially the scientific background and thinking process through which scientists revealed these mysteries. In this paper, the historical discovery and analysis process of the E. coli lac operon was reviewed by following their footprints, listening to their analysis of experimental results. Based on the DNA sequences, the reasons for several unusual phenomena of lac operon expression were also discussed to exemplify the teaching value of the classic cases in genetics and molecular biology.

Key words: genetics, case teaching, lac operon, gene regulation