Protein Misfolding and Degenerative Diseases_Reynaud 2010

Protein Misfolding and Degenerative Diseases_Reynaud 2010 -...

Info icon This preview shows pages 1–2. Sign up to view the full content.

By: Enrique Reynaud, Ph.D. ( Instituto de Biotecnologia, Universidad Nacional Autonoma de Mexico ) © 2010 Nature Education Protein Misfolding and Degenerative Diseases Figure 1 An error in protein conformation can lead to disease. What are the genetic and molecular causes for incorrectly formed proteins? Current advances in medicine and technology are making our lives longer. Sadly, as our life expectancy increases, the chances of getting a degenerative disease like Alzheimer's, Parkinson's, or diabetes also increases. Why is this? As incredible as it might sound, these diseases are caused not by bacteria or viruses but rather by something conceptually quite simple: incorrect protein folding. Introductory biology courses teach us that proteins are essential for the organism because they participate in virtually every process within the cell . Therefore, if their function is impaired, the consequences can be devastating. As we age, mutations and thermodynamics (as well as some external factors) conspire against us, resulting in the misfolding of proteins. How does this happen? What are the genetic and molecular causes for incorrect folding of proteins, and what is their relationship to aging? Protein Function and Three-Dimensional Structure Our modern understanding of how proteins function comes from almost 200 years of biochemical studies. Biochemistry is the science that studies the chemical processes in living organisms. Using di ! erent experimental models, biochemists demonstrated that most of the cell's chemical reactions and structural components are mediated or supplied by proteins. These experiments revealed that proteins are crucial for proper cell function. Actually the word "protein" comes from the Greek proteios , which means "first" or "foremost," reflecting the importance of these molecules. In 1917 the German chemist Hermann Staudinger proposed that organic molecules such as proteins were organized in polymers, giant molecules made of small-molecule constituents linked together by chemical bonds in long chains. This idea contradicted the prevailing hypothesis, and it took some years for biochemists to accept it. Today researchers know that proteins are long polymers made out of a set of twenty small constituents called amino acids (Figure 1). How are proteins made in the cell? The answer to this question took decades of study and the birth of a new scientific discipline: molecular biology. Many experiments had shown that DNA is the vehicle of genetic information, and that DNA contains the information to make proteins. While discovering that DNA is itself a long polymer made out of four di ! erent types of small molecules called nucleotides, scientists realized that genetic information is transferred from a language system of four letters (nucleotides) in DNA to a language system of twenty (amino acids) in proteins.
Image of page 1

Info icon This preview has intentionally blurred sections. Sign up to view the full version.

Image of page 2
This is the end of the preview. Sign up to access the rest of the document.

{[ snackBarMessage ]}

What students are saying

  • Left Quote Icon

    As a current student on this bumpy collegiate pathway, I stumbled upon Course Hero, where I can find study resources for nearly all my courses, get online help from tutors 24/7, and even share my old projects, papers, and lecture notes with other students.

    Student Picture

    Kiran Temple University Fox School of Business ‘17, Course Hero Intern

  • Left Quote Icon

    I cannot even describe how much Course Hero helped me this summer. It’s truly become something I can always rely on and help me. In the end, I was not only able to survive summer classes, but I was able to thrive thanks to Course Hero.

    Student Picture

    Dana University of Pennsylvania ‘17, Course Hero Intern

  • Left Quote Icon

    The ability to access any university’s resources through Course Hero proved invaluable in my case. I was behind on Tulane coursework and actually used UCLA’s materials to help me move forward and get everything together on time.

    Student Picture

    Jill Tulane University ‘16, Course Hero Intern