Quiz: Section K, L, M and N, 40 min, English answer only 1. Please list the important cis-acting elements and transacting enzymes/factors in prokaryotic transcription including initiation, elongation and termination, and briefly describe their corresponding roles (35 point)
Although DNA replication, repair, homologous recombination occur with high fidelity to ensure the genome identity between generations, there are genetic processes that rearrange DNA sequences and thus lead to a more dynamic genome structure Two classes of genetic recombination for DNA rearrangement: • Conservative site-specific recombination (CSSR): recombination between two defined sequence elements • Transpositional recombination (Transposition): recombination between specific sequences and nonspecific DNA sites
Most of the eukaryotic genes are mosaic (嵌合体), consisting of intervening sequences separating the coding sequence ◼ Exons (外显子): the coding sequences ◼ Introns (内含子) : the intervening sequences ◼ RNA splicing: the process by which introns are removed from the premRNA. ◼ Alternative splicing (可变剪接): some pre-mRNAs can be spliced in more than one way , generating alternative mRNAs. 60% of the human genes are spliced in this manner
Topic 1: THE CODE IS DEGENERATE Topic 2: THREE RULES GOVERN THE GENETIC CODE Topic 3: SUPPRESSOR MUTATIONS CAN RESIDE IN THE SAME OR A DIFFERENT GENE Topic 4: THE CODE IS NEARLY UNIVERSAL
Similarity of regulation between eukaryotes and prokaryote 1.Principles are the same: • signals (信号), • activators and repressors (激活蛋白和阻 遏蛋白) • recruitment and allostery, cooperative binding (招募，异构和协同结合) 2. The gene expression steps subjected to regulation are similar, and the initiation of transcription is the most pervasively regulated step
1. Recognizing the life of scientists. 2. Recognizing the value and nature of science. 3. Recognizing the characters displayed during the scientific activity: love of the beauty of nature, the faith of your creativity and the hope to be recognized
