Transgenesis and Cloning Transgenesis is the process of inserting a gene from one source into a living organism that would not normally contain the inserted gene. The gene can come from the same species (called Cisgenesis) or from a different species entirely. To facilitate the transfer of genes from one organism to another, often a Transgenic Organism with Recombinant DNA is created: -The first step in creating an organism capable of carrying out the transformation process is to isolate the required gene. This is done so using Restriction Enzymes, which target a specific gene sequence. The gene is often cut with staggered ends, called “Sticky Ends” which only allow specific and complementary gene sequences bond by base pairing.
This is the restriction enzyme and acts as “molecular scissors” cuts the two DNA chains at a specific area in the genome so that sections of DNA can be supplemented or detached. A piece of RNA known as guide RNA is the second key molecule. This consists of pre-designed RNA quite small in length sequence, consisting of about 20 bases, positioned within a longer RNA scaffold. The scaffold binds to DNA and the pre-designed sequence ‘guides’ Cas9 to the right part of the genome. ensuring that the Cas9 enzyme intersects at the right point in the genome.
Running head: DNA AND THE DOUBLE HELIX DESIGN DNA And The Double Helix Design J. Schultz University of Phoenix DNA And The Double Helix Design DNA, the commonly used acronym for deoxyribonucleic acid, is the carrier of the genetic code for most living organisms. DNA contains the genetic codes that determine eye color, hair color, and sometimes diseases. Each trait that passes from parent to offspring is the result of information carried by DNA. Possible Reasons For The Double Helix Shape DNA has a double helix shape that is functional and useful in several ways. According to The National Center For Biotechnology Information (2004): The chemical nature of the bases in double-stranded DNA creates a slight twisting force that gives DNA its characteristic gently coiled structure, known as the double helix.
The fragments are then joined together by DNA ligase, an enzyme that links the 3’ OH of one DNA fragment to the 5’ phosphate of another, forming a phosphodiester linkage. The opposite strand, the leading strand,
DNA Replication Carol Rowe WGU Biochemistry GRT1 Margie Hayes May 26, 2014 DNA DNA is made up of a sugar, a phosphate, with either a purine or a pyrimidine base, also called nucleotide subunits. Adenine and guanine are purines. Thymine and cytosine are pyrimidines. As you will see in the diagram, adenine bonds only with thymine and guanine bonds only with cytosine, they are connected by hydrogen bonding. Replication Fork In the DNA double helix Topolisomerase relieves the tension.
D) One strand is positively charged and the other is negatively charged. E) One strand contains only purines and the other contains only pyrimidines. 17) It became apparent to Watson and Crick after completion of their model that the DNA molecule could carry a vast amount of hereditary information in which of the following? AA A) sequence of bases B) phosphate-sugar backbones C) complementary pairing of bases D) side groups of nitrogenous bases E) different five-carbon sugars 37) What is the function of DNA polymerase III? CC A) to unwind the DNA helix during replication B) to seal together the broken ends of DNA strands C) to add nucleotides to the end of a growing DNA strand D) to degrade damaged DNA molecules E) to rejoin the two DNA strands (one new and one old) after replication 30) Eukaryotic telomeres replicate differently than the rest of the chromosome.
[edit] Eukaryotic pre-mRNA processingMain article: Post-transcriptional modification Processing of mRNA differs greatly among eukaryotes, bacteria, and archea. Non-eukaryotic mRNA is, in essence, mature upon transcription and requires no processing, except in rare cases. Eukaryotic pre-mRNA, however, requires extensive processing. [edit] 5' cap additionMain article: 5' cap A 5' cap (also termed an RNA cap, an RNA 7-methylguanosine cap, or an RNA m7G cap) is a modified guanine nucleotide that has been added to the "front" or 5' end of a eukaryotic messenger RNA shortly after the start of transcription. The 5' cap consists of a terminal 7-methylguanosine residue that is linked through a 5'-5'-triphosphate bond to the first transcribed nucleotide.
The nucleic acid, DNA has an individual structure that act as an information storage molecule that provides instuction for assembling proteins. DNA’s primary structure involves nucleotide sequences that are monomer repeats which form polynucleotide chains[1]. The Primary structure of DNA begins with one of the two different 5 -carbon sugar components either known as 2-deoxyribose. The particular sugar can then either be linked to a hetrocyclic base by an N – Glycosidic bond[2]. The hetrocyclic bases are derived from two different structures which inculde Purine and Pyrimidine.
Other genes with adjacent methylated CpG islands are transcriptionally silenced. The methyl groups in CpG islands occupy the major groove of DNA, and block the binding of transcription factors necessary to form transcription complexes. CpG islands are usually located upstream of promoter regions The bulk of methylated CpG dinucleotides are not adjacent to genes, and are found in repetitive DNA sequences located in heterochromatic regions of the genome, including the centromere. Methylation of these sequences contributes to silencing the transcription and replication of transposable elements such as LINE (long interspersed nuclear element) and SINE (short interspersed nuclear elements) sequences, which form a major part of the human genome. Heterochromatic methylation also maintains chromosome stability by preventing translocation and other chromosomal abnormalities.
Basically, DNA controls protein synthesis. The complex and precise process of protein synthesis begins within a gene, which is a distinct portion of a cell's DNA. DNA is a nucleic acid which is made up of repeating monomers, called nucleotides, and in the case of DNA, these individual monomers consist of a pentose sugar, a phosphoric acid and four bases known as adenine, guanine, cytosine and thymine. DNA is a double stranded polymer, which has a twisted ladder like