Insulin Review Article Questions

1. In what journal did this article appear? When? Science, VOL 208 April 4, 1980
   
2. What is the primary purpose of this paper? To see if human DNA can be cloned or if theres similiarities between human DNA and other DNA containing organisms
   
3. What is the structural difference between insulin and proinsulin? Insulin: theres 2 polypeptide chains, Proinsulin: theres a larger polypeptide(preproinsulin) identified by invitro translation pf messenger(RNA)
   
4. What is complementary DNA (cDNA)? Total human insulinoma mRNA
   
5. What is meant by the "polyA tail" or "polyadenylation" of a gene? The A peptide most of amino acids, in receptor binding highest degree nucleotide and amino acid homology
   
6. What is meant by the statement that "insulin A and B chains are highly conserved"? The degree of homology of rat I, II and human amino acid sequences is matched by the overall nucleotide sequence homology
   
7. Which chain is most highly conserved? Chain A
   
8. What do the researchers believe is the purpose of the C chain? It helps the proinsulin molecule to assume its correct three-dimension conformation
   
9. Why does it make sense that the C chain is more variable (less highly conserved) than the A chain and B chain? C, binds them together and has no other function, it assists them
   
10. What do the researchers believe is the purpose of the pre-peptide (D chain)? Amino acid sequence in pre-peptide region must be important for insulin signal sequence activity
    
11. How does the human preproinsulin gene differ from rat preproinsulin (rat I and rat II)? The human preproinsulin mRNA extends 73 nucleotides beyond the translation termination codon, whereas both rat I and II mRNA 3' untranslated regions are about 20 nucleotides shorter.
    
12. What is the first codon in the coding region of the gene (at the start of the pre-peptide) and what is the first amino acid in the polypeptide? Adenylate, glutamic