BLG 307 RNA Structures and Transcription

Practice flashcards to review key concepts related to RNA structures and transcription as covered in BLG 307 lecture notes.

What type of RNA is produced as a messenger for protein synthesis?

mRNA (messenger RNA)

Which RNA polymerase is responsible for the transcription of mRNA in eukaryotes?

RNA polymerase II

What are the three main types of RNA produced in all cells?

rRNA, tRNA, and mRNA.

What is the role of sigma factors in bacterial transcription?

Sigma factors aid in promoter recognition to initiate transcription.

What is the function of introns in eukaryotic genes?

Introns are non-coding sequences that must be spliced out from pre-mRNA to form mature mRNA.

What process modifies the 5' end of eukaryotic mRNA?

5' capping.

What does polyadenylation refer to in the context of mRNA processing?

The addition of a poly A tail to the 3' end of mRNA.

What is the main difference in transcription between prokaryotes and eukaryotes?

Prokaryotes have a single RNA polymerase, while eukaryotes have three different RNA polymerases.

What are the two types of termination in bacterial transcription?

Rho-independent (intrinsic) and Rho-dependent termination.

What happens during the elongation phase of transcription?

RNA polymerase synthesizes RNA by adding nucleotides to the growing RNA chain.

Why is it important for eukaryotic cells to have complex RNA processing steps?

To ensure proper mRNA maturation and regulate gene expression.

What is the significance of the Pribnow box in bacterial promoters?

It's a conserved sequence in bacterial promoters crucial for transcription initiation.

What molecular event occurs at transcription termination for Rho-dependent mechanisms?

Rho helicase binds and unwinds RNA from the DNA template, resulting in RNA release.

How do eukaryotic RNA polymerases differ in their transcription products?

Pol I transcribes rRNAs, Pol II transcribes mRNAs and some small RNAs, Pol III transcribes tRNAs and 5S rRNA.

What mutational analysis technique is used to understand promoter function?

Analysis of transcription reporter genes to assess changes in gene expression.

What does the term 'abortive initiation' refer to during transcription?

The process where short RNA transcripts are repeatedly synthesized and released before elongation proceeds.