lec set 2

Question 1

What is genomic equivalence?

Answer 1

the theory that every cell of an organism carries the same genome

Question 2

What is differential gene expression?

Answer 2

1. every cell nucleus contains the complete genome and is a faithful copy of the genome that resulted from the union of male and female pronuclei at fertilization
2. genes that are not used are neither destroyed nor mutated
3. only a small percentage of the genome is expressed in each cell, and RNA synthesized in a particular cell is specific to the type of cell

Question 3

Definition: reporter genes

Answer 3

encoded products that can be easily detected and are not normally expressed in the cells being studied

Question 4

Definition: reported contracts

Answer 4

DNA from regions flanking a gene of interest (containing chancer sequences) are cloned into a construct containing a promoter sequence upstream of a reporter gene

Question 5

Definition: enhancer

Answer 5

DNA sequence that controls the efficiency and rate of transcription from a specific promoter

Question 6

Definition: transcription factors

Answer 6

bind to enhancer elements (DNA sequence) and may enhance or suppress the ability of RNApol to initiate transcription at nearby promoter

Question 7

Definition: alternative RNA splicing

Answer 7

differences in which introns are removed

Question 8

Definition: microRNA (miRNA)

Answer 8

another way cells regulate mRNA stability or the translation of mRNAs

Question 9

Definiton: Induction

Answer 9

the process by which one cell population influences the development of neighbouring cells via interactions at close range

Question 10

Definiton: paracrine factor

Answer 10

the signal produced by the inducer, usually a secreted protein

Question 11

Definition: inducer

Answer 11

the tissue the produces the signal(s) that change the cellular behaviour of the other tissue

Question 12

Definition: competence

Answer 12

the ability of cells or tissue to respond to a specific inductive signal

Question 13

Definitions: signal transduction

Answer 13

• receptors are transmembrane proteins
• when ligand (paracrine factor) binds they undergo a conformational change unusually activating a cytoplasmic domain of the receptor, usually kinase activity (commonly tyrosine kinase)

Question 14

What is the ultimate test for genomic equivalence

Answer 14

• nuclear transfer
• demonstrates that all cell types carry the same set of genes

Question 15

what are enhancer elements? and what is another commonly used term for enhancer?

Answer 15

• DNA sequences that increase the transcription of genes
• another term: cis- regulatory elements