Question $2$ Gene Expression $-$ Translation

This question is based on the same organism as described in question $1.$

The LG gene is expressed during development in the bottom half of both the tail and abdomen sections of the embryo. If the LG protein joins with the ABD protein, this complex can bind to the DNA of genes responsible for leg development and cause legs to form in the abdomen segment. If the LG protein does not join with the ABD protein, there will be no legs formed in the abdomen segments. Both strands of the LG protein need to be able to interact with the DNA for legs to form. Similarly, both strands of the LG protein are needed for binding with the ABD protein. The structures of the proteins and their interaction with each other and DNA are shown in Figure $2$A$.$ The stars indicate the cysteines that are responsible for the disulfide bonds between the strands of the LG protein.

A scientist has identified two mutations, LG$1$ and LG$2.$ In an organism homozygous for LG$1($LG$1/$LG$1),$ there are no legs in the abdomen region. Similarly, in an organism homozygous for LG$2($LG$2/$LG$2),$ there are no legs in the abdomen region. These substitution mutations and the codons in the DNA sequence that are changed are shown in Figure $2$B$.$

Figure $2$: Information about wildtype LG gene and mutations $2$A$.$ Wildtype Gene for LG Protein

$2$B$.$ Location of Mutations for LG Protein

Question $2$A Compare the lengths of the fully mature mRNA transcripts for LG$1,$ LG$2$ and the wildtype gene. Explain your reasoning.

Question $2$B Compare the lengths of the proteins produced by LG$1,$ LG$2$ and the wildtype gene. Explain your reasoning.

Include a picture to support your answer for $2$C and $2$D$.$

Question $2$C In a heterozygous organism with LG$1$ and wildtype alleles, would the organism have legs? Would LG$1$ be recessive or dominant to the wildtype allele? Use specific information from the picture and your knowledge of protein structure and function to justify your answer. Be sure to explain which parts of the protein would or would not retain function, how you know, and how this affects your answer. Question $2$DIn a heterozygous organism with LG$2$ and wildtype alleles, would the organism have legs? Would LG$2$ be recessive or dominant to the wildtype allele? Use specific information from the picture and your knowledge of protein structure and function to justify your answer. Be sure to explain which parts of the protein would or would not retain function, how you know and how this affects your answer.

Question $2$E: This gene has three alleles. If you were to use one of your equations from week $4$ on inheritance to predict the types of gametes $($egg or sperm$)$ produced by a single parent and this was one of the three genes you were considering, would you need to change your equation. Explain your reasoning.