AP Bio Unit 6 part 2

antibiotic resistance

ability of an organism to be unaffected by the actions of an antibiotic

chain termination method

method of DNA sequencing using labeled dideoxynucleotides to terminate DNA replication; it is also called the dideoxy method or the Sanger method

clone

exact replica

DNA microarray

method used to detect gene expression by analyzing an array of DNA fragments that are fixed to a glass slide or a silicon chip to identify active genes and identify sequences

foreign DNA

DNA that belongs to a different species or DNA that is artificially synthesized

gel electrophoresis

technique used to separate molecules on the basis of size using electric charge

gene targeting

method for altering the sequence of a specific gene by introducing the modified version on a vector

gene therapy

technique used to cure inheritable diseases by replacing mutant genes with good genes

genetic marker

gene or sequence on a chromosome with a known location that is associated with a specific trait

genetic recombination

exchange of DNA between homologous pairs of chromosomes

genetically modified organism (GMO)

organism whose genome has been artificially changed

genome mapping

process of finding the location of genes on each chromosome

genomics

study of entire genomes including the complete set of genes

host DNA

DNA that is present in the genome of the organism of interest

linkage analysis

procedure that analyzes the recombination of genes to determine if they are linked

northern blotting

transfer of RNA from a gel to a nylon membrane

polygenic

phenotypic characteristic caused by two or more genes

polymerase chain reaction (PCR)

technique used to amplify DNA

recombinant DNA

combination of DNA fragments generated by molecular cloning that does not exist in nature; also known as a chimeric molecule

recombinant protein

protein product of a gene derived by molecular cloning

shotgun sequencing

method used to sequence multiple DNA fragments to generate the sequence of a large piece of DNA

Southern blotting

transfer of DNA from a gel to a nylon membrane

Ti plasmid

plasmid system derived from Agrobacterium tumifaciens that has been used by scientists to introduce foreign DNA into plant cells

transgenic

organism that receives DNA from a different species

5' cap

a methylated guanosine triphosphate (GTP) molecule that is attached to the 5' end of a messenger RNA to protect the end from degradation

activator

protein that binds to prokaryotic operators to increase transcription

catabolite activator protein (CAP)

protein that complexes with cAMP to bind to the promoter sequences of operons that control sugar processing when glucose is not available

DNA methylation

epigenetic modification that leads to gene silencing; commonly found in cancer cells

enhancer

segment of DNA that is upstream

epigenetic

heritable changes that do not involve changes in the DNA sequence

eukaryotic initiation factor-2 (eIF-2)

protein that binds first to an mRNA to initiate translation

gene expression

processes that control the turning on or turning off of a gene

histone acetylation

epigenetic modification that leads to gene expression; commonly found in cancer cells.

inducer

a small molecule that either activates or represses transcription

inducible operon

operon that can be activated or repressed depending on cellular needs and the surrounding environment

initiation complex

protein complex containing eIF2-2 that starts translation

lac operon

operon in prokaryotic cells that encodes genes required for processing and intake of lactose

microRNA (miRNA)

small RNA molecules (approximately 21 nucleotides in length) that bind to RNA molecules to degrade them

negative regulator

protein that prevents transcription

operator

region of DNA outside of the promoter region that binds activators or repressors that control gene expression in prokaryotic cells

operon

collection of genes involved in a pathway that are transcribed together as a single mRNA in prokaryotic cells

poly-A tail

a series of adenine nucleotides that are attached to the 3' end of an mRNA to protect the end from degradation

positive regulator

protein that increases transcription

post-transcriptional

control of gene expression after the RNA molecule has been created but before it is translated into protein

post-translational

control of gene expression after a protein has been created

repressor

protein that binds to the operator of prokaryotic genes to prevent transcription

transcription factor

protein that binds to the DNA at the promoter or enhancer region and that influences transcription of a gene

trp operon

series of genes necessary to synthesize tryptophan in prokaryotic cells

tryptophan

amino acid that can be synthesized by prokaryotic cells when necessary