BIO1011 Week 9 Vocabulary Flashcards

Flashcards for reviewing key vocabulary from the BIO1011 Week 9 lecture on 'Coding Life: Reading The Instructions Of The Cell'.

Intron

A nucleotide sequence within a gene that is removed by RNA splicing while the final mature RNA product of a gene is being generated.

Messenger RNA (mRNA)

mRNA is a type of RNA that carries the genetic code from DNA in the nucleus to ribosomes in the cytoplasm.

It is produced during transcription, where RNA polymerase synthesizes an mRNA strand complementary to the DNA template. mRNA contains codons, which are sequences of three nucleotides that specify particular amino acids.

During translation, ribosomes read the mRNA sequence and use it to assemble a protein by matching each codon to its corresponding tRNA molecule carrying the appropriate amino acid. mRNA is essential for protein synthesis, as it provides the template for ribosomes to create proteins with the correct amino acid sequence.

Mutation

A change in the nucleotide sequence of a gene or DNA molecule.

Nucleotide

A building block of DNA or RNA, consisting of a nucleobase (adenine, guanine, cytosine, thymine, or uracil), a sugar molecule, and a phosphate group.

Operon

A cluster of genes transcribed as a single mRNA molecule, common in prokaryotes.

An operon typically includes a promoter, which is the DNA sequence where RNA polymerase binds to initiate transcription, an operator, which is a regulatory sequence that controls access of RNA polymerase to the promoter, and one or more structural genes that encode proteins.

Poly-A tail

The tail added to the 3' end of a pre-mRNA molecule.

Ploycistronic mRNA

An mRNA molecule that encodes multiple proteins, common in prokaryotes.

Primary transcript

The initial RNA molecule synthesized from a DNA template before processing.

Promoter

A DNA sequence where RNA polymerase binds to initiate transcription.

RNA polymerase

An enzyme that synthesizes RNA from a DNA template.

RNA splicing

The process of removing introns and joining exons to produce a mature mRNA molecule.

Spliceosome

A complex of proteins and RNA that splices pre-mRNA in eukaryotic cells.

TATA Box

A DNA sequence that controls gene expression.

Transcription

The process of synthesizing RNA from a DNA template.

It involves RNA polymerase binding to a promoter region on the DNA and using the DNA sequence as a template to create a complementary RNA molecule.

This process is essential for gene expression, as it allows the genetic information encoded in DNA to be converted into a form that can be used to direct protein synthesis. Transcription occurs in three main stages: initiation, elongation, and termination. In initiation, RNA polymerase binds to the promoter and unwinds the DNA.

In elongation, RNA polymerase moves along the DNA template, adding RNA nucleotides to the growing RNA molecule. In termination, RNA polymerase reaches a termination

Transcription Factor

A protein that binds to specific DNA sequences, thereby controlling the rate of transcription of genetic information from DNA to messenger RNA.

Transcription initiation complex

A complex of proteins including transcription factors, RNA polymerase, and other factors, that is required to initiate transcription.

Inducible gene expression

Gene expression that is activated by the presence of an inducer.

Inducible operon

An operon whose expression is increased in the presence of a particular substance, usually a substrate of the enzyme(s) encoded by the operon

Repressible operon

An operon under negative control. It is normally transcribed, but transcription is blocked when a repressor protein binds to the operator

Activator protein

A protein that binds to DNA and increases gene transcription

Repressor protein

A protein that binds to DNA and inhibits gene transcription.

Regulatory transcription factors

Regulatory proteins that bind to DNA sequences and affect the transcription of specific genes

Enhancers

DNA sequences that enhance transcription.

General transcription factors

Proteins, also known as basal transcription factors, that are required for RNA polymerase to bind to a promoter site and initiate transcription

positive / negative transcriptional regulation

Transcriptional regulation may be under either positive or negative control.

RNA base pair

The genetic code that uses three-base code words (codons) to specify particular amino acids.

combinatorial transcriptional regulation

Where the binding of one protein is dependent on the binding of another.

operator

A regulatory sequence located downstream from (i.e., 3' to) the start of a gene.

constitutive gene expression

Continuous transcription of a gene.

CRP-cAMP complex

Cyclic AMP receptor protein

RNA synthesis

The synthesis of RNA using DNA as a template.

Gene expression

Gene expression the process by which information from a gene is used in the synthesis of a functional gene product.