Week 8 - Genomes Flashcards
Central Dogma
The flow of genetic information in a cell: DNA → RNA → Protein. DNA is transcribed into RNA, which is then translated into protein.
cDNA (complementary DNA)
DNA synthesized from an mRNA template using reverse transcriptase. Used to study gene expression or clone eukaryotic genes.
Reverse Transcriptase
An enzyme that synthesizes DNA from an RNA template (used by retroviruses and in molecular biology labs to make cDNA).
Genome Sequencing
Determining the complete DNA sequence of an organism’s genome.
Dideoxy Nucleotide
Modified nucleotides used in Sanger sequencing that stop DNA strand elongation because they lack a 3’ OH group.
Sequence Reads
Short DNA fragments sequenced during genome sequencing. They must be assembled to reconstruct the full genome.
Scarffold
A series of overlapping sequence reads that are joined together during genome assembly.
Concatenate
To link together all scaffolds to make one long, continuous genome sequence.
Genome Annotation
The process of identifying genes, coding regions, and regulatory elements in a genome sequence.
Repeats
DNA sequences that occur multiple times in the genome (e.g., satellite DNA, transposons).
Single Copy Genes
Genes that are present only once in the genome.
Coding
Regions of DNA that code for proteins (exons).
Noncoding
DNA regions that do not code for proteins but may have regulatory or structural roles.
Regulatory Sequence
Segments of DNA that control gene expression, such as promoters and enhancers.
Promoter
A DNA sequence upstream of a gene that acts as the binding site for RNA polymerase to start transcription.
Enhancer
A regulatory DNA sequence that increases the transcription of a gene; can be located far from the gene it regulates.
Open Reading Frame (ORF)
A stretch of DNA with a start codon, stop codon, and potential to be translated into a protein.
PCR (Polymerase Chain Reaction)
A technique used to amplify specific DNA sequences millions of times in vitro.
Primers
Short DNA sequences that provide a starting point for DNA synthesis during PCR.
Heat
Used in PCR to denature the DNA, separating it into single strands.
TAQ Polymerase
A heat-stable enzyme from Thermus aquaticus used in PCR to synthesize new DNA strands.
Anneal = Basepair
The step in PCR where primers bind (basepair) to the target DNA sequence after cooling.
Plasmid
A small, circular DNA molecule found in bacteria that can be used as a vector for gene cloning.
Antibiotic Selection
A method to identify bacteria that have taken up a plasmid by growing them in the presence of an antibiotic.
Cloning
The process of making identical copies of DNA, cells, or organisms. In molecular biology, it refers to copying DNA into a vector like a plasmid.
Restriction Enzymes
Enzymes that cut DNA at specific sequences. Used in cloning to insert or remove DNA fragments.
