Chp 16 Connect

How many Barr bodies would you expect to find in a cell from a person with the following genotype? XO

0

How many Barr bodies would you expect to find in a cell from a person with the following genotype? XY

0

How many Barr bodies would you expect to find in a cell from a person with the following genotype? XYY

0

How many Barr bodies would you expect to find in a cell from a person with the following genotype? XX

1

How many Barr bodies would you expect to find in a cell from a person with the following genotype? XXY

1

How many Barr bodies would you expect to find in a cell from a person with the following genotype? XXX

2

How many Barr bodies would you expect to find in a cell from a person with the following genotype? XXXY

2

You have available a dwarf male mouse with the genotype Igf-2m/Igf-2m and a dwarf female with the genotype Igf-2m/Igf-2. What is the minimum number of generations it would take to produce a normal male? Hint: mice inbreed happily.

2

Covalent addition to histone Change

Acetylation, Phosphorylation, Methylation

The inactive X chromosome in a human female somatic cell is called a ___

Barr body.

The symmetry break that occurs is due to localization of___ to one X chromosome.

CTCFs

Chromatin Remodeling Cis or Trans

Cis

Covalent Addition to DNA Cis or Trans

Cis

Covalent addition to histone Cis or Trans

Cis

Location of histone varient cis or trans

Cis

Can be the result of a transcription factor

Cis epigenetic mechanism

DNA Methylation

Cis epigenetic mechanism

X chromosome inactivation

Cis epigenetic mechanism

Cell type differentiation

Developmental

DNA Methylation during oogenesis

Developmental

Xist and Tsix

Developmental

The Igf-2 locus encodes a growth hormone called insulin-like growth factor 2. Igf-2 is an imprinted gene. The copy of the gene inherited from the father is active and the copy inherited from the mother is silenced. Igf-2 is the wild type allele. There is also a recessive allele Igf-2- The expression of the Igf-2- allele results in dwarf offspring. Two crosses are listed below. Match the cross with the expected phenotype of the offspring. 2. An Igf-2 Igf-2 female crossed with an Igf-2- Igf-2- male

Dwarf offspring

DNA Covalently modified by toxins

Environmental

Diet of Royal jelly creates queen bees

Environmental

Temperature causes histone modifications

Environmental

Coat color in mice is controlled only by dietary factors

F

Coat color in mice is only controlled by methylation of a promoter

F

Exposure of pregnant female mice to a specific diet will result in all progeny being pseudo-agouti phenotype

F

Location of histone varient change

Histone varients localized to specific locations

Which of the following is a mechanism to imprint genes?

Methylation of cytosine

Covalent Addition to DNA Change

Methylation on C

The Igf-2 locus encodes a growth hormone called insulin-like growth factor 2. Igf-2 is an imprinted gene. The copy of the gene inherited from the father is active and the copy inherited from the mother is silenced. Igf-2 is the wild type allele. There is also a recessive allele Igf-2- The expression of the Igf-2- allele results in dwarf offspring. Two crosses are listed below. Match the cross with the expected phenotype of the offspring. An Igf-2- Igf-2- female crossed with an Igf-2 Igf-2 male

Normal offspring

Chromatin Remodeling Change

Nucleosomes moved to new location

ORDER PRC2 catalyzes trimethylation Recruitment of PRC1 inhibits transcription through compaction, further modifcation of histones and interaction with transcription factors Trimethylation of Lysine 27 may directly inhibit transcription and recruit PRC1 PRE binding protein binds to PRE and recruits PRC2 to the site

PRE binding protein binds to PRE and recruits PRC2 to the site PRC2 catalyzes trimethylation Trimethylation of Lysine 27 may directly inhibit transcription and recruit PRC1 Recruitment of PRC1 inhibits transcription through compaction, further modifcation of histones and interaction with transcription factors

ORDER Recruitment of PRC1 inhibits transcription through compaction, further modifcation of histones and interaction with transcription factors PRE binding protein binds to PRE and recruits PRC2 to the site PRC2 catylizes trimethylation Trimethylation of Lysine 27 may directly inhibit transcription and recruit PRC1

PRE binding protein binds to PRE and recruits PRC2 to the site PRC2 catylizes trimethylation Trimethylation of Lysine 27 may directly inhibit transcription and recruit PRC1 Recruitment of PRC1 inhibits transcription through compaction, further modifcation of histones and interaction with transcription factors

Coat color in mice can be correlated with the amount of methylation of a transposable element

T

If the transposable element is not upstream from the Agouti allele there should be no influence of diet on coat color

T

The methylation of a TE promoter may influence coat color

T

Two phenotypically normal mice produce a single F1 male progeny that is also phenotypically normal. This F1 male is mated with an lgf-2/lgf-2 female and ½ of the progeny are dwarf. Where did the lgf-2- allele in the F2 progeny originate?

The parental generation female that had to have been heterozygous (lgf-2/lgf-2-)

Feedback loop cis or trans

Trans

Cell fusion results in both cell's genes being transcriptionally repressed

Trans epigenetic mechanism

Cell fusion results in no chance in transcription of one cell's genes

Trans epigenetic mechanism

Feedback loop change

Transcription factor stimulates own production

The definition of epigenetics is the study of mechanisms of heritable traits that ___ the result of changes in DNA sequence.

are not

Methylation in the sperm occurs by a ___ methylase

de novo

The ____ may also be methylated

differentially methylated region (DMR)

In___ inheritance the transmission of the trait may be based not on the allele but on which parent the allele comes from.

epigenetic

The inheritance of traits is sometimes the direct result of specific alleles being present or absent, but it can also be due to the ability of an allele to be___.

expressed

Binding of the CTCF proteins results in the chromosome ____

forming a loop

Imprinting at the Igf-2 locus may be initiated by methylation at a region between the H19 and Igf2 locus known as the ___

imprinting control region (ICR)

Although the Tsix transcript is produced by both X chromosomes the Xist transcript is only produced from the___ chromosome.

inactive

Presence of the xist transcript on the Xi chromosome results in the recruitment of___.

macroH2A

The active Igf-2 allele is inherited from the____

male

At least some genes are silenced on inactive X chromosomes by___.

methylation

In epigenetics, change can be due to____ of DNA.

methylation

The modifications made to DNA in epigenetics results in changes in___ association with the DNA.

protein

The selection of which chromosome is inactivated is a__ process.

random

Methylation of the sites around the Igf2 locus____ binding of the CTC binding factors

suppresses

The body size of a mouse can be controlled by the expression of the Igf-2 gene which can be regulated by imprinting. A dwarf female mouse is heterozygous for the lgf-2 gene (lgf-2/lgf-2-). You can conclude that

the lgf-2- allele came from the father.