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Transcription and RNA Processing
During transcription, RNA polymerase synthesizes RNA from a DNA template with the help of accessory proteins. In this tutorial, you will review the steps of transcription in eukaryotes and bacteria and investigate splicing of mRNAs in eukaryotes.
Part A - Transcription in bacteria
The diagram below shows a length of DNA containing a bacterial gene.
Drag the labels to their appropriate locations in the diagram to describe the function or characteristics of each part of the gene. Not all labels will be used.

You labeled 3 of 5 targets incorrectly. Keep in mind that the origin of replication is involved in the copying of DNA, which is a different process than the synthesis of RNA from a DNA template.



Part B - Transcription in eukaryotes
Drag the labels into the flowchart to show the order of events as they are thought to occur during eukaryotic transcription involving RNA polymerase II (RNA pol II).

Clueless

Part C - Pre-mRNA splicing in eukaryotes
The following eukaryotic structural gene contains two introns and three exons.
Eukaryotic structural gene with two introns and three exons
The table below shows four possible mRNA products of this gene. Use the labels to explain what may have caused each mRNA.
Drag the correct label to each location in the table. Labels may be used once, more than once, or not at all.

Attempted once, but still have a missing answer.

Extra information Chapter 9; The Molecular Biology of Translation
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Part C - Pre-mRNA splicing in eukaryotes
The following eukaryotic structural gene contains two introns and three exons.
Eukaryotic structural gene with two introns and three exons
The table below shows four possible mRNA products of this gene. Use the labels to explain what may have caused each mRNA.
Drag the correct label to each location in the table. Labels may be used once, more than once, or not at all.

Attempted once, but still have a missing answer.

1) A. mutations in splicing signal sequences in intron 2. Intron 2 is still included in the mature mRNA, but it should have been spliced out. For this to happen, there would have been some kind of mutation in the splicing signal for that intron.

2) D. mutation in the gene's promoter sequence. No mRNA was produced, so transcription didn't even occur. Because the promoter sequence is required to initiate transcription, a mutation would need to occur in it for no mRNA to be produced.

3) B. mutation in splicing signal sequences in both intron 1 and intron 2. Because both intron 1 and intron 2 were in the mature mRNA and not spliced out like they should have been, there was a problem with the splicing signal sequences for both introns.

4) C. no mutation in any splicing signal sequences. All of the introns were spliced out of the mature mRNA, so the proper mRNA was produced. Thus, there were no mutations in any of the splicing signal sequences.
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Got #1 right after the second try for anyone who needs it in the future

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Thanks for posting this guys, it was really helpful, because I was stuck on this problem
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Thank you for posting this, I was having a very hard time figuring it out even with the hints.
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Part-c


Correct

 Bacterial transcription is a four-stage process.

1. Promoter recognition: RNA polymerase is a holoenzyme composed of a five-subunit core enzyme and a sigma (σ ) subunit. Different types of σ  subunits aid in the recognition of different forms of bacterial promoters. The bacterial promoter is located immediately upstream of the starting point of transcription (identified as the +1 nucleotide of the gene). The promoter includes two short sequences, the –10 and –35 consensus sequences, which are recognized by the σ  subunit.
2. Chain initiation: The RNA polymerase holoenzyme first binds loosely to the promoter sequence and then binds tightly to it to form the closed promoter complex. An open promoter complex is formed once approximately 18 bp of DNA around the –10 consensus sequence are unwound. The holoenzyme then initiates RNA synthesis at the +1 nucleotide of the template strand.

3. Chain elongation: The RNA-coding region is the portion of the gene that is transcribed into RNA. RNA polymerase synthesizes RNA in the 5′ → 3′ direction as it moves along the template strand of DNA. The nucleotide sequence of the RNA transcript is complementary to that of the template strand and the same as that of the coding (nontemplate) strand, except that the transcript contains U instead of T.

4. Chain termination: Most bacterial genes have a pair of inverted repeats and a polyadenine sequence located downstream of the RNA-coding region. Transcription of the inverted repeats produces an RNA transcript that folds into a stem-loop structure. Transcription of the polyadenine sequence produces a poly-U sequence in the RNA transcript, which facilitates release of the transcript from the DNA.






 
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Thanks!
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ANSWER 2: Correct!

Transcription by RNA pol II in eukaryotes begins when TFIID recognizes and binds to the TATA box. The bound TFIID helps recruit TFIIB, TFIIF, and RNA pol II. Once those subunits of the minimal initiation complex are bound, TFIIE and TFIIH bind to form the complete initiation complex.
Assembly of the complete initiation complex releases RNA pol II, which begins synthesizing the RNA transcript in the 5′ → 3′ direction. After the first 20–30 nucleotides have been synthesized, a cap consisting of a methylated guanine is added to the 5′ end of the pre-mRNA.
Intron removal occurs as RNA pol II continues to elongate the pre-mRNA. When the polyadenylation signal has been transcribed, a poly-A tail is added to the 3′ end of the pre-mRNA. Polyadenylation is usually coupled with the termination of transcription.
Source Mastering Genetics
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 Dideoxynucleotide DNA sequencing
The diagram below shows an autoradiograph of a DNA sequencing gel.
Type the 5' to 3' sequence of the template strand (“inferred strand”) based on the pattern in this gel. Use only capital letters for the sequence.

Post Merge: A year ago

Dideoxynucleotide DNA sequencing
The diagram below shows an autoradiograph of a DNA sequencing gel.
Type the 5' to 3' sequence of the template strand (“inferred strand”) based on the pattern in this gel. Use only capital letters for the sequence.
Source mastering genetics
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This is the correct answer
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Thank You!! It was very helpful for me to understand the definitions. I kept mixing them up!!
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