DNA, RNA, and Protein Conventions Flashcards Preview

GN 421 > DNA, RNA, and Protein Conventions > Flashcards

Flashcards in DNA, RNA, and Protein Conventions Deck (14):
1

Equivalent and Antiparallel

- Equivalent - no logical way to distinguish the two strands based on physical properties
- Antiparallel - the strands have an antiparallel arrangement
- 5' - 3' - strand on top
- 3' - 5'

2

Both Strands Can Contain Genes

- both strands can contain "genes" and be transcribed but in different directions.
- The top strand is the coding strand for gene 1. The bottom strand is the coding strand for gene 2.
- Often, when genome sequences are concerned, the sequence of only one strand is given.

3

The Two-Strand Convention

- The coding strand 5'-3' on the top
- the template strand 3'-5' on the bottom.

4

coding strand

- has the same "sense" (direction and sequence) as the mRNA that it codes for.
- exception of U in RNA and deoxyT in DNA
- it is called the sense strand or the gene.

5

template strand

- the strand that basepairs with the incoming nucleotides that are connected by phosphodiester linkage to form RNA in the process of transcription.
- it is complementary to the mRNA
- It is also code the non-coding strand, or the anti-sense strand or non-sense strand.

6

Transcription/RNA polymerase

- template is read 3'-5'.
- mRNA is synthesized 5'-3'.
- Therefore has the same "sense" as the gene or coding strand.

7

Translation/Ribosomes

- mRNA read 5'-3'
- protein synthesized N-terminal - C-terminal
- using these conventions, gene, mRNA, and protein all have the same "sense"

8

Go from coding strand to mRNA

- without flipping
- just switch T's to U's

9

nucleic acids versus proteins

- nucleic acids have 5' to 3' ends
- proteins have amino and carboxy termini

10

The way usually seen

5' gene or coding strand 3'
3' template strand 5'
I
transcription V

5' mRNA 3'
I
V
+H3N Protein COO-

11

Making cDNA

- sequence of the cDNA same as gene.
- ALWAYS TALKS ABOUT SEQUENCE OF SECOND STRAND
- most time cDNA made double stranded so we can easily clone and sequence them
- reverse transcriptase requires polyDT as a primer
- RNA sensitive to high pH so remove and degrade with NaOH
- remove loop with single-stranded nucleotides

12

capital blue

exons translated

13

capital black

exons untranslated

14

lowercase blue

introns.