After isolation of DNA from the source it is digested enzymatically with the help of restriction endonucleases. Enzyme treated DNA is then separated by size in an agarose gel and shifted to a membrane. A radioactive or fluorescently labeled probe is bonded with the DNA on the membrane. They target specific sequences that are marked by the restriction enzyme sites. The size of these fragments varies hence generate a biological bar code of restriction enzyme- digested DNA fragments.
The components required for prokaryotic elongation process includes ,the initiation complex described above, aminoacyl-tRNAs, a set of three soluble cytosolic elongation factors (EF-Tu, EF-Ts, and EF-G in bacteria), and GTP. During the first step of elongation cycle the next aminoacyl-tRNA binds to the ribosomal A site. The appropriate aminoacyl-tRNA associates with a complex of GTP-bound EF-Tu resulting in formation of aminoacyltRNA–EF-Tu–GTP complex. It binds to the ribosomal A site with simultaneous hydrolyzed of GTP and an EF-Tu–GDP complex is released from the 70S ribosome. The EF-Tu–GTP complex is then regenerated in a process requiring EF-Ts and GTP.
DNA also can directly repaired damaged bases. A repair enzyme recognizes incorrect structure in the DNA and directly converts it to a correct structure. Base exision repair involves a category of enzymes known as DNA-N-glycosylacases. The enzymes identify the damaged base and cleave the bond between it and the sugar in the DNA. Then it will remove one base, excises several around it and then replaces it with several new bases using DNA polymerase adding to 3’ ends and then closing it with ligase attached to 5’ end.
Student’s Name Professor’s Name Subject DD Month YYYY Question Answer Question 1: Section (a): Composition of Nucleosomes The nucleosome is the basic unit of the DNA and forms the building block of chromatin. Chromatin is a complex of the DNA and the cellular histone protein cores forming eukaryotic chromosomes. Structurally, the nucleosome core particle comprises 1.6 left-handed superhelical turns of DNA wound around a protein complex called the histone octamer, which consists of 2 copies each of the core histones attached to the central tetramer H3/H4. The latter is flanked by two H2A/H2B dimers (Kornberg 868). The histone octamer, therefore, is a set of the 8 basic proteins whose fundamental structure of a single molecule includes three
Homologous recombination (HR) can be explained as a process where DNA is exchanged or copied between two chromosomes or different regions of the same chromosome. The process requires homology between the exchanging DNA regions. Homologous recombination repairs DNA breaks, especially double stranded breaks (DSBs), stabilizes and repairs stalled forks. HR consists of a series of inter related pathways that function in repair of DNA breaks (Figure 4). Initially, stretches of single stranded DNA (ssDNA) are resected at the stalled forks or DSB ends which are quickly bound by replication protein A (RPA).
This breaks the DNA loop. The two AraC-arabinose complexes bind to the aral1 and aral2 sites which promotes transcription. When arabinose is present, AraC acts as an activator. If arabinose is present, it builds a complex: AraC + arabinose This complex is needed for RNA polymerase to bind to the promoter and transcribe the ara operon. Also for activation the binding of another structure to aral is needed: CRP+cyclic AMP so the activation depends on the presence of arabinose and cAMP.
9 #5: What effect do intervening repetitive base sequences have on human chromosomes?  Intervening repetitive base sequences account for 10-15% of human DNA. They are arrays of repeating short base sequences and their repetition varies. These repeating base sequences create individual variation of distances between recognition sites. P. 9 #6: What are “RFLPs” and what is their significance?
DNA sequence is the way of knowing the order of nucleotides within the DNA strands. And DNA Sequence Alignment is to compare two sequences to search for the homology of a newly one of the reference sequence for analyzing the relation between the two DNA sequences. This analysis could lead to know the causative agents of some diseases and the relation between the organisms. This paper is focused on the methods of DNA sequence Alignment and their analysis and related Algorithms. KEYWORDS DNA Sequence, DNA alignment, Alignment Algorithms.
There are two types of Nucleic acids, namely DNA known as deoxyribonucleic acid and RNA known as ribonucleic acid. The backbone of this Nucleic acid is the nucleotides. These nucleotides are made up of three components, namely the nitrogenous base, the pentose sugar, and the phosphate group. The Nitrogenous bases is made up of organic molecules adenine A, guanine G, cytosine C and
2. What major event occurs during interphase? DNA replication is the major event that occurs at the completion of the three phases in the interphase. Experiment 1: Following Chromosomal DNA Movement through Meiosis Data Tables and Post-Lab Assessment Trial 1 - Meiotic Division Without Crossing Over Pipe Cleaners Diagram: Take