http://insciences.org/article.php?article_id=8486&utm_source=feedburner&...

Howard Hughes Medical Institute (HHMI) researchers have made a surprising discovery about the molecular basis underlying spinal muscular atrophy (SMA), an often fatal neurodegenerative disease and the most common genetic cause of childhood mortality. The findings suggest that there may be a way to promote survival of neurons by helping a beneficial protein linger a little longer inside nerve cells.

Patients with SMA gradually lose the motor neurons in the spine that control most of their muscles. Researchers have known since the 1990s that the disease is nearly always linked to the absence or disruption of a gene known as SMN1 (Survival of Motor Neuron 1). A nearby gene, SMN2, is virtually identical to SMN1, and in principle could produce enough SMN protein to keep neurons healthy -- yet somehow fails to do so.

In the March 2010, issue of the journal Genes & Development, HHMI investigator Gideon Dreyfuss and Sungchan Cho, a postdoctoral researcher in his lab at the University of Pennsylvania School of Medicine, report on their work solving this mystery.

Dreyfuss and Cho found that most of the SMN protein produced from SMN2 is flagged for rapid degradation by a cellular waste-disposal system. Thus, the protein is cleared before it accumulates sufficiently to sustain the health of motor neurons. Blocking this degradation signal could therefore, in theory, be a way to treat SMA, Dreyfuss says.