SI
SI
discoversearch

We've detected that you're using an ad content blocking browser plug-in or feature. Ads provide a critical source of revenue to the continued operation of Silicon Investor.  We ask that you disable ad blocking while on Silicon Investor in the best interests of our community.  If you are not using an ad blocker but are still receiving this message, make sure your browser's tracking protection is set to the 'standard' level.
Pastimes : BS Bar & Grill - Open 24 Hours A Day -- Ignore unavailable to you. Want to Upgrade?


To: LindyBill who wrote (3974)12/9/2002 1:25:53 PM
From: Condor  Respond to of 6901
 
Bill...from Win Smith's thread. Something you'd appreciate I believe
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
Jewels That May Help Explain Behavioral Disorders Found Among "Junk" DNA
sciencedaily.com

The existence of smnRNAs has been known for some time. Until recently, they have been generally dismissed as
unimportant. New studies are finding that they are actually quite abundant and involved in a wide variety of
biological processes. As a result, some scientists are beginning to speculate that they may represent an entirely new
class of gene and type of gene activity.

McInnes cited the theoretical work of John Mattick and Michael Gagen at the University of Queensland in
Brisbane. Last year they published a lengthy paper in Molecular Biology and Evolution in which they argued that,
rather than being useless, smnRNAs and introns – the sequences in the genome between genes that code for
proteins that have been called junk DNA – form a powerful network that can turn ordinary genes on and off at the
proper times.

"It appears that smnRNA may be especially relevant for understanding behavioral differences," McInnes said,
"because they appear to be particularly enriched in the brain. They represent a swift and energy efficient means of
regulating gene expression and may be especially important for rapid regulatory events."

Lack of expression of an smnRNA has already been strongly associated with one neuropsychiatric disorder,
Prader Willi syndrome, McInnes reported. Prader-Willi syndrome is characterized by abnormally poor muscle tone
and feeding difficulties in early infancy, followed by excessive eating and gradual development of morbid obesity. It
is also accompanied by cognitive impairment.

In the initial trial of their new screen, the Mt. Sinai researchers identified a possible smnRNA molecule produced by
an intron of the human corticotrophin-releasing hormone gene. Corticotrophin releasing hormone (CRH) plays a
key role in the response of humans and other mammals to external threats. It acts at a number of sites in the
nervous system to control automatic, behavioral and immunological responses of stress. Alterations in CRH neural
activity appear to contribute to a number of mental illnesses including depression, anxiety disorders and anorexia
nervosa. In addition, the CRH smnRNA appears to form a complimentary match with a sequence in an
untranslated region associated with a receptor, called the NMDA-glutamate receptor, which is widely implicated in
schizophrenia and other degenerative neurological disorders.

Message 18316718