Chapter 18 - Regulation Of Gene Expression

Front 1

activator

Back 1

A protein that binds to DNA and stimulates gene transcription. In prokaryotes, activators bind in or near the promoter; in eukaryotes, activators bind to control elements in enhancers.

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alternative RNA splicing

Back 2

A type of eukaryotic gene regulation at the RNA-processing level in which different mRNA molecules are produced from the same primary transcript, depending on which RNA segments are treated as exons and which as introns.

Front 3

bicoid

Back 3

A maternal effect gene that codes for a protein responsible for specifying the anterior end in Drosophila.

Front 4

cell differentiation

Back 4

The structural and functional divergence of cells as they become specialized during a multicellular organism’s development. Cell differentiation depends on the control of gene expression.

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control element

Back 5

A segment of noncoding DNA that helps regulate transcription of a gene by binding a transcription factor. Multiple control elements are present in a eukaryotic gene’s enhancer.

Front 6

corepressor

Back 6

A small molecule that binds to a bacterial repressor protein and changes its shape, allowing it to switch an operon off.

Front 7

cyclic AMP (cAMP)

Back 7

Cyclic adenosine monophosphate, a ring-shaped molecule made from ATP that is a common intracellular signaling molecule (second messenger) in eukaryotic cells. It is also a regulator of some bacterial operons.

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cytoplasmic determinant

Back 8

A maternal substance, such as a protein or RNA, placed into an egg that influences the course of early development by regulating the expression of genes that affect the developmental fate of cells.

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determination

Back 9

The progressive restriction of developmental potential in which the possible fate of each cell becomes more limited as an embryo develops. At the end of determination, a cell is committed to its fate.

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differential gene expression

Back 10

The expression of different sets of genes by cells with the same genome.

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egg-polarity gene

Back 11

A gene that helps control the orientation (polarity) of the egg; also called a maternal effect gene.

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embryonic lethal

Back 12

A mutation with a phenotype leading to death of an embryo or larva.

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enhancer

Back 13

A segment of eukaryotic DNA containing multiple control elements, usually located far from the gene whose transcription it regulates.

Front 14

epigenetic inheritance

Back 14

Inheritance of traits transmitted by mechanisms not directly involving the nucleotide sequence of a genome.

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feedback inhibition

Back 15

A method of metabolic control in which the end product of a metabolic pathway acts as an inhibitor of an enzyme within that pathway.

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genomic imprinting

Back 16

A phenomenon in which expression of an allele in offspring depends on whether the allele is inherited from the male or female parent.

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histone

Back 17

A small protein with a high proportion of positively charged amino acids that binds to the negatively charged DNA and plays a key role in chromatin structure.

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histone acetylation

Back 18

The attachment of acetyl groups to certain amino acids of histone proteins.

Front 19

homeotic gene

Back 19

Any of the master regulatory genes that control placement and spatial organization of body parts in animals, plants, and fungi by controlling the developmental fate of groups of cells.

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inducer

Back 20

A specific small molecule that binds to a bacterial repressor protein and changes the repressor's shape so that it cannot bind to an operator, thus switching an operon on.