Saturday, January 9, 2010

The Cells of CF

I thought this article did a good job explaining what is going on in the cells of a CFer, cause remember, it's not a lung disease. Cystic Fibrosis is a CELL disease.


Inhibition of Proteostasis Restores Ion Channels in CF Cells

Tuesday January 5, 2010

Our cells are full of enzymes that mediate activities like growth, metabolism, replication,transcription and cell signalling. They are all unique in their structure, and have evolved over time to perform the specific functions for which they are made. Some enzymes are hydrophillic(water-loving, or water soluble) and remain in the cytoplasm of the cell, while others arehydrophobic, thus more lipophillic. The lipophillic enzymes are generally found embedded in cell membranes and tend to have roles such as mediating the transport of small molecules and ions across the membrane. Cystic fibrosis transmembrane conductance regulator (CFTR) is one such membrane protein.

In order to study its structure and function, it is necessary to first purify a protein. Like all hydrophobic transmembrane proteins, study of CFTR is hindered because it is difficult to purify and study in a stable form. However, it has been determined that mutations in the gene encoding CFTR result in an improper protein structure, that folds incorrectly, is recognized as defective by cellular machinery, and is destroyed.

Without CFTR, chloride ion transport in the lungs is hindered, resulting in a mucus buildup characteristic of the disease. Efforts to treat CF by altering the gene or protein structures in patients have not been terribly effective, but last month a study was published that showedrestoration of ion transport could be achieved by controlling the actions of a class of enzymes responsible for proteostasis (destruction of proteins) called histone deacetylases (HDACs). A compound called suberoylanilide hydroxamic acid (SAHA), already approved by the FDA for treatment of lymphoma, was able to restore up to 28% of channel activity in isolated cell cultures from CF patients. The authors, Hutt et al., postulated that by preventing destruction of imperfect proteins, those polymorphisms that are not completely disfunctional can restore some ion exchange capacity in cell membranes.

Full article at http://biotech.about.com/b/2010/01/05/inhibition-of-proteostasis-restores-ion-channels-in-cf-cells.htm


Make sense??