Frameshift Question

Discussion of all aspects of biological molecules, biochemical processes and laboratory procedures in the field.

Moderators: honeev, Leonid, amiradm, BioTeam

Post Reply
Posts: 1
Joined: Sat Feb 06, 2010 7:26 pm

Frameshift Question

Post by billymaize » Sat Feb 06, 2010 7:40 pm

In Tay Sachs Disease, a change in a base pair knocks out the protein function. The protein made is shorter, while each mutant mRNA is 30% longer than normal mRNA. A deletion of a base pair causes this situation.

I am wondering how a deletion in the frame shift can cause transcription resulting in longer mRNA and then leading to a shorter protein during translation. I know that an deletion can result in a premature stop codon, but shouldn't the termination area of the template DNA still be largely unaffected? Can anybody explain?

User avatar
Inland Taipan
Inland Taipan
Posts: 5345
Joined: Thu Jan 20, 2005 8:14 pm
Location: Nashville, TN

Post by mith » Mon Feb 08, 2010 5:12 am

more info if you search "transcription termination"
Living one day at a time;
Enjoying one moment at a time;
Accepting hardships as the pathway to peace;

User avatar
Posts: 442
Joined: Fri Feb 15, 2008 5:38 pm
Location: Philomath, Oregon, USA

Re: Frameshift Question

Post by jonmoulton » Mon Feb 08, 2010 4:16 pm

I don't know if this is the case in Tay-Sachs, but here is one way a point mutation could result in both a shorter protein and a longer mRNA. If the mutation occurs at a splice junction or a splice-regulatory site, the removal of an intron may be deactivated. In that case, the intron appears in the mRNA, increasing its length. An in-frame stop codon in the intron may result in translation of a shorter polypeptide.

Post Reply

Who is online

Users browsing this forum: No registered users and 9 guests