Question $3$ Gene Expression $-$ Transcription

The transcripts and proteins of one of the genes responsible for leg development $($JNT$)$ that is regulated by the LG and ABD proteins is shown below $($Figure $3).$ The transcripts and proteins produced by the wildtype JNT gene are shown both in the nucleus and in the cytoplasm in Figure $3$A$.$ Scientists have identified several mutations in this gene and investigated the RNAs and proteins that are produced and their location $($Figure $3$B$-$D$).$ Note that $3$A$,$B$,$C show the homozygotes while $3$D is a heterozygote.

Figure $3$: Picture of transcripts and proteins produced by wildtype and mutant JNT genes.

For each mutation, use the picture to:

$-$ Describe what step in the process of transcription or transcription processing is being affected in the mutant $($be specific$).$ Explain your reasoning.

$-$ Name one specific protein function $($function NOT necessarily protein name unless we have referenced it in class$)$ that could be mutated and explain how that could affect this step in the process of transcription or transcription processing.

$-$ Support both parts of your answer with the evidence provided in the picture and your knowledge of transcription.

Be sure to zoom in to $500\backslash \%$ to catch all of the details.

Question $3$A Mutation A

Question $3$B Mutation B

Question $3$C Mutation C