Genetics summary – VU BMS 2020/2021
Simone Zweers
Reference: Brooker, Genetics: Analysis and prinicples, 7 th edition
Chapter 12: Gene transcription and RNA modification
1
, Genetics summary – VU BMS 2020/2021
Simone Zweers
Reference: Brooker, Genetics: Analysis and prinicples, 7 th edition
- Gene = a segment of DNA that is used to make a
functional product
- Transcription = the process of synthesizing RNA
from a DNA template
- DNA replication provides a mechanism for copying
the information, so it can be transmitted
- Protein-encoding (structural) genes carry
information for the amino acid sequence of a
polypeptide
o Transcribed mRNA
o Translation sequence of nucleotides
determines the sequence of amino acids in a
polypeptide
- Central dogma of genetics: see image above, by
Crick.
12.1: Overview of transcription
Gene expression requires base sequences that perform different functional roles
- Gene expression = the process by which the information within a gene is used to produce a
functional product (polypeptide)
- Promotor
o a base sequence used
during transcription
o Provides a site for beginning
transcription
- Terminator
o A base sequence used
during transcription
o Specifies the end of
transcription
- DNA transcribed into RNA from
promotor to terminator
- RNA sequence complementary to
template strand
- Nontemplate strand = coding/sense
strand
- Transcription factors = proteins
that control the rate of transcription
o Some bind to promoter transcription
o Some recognize regulatory sequences (elements), short stretches of DNA involved in
the regulation of transcription
o Some inhibit transcription
- mRNA in bacteria: ribosome-binding site (Shine-Dalgarno sequence) = short sequence that
provides location for ribosome to bind and begin translation (complementary to a sequence in
ribosomal RNA
- mRNA contains a series of codons = groups of three nucleotides information for polypeptide’s
sequence
- start codon = first codon, close to ribosome binding site = AUG
- stop codon = last codon, signals the end of the translation = UAG – UAA – UGA
2
Simone Zweers
Reference: Brooker, Genetics: Analysis and prinicples, 7 th edition
Chapter 12: Gene transcription and RNA modification
1
, Genetics summary – VU BMS 2020/2021
Simone Zweers
Reference: Brooker, Genetics: Analysis and prinicples, 7 th edition
- Gene = a segment of DNA that is used to make a
functional product
- Transcription = the process of synthesizing RNA
from a DNA template
- DNA replication provides a mechanism for copying
the information, so it can be transmitted
- Protein-encoding (structural) genes carry
information for the amino acid sequence of a
polypeptide
o Transcribed mRNA
o Translation sequence of nucleotides
determines the sequence of amino acids in a
polypeptide
- Central dogma of genetics: see image above, by
Crick.
12.1: Overview of transcription
Gene expression requires base sequences that perform different functional roles
- Gene expression = the process by which the information within a gene is used to produce a
functional product (polypeptide)
- Promotor
o a base sequence used
during transcription
o Provides a site for beginning
transcription
- Terminator
o A base sequence used
during transcription
o Specifies the end of
transcription
- DNA transcribed into RNA from
promotor to terminator
- RNA sequence complementary to
template strand
- Nontemplate strand = coding/sense
strand
- Transcription factors = proteins
that control the rate of transcription
o Some bind to promoter transcription
o Some recognize regulatory sequences (elements), short stretches of DNA involved in
the regulation of transcription
o Some inhibit transcription
- mRNA in bacteria: ribosome-binding site (Shine-Dalgarno sequence) = short sequence that
provides location for ribosome to bind and begin translation (complementary to a sequence in
ribosomal RNA
- mRNA contains a series of codons = groups of three nucleotides information for polypeptide’s
sequence
- start codon = first codon, close to ribosome binding site = AUG
- stop codon = last codon, signals the end of the translation = UAG – UAA – UGA
2
