Question

please explain!! thank you!

EE Calibri (Body)11 AA AA B I U . X, X? A .A . 2 . + . habeat code AaBBCCDC Normal No Spacing Heading! 2 3 . The basis for molecular regulation of gene expression is through base-pairing of complementary he sequences that are targeted are those that are critical in initiating translation (such as the Shine Dalgarno sequence and initiation codon of an mRNA). Base-pairing at these key regions blocks access of ribosomes, and in this case, translation initiation would be prevented. To help you understand this base-pairing mechanism, let's start with a sequence of a made up regulatory RNA. 5'- AGCCAUCGGUAUCGACCUCCUGG-3' The goal here is for you to determine which of the mRNA sequences listed below, could be regulated by our made up regulatory RNA. Specifically, we are focusing on regulation in terms of inhibiting translation initiation. To answer this fully, you'll have to recall the rules of base-pairing that we have discussed many times in class! You must indicate which RNA you believe to be regulated (1pt), and then give a description as to why you came to this conclusion (2pts). a) 3'- UTGCTGUUCGGTCCTCCUGCTUTGGCTUCCGUTCGUTGUTCGTUGCGGGUTUTTTTCCC...-5' b) 5'- CCCTTTTUTUGGGCGUTGCTUGTUGCTUGCCUTCGGTUTCGUCCTCCTGGCUUGTCGTU...-3' c) 5'- UACGACUUGCCAGGAGGUCGAUACCGAUGGCUAGCUACUAGCAUCGCCCUAUAAAAGGG...-3' d) 5'- GGGAAAAUAUCCCGCUACGAUCAUCGAUCGGUAGCCAUAGCUGGAGGACCGUUCAGCAU...-3' e) 3'- UACGACUUGCCACGUGGUCGAUACCGAUAGCUAGCUACUAGCAUCGCCCUAUAAAAGGG...-5'

Answer 1

First of all, we have to make the regulatory m RNA sequence is into 3' to 5' direction.

Then we know that pairing occurs in anti parallel manner. And look for the pairing between mRNA and regulatory mRNA.

Now look in the image:

3GGUCCUCCAGOUAUGGCUACOGAS c) 5'- UACGACUU CCAGGAGGUCGAUACCGAUGGCUACUACUAGCAUCGCCCUAUAAAAGGG...-3'

This complementary sequence knhibits the binding of ribosomes to the mRNA.

That's why answer is C.