Distinct characteristics are not only an end result of the DNA sequence but also of the cell’s internal system of expression orchestrated by different proteins and RNAs present at a given time. DNA encodes for many possible characteristics, but different types of RNA aided by specialized proteins sometimes with external signals express the needed genes. Control of gene expression is of vital importance for an eukaryote’s survival such as the ability of switching genes on/off in accordance with the changes in the environment (Campbell and Reece, 2008). Of a cell’s entire genome, only 15% will be expressed, and in multicellular organisms the genes active will vary according to their specialization. (Fletcher, Ivor & Winter, 2007).
The amount of information encoded by the genes within a cell is enormous, although some will never be expressed while others occasionally during its life cycle. For example some genes that encode for ribosomal RNA are being expressed continuously because they are responsible with the formation of proteins in the cell’s cytoplasm. Specific RNA molecules and proteins are expressed in all cells at all times, their genes going under the name of housekeeping genes. They are responsible with the maintenance of the cells and can aid geneticists recognize their function (Brown, 2011).
A specialized cellular molecule copies a given sequence of DNA whose end product will contribute to its function. DNA is a long molecule that usually can be found in a condensed state. Specialized types of proteins called histones wrap the DNA, forming nucleosomes, and thus occupying a smaller volume in the nucleus. There are 2 types of nucleosomes, their importance being in that they tell what will be expressed or not. Euchromat...
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... information needed to stimulate normal cell growth. Failure can lead to the onset of cancer. (Campbell, Reece, Urry, Cain, Wasserman, Minorsky and Jackson, 2008)
Works Cited
1. Campbell N. A., Reece L. A., Cain M. L., Wasserman S. A., Minorsky P. V. and Jackson R. B. (2008). Regulation of Gene Expression
2. (website – Theresa Philips, Ph.D. ( write science right ) c. 2008 Nature Education
Citation: Philips, T. (2008) Regulation of Transcription and gene expression in Eukaryotes. Nature Education 1(1)
Accessed: 02/11/2013 www.nature.com/scitable/topicpage/regulation-of-transcription-and-gene-expression-in-1086 Hartl Daniel L. 2009 Genetics
Analysis of Genes and Genomes
Added to Library: 18 Nov 2013Last Updated: 18 Nov 2013
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Russel Peter J. 2010 iGenetics
A molecular approach
Miller, Kenneth R. and Joseph S. Levine. “Chapter 12: DNA and RNA.” Biology. Upper Saddle River: Pearson Education, Inc., 2002. Print.
Takahashi, Y., et al. “Analysis of Promoter binding by the E2F and pRB Families In Vivo: Distinct E2F Proteins Mediate Activation and Repression.” Genes 14 (2000): 804-816.
The operon is a set of coding regions of DNA clustered together that includes structural genes and it is under the control of a single regulatory region. The operator regulates transcription, which is a repressor protein. When the operator binds to a segment of the regulatory region, transcription is shut down.
Altman, Lawrence K. ìShark Substance Found to Limit Tumor Growth.î New York Times 1 May 1996: A15.
Hall, Linley Erin. “Understanding Genetics DNA and RNA.” New York: The Rosen Publishing Group, Inc., 2011. Print. 01 Apr. 2014.
Cancer is the term used to describe a group of diseases consisting of hundreds of ailments and although there exists so many different types of cancer, they all begin in a similar way. The body is made up of over a trillion cells, and cancer is the uncontrolled growth of malfunctioning cells in the body (Dawson, 1996). “Normal body cells grow, divide, and die in an orderly fashion. During the early years of a person’s life, normal cells divide faster to allow the person to grow. After the person becomes an adult, most cells divide only to replace worn-out or dying cells or to repair injuries” (American Cancer Society, 2012).
Do you have any transcription factors in your body? I sure hope the answer is yes, because otherwise, you're going to have a hard time keeping your cells running!
