Proteins, Proteins Everywhere

By Gleeson, Frank; Pearson, Mark | The World and I, May 2002 | Go to article overview

Proteins, Proteins Everywhere


Gleeson, Frank, Pearson, Mark, The World and I


The massive undertaking to study the entire set of human proteins will clarify the molecular basis of many diseases, leading to more reliable diagnostics and more effective treatments.

Since the early 1990s, the Human Genome Project has been devoted to the scientific study of our genome--that is, the genetic material in a complete set of our chromosomes. The project's goal has been to identify all human genes, find their locations on the chromosomes, and discover their role in our lives. In so doing, it is helping us determine how various genes are associated with particular illnesses, such as cystic fibrosis, Alzheimer's disease, and forms of cancer. Likewise, other research efforts have undertaken detailed analyses of the genomes of various animals, plants, and microbes. As a result, public attention has been drawn to the field known as genomics.

On the molecular level, the genetic material consists of long, double- helical molecules of DNA (deoxyribonucleic acid) made from small building blocks (nucleotide pairs or base pairs). Genes are those segments of the DNA strands that encode molecules known as RNA (ribonucleic acid), many of which in turn act as templates for the synthesis of proteins. Thus the focus of the Human Genome Project has been to determine the precise sequence of base pairs in the DNA of each chromosome, and to identify the DNA segments that correspond to genes.

Considering that there are about 3 billion base pairs in the human genome, the task of sequencing them has been awesome. Yet, thanks to amazing developments in biotechnology and computing power, researchers have brought this task to near completion [see "Unraveling the Human Thread of Life," The World & I, September 2001, p. 136]. The number of protein-coding genes in the human genome is still unclear, but computer-assisted analyses of the DNA sequences have suggested that the figure is somewhere between 25,000 and 40,000.

Whatever the case, it is not the genes but the proteins they encode that are direct participants in most of our body functions. For instance, proteins in our muscles help us lift heavy loads; those in the eyes help create images of what we see; those in the brain process nerve impulses that allow communication with the rest of the body. Many proteins, known as enzymes, act as catalysts for various cellular reactions; others contribute to the structures of our tissues and organs. Some proteins are hormones, carrying signals between distant body parts; others are antibodies that fight infectious agents. On the other hand, if a gene is mutated, it may direct the synthesis of a defective protein, which may then lead to an illness.

Thus, to understand how our body operates in health and disease, we need to probe the elaborate functions of proteins. Given their tremendous complexity and variety, past research has been restricted to examining them one at a time or in small clusters. Now, however, with the taste of success on the level of the human genome, and with continuing technological developments, biologists are willing to tackle the far more complicated challenge of investigating the full set of proteins in the body.

Introducing proteomics

The entire collection of proteins encoded by the genome of an organism is known as the proteome, and the new frontier of research that involves the system-wide study of these proteins is called proteomics. The aim of proteomics is to identify all the proteins in the selected organism, find their structures, and determine what they really do.

The complexity of proteomics begins with the complexity of protein structure. While a piece of DNA is constructed from four types of nucleotides that are specifically paired to generate a double-helical shape, a protein is made from 20 types of building blocks (amino acids) that are strung together and elaborately folded. Each protein has a unique three-dimensional (3-D) structure that is based on (but not easily predictable from) the sequence of amino acids. …

The rest of this article is only available to active members of Questia

Already a member? Log in now.

Notes for this article

Add a new note
If you are trying to select text to create highlights or citations, remember that you must now click or tap on the first word, and then click or tap on the last word.
One moment ...
Default project is now your active project.
Project items

Items saved from this article

This article has been saved
Highlights (0)
Some of your highlights are legacy items.

Highlights saved before July 30, 2012 will not be displayed on their respective source pages.

You can easily re-create the highlights by opening the book page or article, selecting the text, and clicking “Highlight.”

Citations (0)
Some of your citations are legacy items.

Any citation created before July 30, 2012 will labeled as a “Cited page.” New citations will be saved as cited passages, pages or articles.

We also added the ability to view new citations from your projects or the book or article where you created them.

Notes (0)
Bookmarks (0)

You have no saved items from this article

Project items include:
  • Saved book/article
  • Highlights
  • Quotes/citations
  • Notes
  • Bookmarks
Notes
Cite this article

Cited article

Style
Citations are available only to our active members.
Buy instant access to cite pages or passages in MLA, APA and Chicago citation styles.

(Einhorn, 1992, p. 25)

(Einhorn 25)

1. Lois J. Einhorn, Abraham Lincoln, the Orator: Penetrating the Lincoln Legend (Westport, CT: Greenwood Press, 1992), 25, http://www.questia.com/read/27419298.

Cited article

Proteins, Proteins Everywhere
Settings

Settings

Typeface
Text size Smaller Larger Reset View mode
Search within

Search within this article

Look up

Look up a word

  • Dictionary
  • Thesaurus
Please submit a word or phrase above.
Print this page

Print this page

Why can't I print more than one page at a time?

Help
Full screen

matching results for page

    Questia reader help

    How to highlight and cite specific passages

    1. Click or tap the first word you want to select.
    2. Click or tap the last word you want to select, and you’ll see everything in between get selected.
    3. You’ll then get a menu of options like creating a highlight or a citation from that passage of text.

    OK, got it!

    Cited passage

    Style
    Citations are available only to our active members.
    Buy instant access to cite pages or passages in MLA, APA and Chicago citation styles.

    "Portraying himself as an honest, ordinary person helped Lincoln identify with his audiences." (Einhorn, 1992, p. 25).

    "Portraying himself as an honest, ordinary person helped Lincoln identify with his audiences." (Einhorn 25)

    "Portraying himself as an honest, ordinary person helped Lincoln identify with his audiences."1

    1. Lois J. Einhorn, Abraham Lincoln, the Orator: Penetrating the Lincoln Legend (Westport, CT: Greenwood Press, 1992), 25, http://www.questia.com/read/27419298.

    Cited passage

    Thanks for trying Questia!

    Please continue trying out our research tools, but please note, full functionality is available only to our active members.

    Your work will be lost once you leave this Web page.

    Buy instant access to save your work.

    Already a member? Log in now.

    Oops!

    An unknown error has occurred. Please click the button below to reload the page. If the problem persists, please try again in a little while.