This animation illustrates how a small molecule binds to a protein. As a result of the binding, the protein alters its shape and becomes inactivated.
Rapamycin is a small molecule originally isolated from nature. It has antibiotic and immunosuppressive properties. It also allows two proteins which do not normally interact to bind together in the cell, which causes problems in the nutrient-sensing pathway.
A 3D animation showing how proteins in the cell are tagged for disposal and degraded by the proteasome.
Protease inhibitors prevent maturation of viral proteins inside HIV particles.
The PPAR-delta receptor activates certain genes in a muscle cell, resulting in the burning of fat.
Myosin II is one of the molecules involved in furrow formation in dividing cells. This animation shows how the molecule operates, and how furrowstatin blocks the mechanism and halts division of a cell.
The dengue virus's outer envelope proteins form symmetrical units and overlay the lipid envelope, capsid, and the RNA genome.
DNA is tightly packed in the nucleus of every cell. DNA wraps around special proteins called histones, which form loops of DNA called nucleosomes. These nucleosomes coil and stack together to form fibers called chromatin. Chromatin in turn forms larger loops and coils to form chromosomes.
The ribosome is a molecular factory that translates the genetic information in RNA into a string of amino acids that becomes a protein. Inside the ribosome, the genetic code of the RNA is read three letters at a time and compared with the corresponding code on a transfer molecule. When a match...
Messenger RNA (mRNA) carries DNA's genetic information to the ribosome, where it is translated into a sequence of amino acids. mRNA is fed into the ribosome, and it is positioned so that it can be read in groups of three letters, known as codons. Each mRNA codon is matched against the transfer...
Once the structure of DNA was discovered, the next challenge was determining how the sequence of letters coded for the 20 amino acids. In theory, one or two letters can only code for 4 or 16 amino acids, respectively. A scheme using three letters, a triplet code, is the minimum necessary to...
Cone snails have evolved many different toxins for different uses. Total molecular biodiversity may number in the millions.
Mutations in key genes can lay waste to the nervous system. By studying large families predisposed to developing these genetic disorders, scientists can identify the responsible altered gene.
To understand life's processes, perturb them. How a process responds to an insult can provide clues about normal function or mimic a specific disease state.
Scientists now have the ability to create millions of new molecules. How do they test whether any of these molecules are useful?
In four lectures, Nobel laureate Thomas R. Cech, PhD, discusses the ability of RNA to act as more than just an intermediary between DNA and proteins.
Discovery of RNA's catalytic activity led to unexpected spin-offs, including a new scenario for the origin of life.
The chromosome ends, or telomeres, are necessary for DNA stability and replication.
Learn about the structure and function of this fascinating cellular machine.
An activity in which students analyze amino acid data and draw conclusions about the evolution of coat color phenotypes in different rock pocket mouse populations.
A hands-on activity in which students construct models of sickle-cell hemoglobin fibers inside red blood cells to illustrate how changes in the structure of a protein can affect cell shape. Students are then asked to relate these changes to disease symptoms.
Topics include: Gene expression, RNA structure and function, transcription, RNA processing, translation, and post-translational events.
The drug Gleevec binds to and inactivates BCR-ABL, a mutant kinase that causes chronic myeloid leukemia.
Mutations in the BCR-ABL gene can cause resistance to Gleevec, but another drug, dasatinib, can be used instead.
Understanding that cancer is caused by mutations in genes that regulate cell proliferation has led to the development of targeted drug therapies.