Epigenetics: genetic control beyond DNA sequence

— If every cell in an organism has the same genetic program, how can there be so many different types of cells in one body? The answer lies in the fact that not all genes are turned on or expressed in every cell. Determining which genes are turned on and off is critical for generating the diverse types of cells found in the body. Different types of cells express different genes. How does a cell control which parts of the genome are read and which are ignored? One way this can happen is through epigenetic modifications, changes to our genetic information that don’t involve changes in the DNA sequence. The growing field of epigenetics explores how cells use non-sequence changes to exert control over the way the genome is interpreted, as well as how these changes are passed on from one generation to the next. Continue reading Epigenetics: genetic control beyond DNA sequence

Mighty Mitochondria and Neurodegenerative Diseases

— While sitting in your elementary school classroom or making some amorphous jelly mold studded with jelly beans, you may have heard the phrase “mighty mitochondria” from your studies on the cell structures. More than just a catchy alliteration, this phrase accurately describes one of the most fundamental components of the cells that make up our bodies. Mitochondria, often referred to as the “powerhouses of the cell”, were first discovered in 1857 by physiologist Albert von Kolliker, and later coined “bioblasts” (life germs) by Richard Altman in 1886. The organelles were then renamed “mitochondria” by Carl Benda twelve years later. It wasn’t until more than half a century had passed since their discovery that the function of mitochondria began to be unraveled. Continue reading Mighty Mitochondria and Neurodegenerative Diseases