Cornell University researchers have discovered the 3-D crystal structure of a protein, human CD38, which may lead to important discoveries about how cells release calcium - a mineral used in almost every cellular process.
The findings also may offer insights into mechanisms involved in certain diseases, ranging from leukemia to diabetes and HIV-AIDS.
Levels of the protein climb, for reasons unknown, when people fall ill, making human CD38 a marker for these diseases.
As one example, researchers have shown that CD38 interrupts an interaction between the AIDS virus and its point of entry into cells -- a protein receptor called CD4. By looking at CD38's 3-D structure, the Cornell researchers identified a peptide, an organic compound composed of amino acids, that they believe may play a role in interrupting the interface between CD4 and HIV-AIDS.
The findings, published in the journal Structure (Vol. 13, Sept. 2005), mark a major step toward designing drugs that could inhibit processes related to certain diseases. Knowing the protein's structure also opens the door to understanding CD38's many functions related to key biological processes about which researchers know very little.
"For example, the mechanism of how a cell mediates calcium release is largely unknown," said the paper's senior author, Quan Hao, director of the Macromolecular Diffraction Facility (MacCHESS), the biomedical research arm of the Cornell High Energy Synchrotron Source (CHESS). "So this is a very fundamental question for biologists."