What would be the consequence of one base deletion at the beginning of the message for a protein

What would be the consequence of one base deletion at the...

Key Concepts

Deletion Mutation

A deletion mutation is a type of genetic mutation where one or more nucleotides are removed from the DNA sequence. When a single nucleotide is deleted, especially at the beginning of a coding region, it can have profound effects on the resulting protein due to changes in the coding sequence.

Reading Frame

The reading frame is the way nucleotides in mRNA are grouped into codons, each of which specifies an amino acid. Each group of three nucleotides represents one codon, so deleting one nucleotide can disrupt this grouping.

Frameshift Mutation

A frameshift mutation occurs when the deletion (or addition) of nucleotides is not in multiples of three, causing a shift in the reading frame. This shift changes the downstream codon composition, often leading to an entirely different sequence of amino acids.

Premature Termination

Due to the altered reading frame, a frameshift mutation may lead to the introduction of an early stop codon within the mRNA sequence. This premature termination results in a truncated protein that is likely nonfunctional or has altered functionality.

Transcript

00:01 Okay, in order to some of this question, we have to talk about a specific type of mutation, specifically the lesions, okay? a deletion occurs when there is, well, a removal or a legion, particularly, of one or more nucleotal basis, okay, in dna.

00:24 So the mobile of base in dna.

00:31 And this is, this can be very severe because remember that if you have, for example, c, c, c, u, a, u, g, g, okay? remember that if this is your m -r -na, if this is your m -na, let's make it a little bit longer, okay? c -c -a -a -a -u okay so this is the m -r -n -a and so if for example if you get a deletion you can delete this you for example this a deletion mutation okay or you can delete this g or the c from here or any base here okay and that's going to be a deletion okay and what is the consequence of this well remember that in mna, in mna, we're going to arrange all the bases as triplets, okay? as triplets.

01:33 And each triplet is called colon.

01:37 For example, this is one column, this is another column, this is another column, and this is another column.

01:45 Okay, aaa.

01:46 And let's just for dynamic purposes, let's change this to g.

01:52 Okay, so this is your mrna.

01:55 Now, in the process of translation, of translation, you're going to produce a polypeptide, practically, or a protein chain, okay? you have to use the genetic code that you can find it on google, and you're going to find a table in the genetic code where you're going to see that each column is going to code, for specific amino acid.

02:26 For example, cca, according to the genetic code, is going to code for proling.

02:33 Okay, for prolling.

02:35 Ugg, ugg is going to code for triptophan.

02:42 Gcc, gcc is going to code for alanine.

02:47 And finally, aaa is going to code for lysine.

02:51 So this is your normal amino acid sequence, okay? let's write again your mrna.

03:03 Okay.

03:04 Now what happens when you get a delugee? for example, here...