Q1. Prokaryotic cell E. coli consists of a single closed-circular DNA molecule of 4.6 x 106 bp long. This DNA molecule would be 1.6 mm if the double helix is relaxed. Please describe what strategies does E. coli use to pack such a long molecules into its nucleoid less than a micrometer (mm) in diameter. (20 points)
Q1: Please name the following amino acids (three letter name, for example: Ala for alanine). Q2: Which of them are hydrophobic AA, and which are hydrophilic?
1. What are the gene expression stages that can be regulated? (10 points) Regulated stages in gene expression: (1) transcription initiation (the most important stage): RNAP binding of the promoter, transition from the closed complex to the open complex; promoter escape 4’ (2) stages after initiation (elongation and termination) 2’ (3) RNA processing (alternative splicing) in eukaryotes 2’ (4) translation 2’
1. Please describe the main features of the DNA structure. (10 points) Key features: (1) Double helical structure (4’) (2) Two strands are held together in an antiparallel orientation (3’) by base paring (1’)
PART I: DESCRIPTION (2 points each) Your answer should describe what each item is and how it functions in the cell. Diagrams, structure and sequence information should be included in your answer, as necessary
