Establishment of Beginning of the lytic pathway the lysogenic state cro protein inhibits transcription from PL and PRM- cro protein also inhibits PR. but only after transcription of the 10, P, and O genes has occurred. cll activates transcription from Pand PRE- cll ll cro int xis cll N cl cго cllo P о int xis clll NV cl cro cll O P Q Pi PR PRE OR tRI OL Рем tr2 PR PRE OR tRI OL Рем t PL ti PL tp2 Maintenance of cl (the à repressor) inhibits the lysogenic state P and PR but activates PRM- -a repressor Activates PRM Expression of phage genes shown in tan in Figure 18.7 leads to the synthesis of new phages and bacterial cell lysis. Inhibits P Inhibits PR int xis cll NV c/ cro cll O P Q Pi PR PRE tr2 OL OR tRI PRM (a) Lysogenic cycle (b) Lytic cycle FIGURE 18.10 Phage 2 gene regulation during the lysogenic and lytic cycles. (a) Gene regulation pattern that leads to the lysogenic cycle. (b) Steps that lead to the lytic cycle.

Establishment of Beginning of the lytic pathway the lysogenic state cro protein inhibits transcription from PL and PRM- cro protein also inhibits PR. but only after transcription of the 10, P, and O genes has occurred. cll activates transcription from Pand PRE- cll ll cro int xis cll N cl cго cllo P о int xis clll NV cl cro cll O P Q Pi PR PRE OR tRI OL Рем tr2 PR PRE OR tRI OL Рем t PL ti PL tp2 Maintenance of cl (the à repressor) inhibits the lysogenic state P and PR but activates PRM- -a repressor Activates PRM Expression of phage genes shown in tan in Figure 18.7 leads to the synthesis of new phages and bacterial cell lysis. Inhibits P Inhibits PR int xis cll NV c/ cro cll O P Q Pi PR PRE tr2 OL OR tRI PRM (a) Lysogenic cycle (b) Lytic cycle FIGURE 18.10 Phage 2 gene regulation during the lysogenic and lytic cycles. (a) Gene regulation pattern that leads to the lysogenic cycle. (b) Steps that lead to the lytic cycle.

Biology Today and Tomorrow without Physiology (MindTap Course List)

5th Edition

ISBN:9781305117396

Author:Cecie Starr, Christine Evers, Lisa Starr

Publisher:Cecie Starr, Christine Evers, Lisa Starr

Chapter7: Gene Expression And Control

Section: Chapter Questions

Problem 15SQ

See similar textbooks

Similar questions

. In an effort to determine the location of an operator sitefor a negatively regulated gene, you have made a seriesof deletions within the regulatory region. The extent ofeach deletion is shown by the line underneath the sequence, and the resulting expression from the operon(i = inducible; c = constitutive; − = no expression) isalso indicated.... GGAT C T T AGCCGGCTAACATGATAAATATAA......C C T AGAATCGGCCGA TTGTA C T A TTT ATAT T ...1 i2 –3 c4 –5 ca. What can you conclude from these data about thelocation of the operator site?b. Why do you think deletions 2 and 4 show no expression of the gene?
Certain hormones, such as epinephrine, can increase the levels ofcAMP within cells. Let’s suppose you pretreat cells with or withoutepinephrine and then prepare a cell extract that contains theCREB protein.You then use an electrophoretic mobility shift assay to analyzethe ability of the CREB protein to bind to a DNA fragmentcontaining a cAMP response element (CRE). Describe what theexpected results would be.
A pre-initation complex (PIC) is required for transcription to begin. State which TFII protein has catalytic function.
Suppose that you have cancer cell line X was treated with drug Y toincrease the expression levels of protein Z which is a tumorsuppressor gene. (no need for this qustion)Explain How can you study protein Z in these cells? (needed)
Define the following terms:a. Crabtree effectb. transcription factorc. response elementd. insuline. malate shuttle
Draw the mature mRNA molecule (ready fir transport to the cytoplasm) with modifications required fir export. Label all modifications required gor export.
What factors called mitogens stim-ulate cultured mammalian cells to proliferate by inducing expression of early response genes. Many of these genesencode transcription factors that stimulate expression ofgenes encoding the G1/S phase cyclins and E2F transcriptionfactors.
Repressors bind toa) Promoterb) Enhancerc) Operatord) Hormone response element
Create a metabolism cocept map using these terms RepressorInducer RiboswitchRepression InductionPositive regulationActivatorOperator Heat shocklac operontrp operon Catabolite RepressionHeat shocksigma-32 Negative regulationTwo-component regulationSensor Kinase Autoinducing Peptide (AIP)Response regulatorSigma factorsFeedback inhibitionProtein StabilityQuorum SensingRNA regulationAntisense RNAHomoserine Lactone (AHL)
Repressor molecules bind toa) Operatorb) Promoterc) Enhancerd) Hormone response element
Scientists have exploited the siRNA pathway toperform a technique called RNA interference—ameans to knock down the expression of a specificgene without having to make mutations in it. Theidea is to introduce dsRNA corresponding to thetarget gene into an organism; the dsRNA is thenprocessed into an siRNA that leads to the degradation of the target gene’s mRNA. One clever methodfor delivery of the dsRNA to some organisms (thenematode C. elegans, for example) is to feed thembacteria transformed with a recombinant plasmidthat expresses dsRNA.a. Draw a gene construct that, when expressed from aplasmid in bacteria, could be used to knock downby RNA interference the expression of gene X ofC. elegans.b. How can you test if gene X expression is obliterated in worms that have eaten the bacteria transformed with a plasmid containing your construct?c. Do you think that only gene X expression will beaffected in these worms? Explain.
You have isolated a protein that binds to DNA in theregion upstream of the promoter sequence of the sysgene. If this protein is a positive regulator, which ofthe following would be true?a. Loss-of-function mutations in the gene encodingthe DNA-binding protein would cause constitutiveexpression of sys.b. Loss-of-function mutations in the gene encodingthe DNA-binding protein would result in little orno expression of sys.