You are studying FIN1, a gene that is regulated by a microRNA in zebrafish. FIN1 is normally expressed only in the dorsal fin. You’ve isolated a DOMINANT FIN1 mutant allele that results in ectopic (abnormal) FIN1 expression in the dorsal, caudal and pelvic fins. What is a likely explanation of the nature of the dominant mutant allele?
Group of answer choices
A. the dominant mutation inactivates an enhancer of FIN1
B. the dominant mutant allele is a deletion mutation that removes amino acid sequence in the FIN1 polypeptide where the microRNA normally binds
C. there is increased sensitivity to microRNAs that prevents normal splicing
D. the dominant mutant allele is a deletion mutation that removes sequence in the FIN1 mRNA that is homologous to the microRNA
E. the dominant mutant allele is an insertion mutation that introduces a sequence in the FIN1 mRNA that is homologous to the microRNA
microRNA regulates the translation of the mRNA
if the mRNA has a complementary sequence to mRNA the mRNA is degraded by the RISC if the mRNA is partially complementary to the mRNA the translation is inhibited.
microRNA regulates the expression of the FIN1 such that is expressed only in the dorsal fin, the mutation dominant FIN1, can not be regulated by the mRNA because it has no complementary sequence to the mRNA so the answer is
D. the dominant mutant allele is a deletion mutation that removes sequence in the FIN1 mRNA that is homologous to the microRNA
You are studying FIN1, a gene that is regulated by a microRNA in zebrafish. FIN1 is...
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