Question

modify the following sentence to represent the two types of frameshift mutations.
the red fox ran
frameshift addition
the following chart shows the changes that
have occured to a rna strand and how it has
affected the protein sequence. determine the
mutation and explain your reasoning.
original\tggu\tauu\tcgu\tugu\taaa
protein\tgly\tile\targ\tcys\tlys
mutated\tggu\tauc\tcgu\tugu\taaa
protein\tgly\tile\targ\tcys\tlys
frameshift deletion
create it!
create your own example of a sentence using
3-letter words. then change the sentence to
represent a missense (point) mutation.

Answer:

Part 1: Frameshift Mutations on "THE RED FOX RAN"

Frameshift Addition (Insert a letter, shifting the "reading frame" of 3 - letter "words")

Let's split the original sentence into 3 - letter "words": $THE\ RED\ FOX\ RAN$ (assuming spaces are just for separation, and we treat each 3 - letter group as a "codon" - like unit). Let's insert a letter, say "X", after the first "T" in "THE". Now the sentence becomes: $TXH\ ERE\ DFO\ XRA\ N$ (we re - group into 3 - letter words: $TXH\ ERE\ DFO\ XRA\ N$; note that the last "N" is left, but the key is the shift. A more proper way: original "THE" (T - H - E), insert "X" after T: T - X - H - E -... Now re - grouping: TXH (T - X - H), ERE (E - R - E), DFO (D - F - O), XRA (X - R - A), N (leftover, but for the sake of the model, we can adjust. Alternatively, insert a letter in the middle of a word. Let's take the original sentence as a sequence of letters: T - H - E - R - E - D - F - O - X - R - A - N. Let's insert a "Z" after the "E" in "RED" (so after the 5th letter: T - H - E - R - E - Z - D - F - O - X - R - A - N). Now re - grouping into 3 - letter words: $THE\ R EZ\ DFO\ XRA\ N$ (wait, no, correct re - grouping: T - H - E (THE), R - E - Z (REZ), D - F - O (DFO), X - R - A (XRA), N (leftover). So the modified sentence for frameshift addition could be: $THE\ REZ\ DFO\ XRA\ N$ (or a more concise version: "THE REZ DFO XRA N" to show the shift).

Frameshift Deletion (Delete a letter, shifting the "reading frame")

Take the original sentence's letter sequence: T - H - E - R - E - D - F - O - X - R - A - N. Let's delete the "E" in "RED" (the 5th letter). Now the sequence is: T - H - E - R - D - F - O - X - R - A - N. Re - grouping into 3 - letter words: $THE\ RDF\ OXR\ AN$ (T - H - E (THE), R - D - F (RDF), O - X - R (OXR), A - N (leftover, but we can present it as "THE RDF OXR AN" to show the shift).

Part 2: Analyzing the RNA and Protein Mutation

Step 1: Compare Original and Mutated RNA

Original RNA codons: $GGU,\ AUU,\ CGU,\ UGU,\ AAA$
Mutated RNA codons: $GGU,\ AUC,\ CGU,\ UGU,\ AAA$

Step 2: Analyze the Change

We see that only the second codon changes: from $AUU$ to $AUC$.

Step 3: Check the Protein Sequence

Original protein for $AUU$: $ILE$ (Isoleucine)
Mutated protein for $AUC$: $ILE$ (Isoleucine)

Step 4: Determine Mutation Type

Since the change in the RNA codon ($AUU
ightarrow AUC$) does not change the amino acid (both code for Isoleucine), this is a silent mutation. A silent mutation is a type of point mutation where a change in the DNA (or RNA) codon does not result in a change in the amino acid sequence of the protein.

Part 3: Missense Mutation Example

Step 1: Create a 3 - letter word sentence

Let's create a sentence: $THE\ CAT\ RAN$ (split into 3 - letter words: $THE,\ CAT,\ RAN$).

Step 2: Introduce a Missense Mutation

A missense mutation is a point mutation that changes one amino acid (or in our sentence, one letter in a 3 - letter word) to another, changing the "meaning" (the word). Let's change the "A" in "CAT" to "A" to "O", so the word becomes "COT". Now the sentence is: $THE\ COT\ RAN$.

In terms of codons (if we were to model RNA), suppose the original codon for "CAT" (as a protein - like unit) was, say, $CAU$ (coding for Histidine, but in our simple sentence model, we just change the letter). The change from "CAT" to "COT" is like a missense mutation because one letter (nucleotide) change has changed the word (amino acid - equivalent in our model).

Final Answers

• Frameshift Addition Sentence (example): $THE\ REZ\ DFO\ XRA\ N$ (or other valid shifted sentence)
• Frameshift Deletion Sentence (example): $THE\ RDF\ OXR\ AN$ (or other valid shifted sentence)
• Mutation Type (from RNA/Protein table): Silent Mutation
• Missense Mutation Example Sentence: Original: $THE\ CAT\ RAN$; Mutated: $THE\ COT\ RAN$