There are 4 main mechanisms of modification and regulation of gene expression; DNA methylation, Chromatin Remodeling (architecture), Histone Modification and RNAi (interference/interactions)
Tumors are formed by the alteration of the body’s own cells. This can be caused by environmental factors such as radiation, like UV exposure, chemicals or viruses 1. These can disrupt genes that control growth and cause an increase in cell division and proliferation. Proto-oncogenes are those genes that control normal but essential cell processes that keep cell growth and death in check. Two important categories are apoptosis genes, which regulate cell death, and tumor suppressor genes, which decrease cell propagation 1 . If these genes were mutated to the point where they cannot produce a functioning protein, cell division would continue far past what it was supposed to and unhealthy cells would be allowed to live and continue to multiply. This is what creates a malignant tumor. Certain conditions in the body can also promote the growth of cancer cells. One of these is a deficiency of natural killer (NK) cells, which are able to kill cancer cells by creating a pore in the cell membrane with perforin and releasing granzymes into the cell. Low levels of perforin allow for tumor growth 1. Chronic inflammation can also ...
... to RNA and the translation to proteins, as well as gene expression. Noble does an excellent job of presenting an opposing view to the central dogma of biology, using metaphors to attempt to make his differing views clearer to the reader. While Noble does use a lot of scientific evidence to support his opinions, his use of metaphors is overwhelming and it can easily distract the reader from the point that he is trying to make. ,Nobles’ explanations of gene expression help the reader to understand the process of evolution, giving a more or less clear view as to how redundancy in the genome can lead to variation. Noble neglects, however, to expand upon natural selection or any other ideas related to evolution. If these ideas were present, they were lost somewhere between the overwhelming use of metaphors and the overly detailed explanations of cell signaling processes.
Cancer has been seen in humans as one the most potentially fatal disease for thousands of years and only in the recent couple of hundred years have we discovered that most information necessary to bring us to today’s understanding and knowledge (Kenny 2007, Weinberg 1996) was achieved by extensive research of cells, DNA, and epidemiology studies. As we know, currently cancer is acknowledged as having over a hundred different diseases, and is known to be the result of mutations of the genes and almost similar DNA which are responsible for the amount of cell division and production (Kenny 2007). Restraint of cell growth modulators can be a direct lead and result of certain tumours being developed and subsequently allow these tumours to acquire the ability to attack and occupy the bloodstream and essentially be able to travel via the bloodstream to other parts and organs in human bodies which is known as metastasis (Loeb et Al 2003). Once this has occurred , the cancer is then categorized as malicious and becomes a dangerous and serious threat to the carrier (Weinberg 1996). In this essay I will describe and explain the process of this and how our genes mutate and lead to metastasis of cancer cells.
Micro RNAs (miRNA’s) are created from microgenes and are a molecule that is aproximetly 22 base pairs in length, they are thought to coordinate the expression of genes that are protein coding in eukaryotes. Over 1000 have been discovered and they seem to compromise a secondary level of control that is likely to coordinate the genome function in humans and other complex organisms (Elliot and Elliot)
DNA (deoxyribonucleic acid) is a self-replicating molecule or material present in nearly all living organisms as the main constituent in chromosomes. It encodes the genetic instructions used in the development and functioning of all known living organisms and many viruses. Simply put, DNA contains the instructions needed for an organism to develop, survive and reproduce. The discovery and use of DNA has seen many changes and made great progress over many years. James Watson was a pioneer molecular biologist who is credited, along with Francis Crick and Maurice Wilkins, with discovering the double helix structure of the DNA molecule. The three won the Nobel Prize in Medicine in 1962 for their work (Bagley, 2013). Scientist use the term “double helix” to describe DNA’s winding, two-stranded chemical structure. This shape looks much like a twisted ladder and gives the DNA the power to pass along biological instructions with great precision.
Because cells are the ‘basic unit of life’, the study of cells, cytology, can be considered one of the most important areas of biological research. Almost every day on the evening news, we are told about new discoveries in cell biology, such as cancer research, cloning, and embryology. (https://highered.mheducation.com/sites/0073031216/student_view0/exercise3/the_importance_of_cell_biology.html)