Another way to study the role of proteins (e.g., transcription factors) that function in development is to microinject the mRNA that encodes a protein, or the purified protein itself, into an oocyte or embryo, and then determine how this affects the subsequent development of the embryo, larva, and adult. For example, if Bicoid protein is injected into the posterior region of an oocyte, the resulting embryo will develop into a larva that has anterior structures at both ends. Based on your understanding of the function of each developmental gene, what would be the predicted
A. Nanos mRNA injected into the anterior end of an oocyte
B. Antp protein injected into the posterior end of an embryo
C. Toll mRNA injected into the dorsal side of an early embryo
Want to see the full answer?
Check out a sample textbook solutionChapter 26 Solutions
Genetics: Analysis and Principles
- Protein levels and mRNA levels for a particualr gene don’t always match. For example, the GCN4 gene in yeast is always producing mRNA, but the Gcn4 protein is only made when the cells are starved. B. What does this mean for diagnostic techniques that try to look at gene expression?arrow_forwardWhen doing a lab that involves Extraction of Genomic DNA from adult Drosophila melanogaster. - What are the controls you should use and why use these? What is special about the genomic DNA? What do you expect to find (using these genomic DNA samples)? please help!arrow_forwardYou found a strain of mutant fruit flies (Drosophila) living on the rotten bananas in your dorm room. You notice that many of the larvae have abnormal abdominal segments. You want to know if the “abdomenless” mutation is a maternal effect gene. Describe an experiment you would do to determine this, and the results that would support and contradict the notion that the abdomenless gene encodes a maternal determinant.arrow_forward
- Which of the following statements about Tbx5 is true? a. Tbx5, Tbx4, and AmphiTbx4/5 have very similar coding regions. b. Tbx5 is involved in tail development in vertebrates. c. Tbx5, Tbx4, and AmphiTbx4/5 have very similar regulatory regions. d. Tbx5 initiates hindlimb development.arrow_forwardWhat is the purpose of syncytin, the protein product of sequences originally added to the human genome from a retrovirus, as it relates to early fetal development in human reproduction?arrow_forwardgiven a situation in which you manipulated a zebrafish embryo by injecting high levels of retinoic acid so that no anterior genes will be expressed. Surprisingly, after embryonic development, you are still able to observed the presence of anterior structures. What could explain this observation? What changes in your experiment would you make to achieve your objective?arrow_forward
- In recent years, techniques have been developed to clone mammals through a process called nuclear transfer, in which the nucleus of a somatic cell is transferred to an egg cell from which the nuclear material has been removed . Research has demonstrated that when a nucleus from a differentiated somatic cell is transferred to an eggcell, only a small percentage of the resulting embryos complete development, and many of those that do die shortly after birth. In contrast, when a nucleus from an undifferentiated embryonic stem cell is transferred to an egg cell, the percentage of embryos that complete development is significantly higher (W. M. Rideout, K. Eggan, and R. Jaenisch. 2001. Science 293:1095–1098). Propose a possible reason for why a higher percentage of cloned embryos develop successfully when the nucleus transferred comes from an undifferentiated embryonic stem cell.arrow_forwardBy whole-exome sequencing, you have identified an early termination mutation in KLHL4 in a human patient with an undiagnosed blood vessel anomaly. There is almost nothing known about the function of this gene, and no existing animal models! To begin to understand its function, you decide to use the zebrafish model. You first want to know where in the embryo this gene is expressed. Which technique would you use to identify the cell type that expresses klhl4 mRNA in zebrafish embryos? You find that this gene is expressed in endothelial cells, which line blood vessels. Intrigued by this finding, you next decide to disrupt the gene in zebrafish using CRISPR/Cas9. The DNA sequence that you want to target is below. What is the sequence of your 20-base guide RNA? 5’ TAGCAATTATGCGCGCTAGCAATTGCGTAGGTCATAATGCAGCTGAC 3’ 3’ ATCGTTAATACGCGCGATCGTTAACGCATCCAGTATTACGTCGACTG 5’ After injecting the gRNA with Cas9, what are potential outcomes? Enter true or false.…arrow_forwardA mouse gene was identified and determined to be required for formation of heart muscle. A gene with a similar sequence was identified in the human genome. What experiment could scientists do to determine if the mouse and human genes have similar functions? A. The scientist could place the normal human gene into normal mice and see if the resulting mice are viable. B. The scientist could search the human genome for genes that encode proteins that are identical to the protein encoded by the mouse gene. C. The scientist could place the normal human gene into mutant mice to see if heart muscle forms in the mouse. D. The scientist could place the mutant mouse gene into humans to see if humans develop without heart muscle.arrow_forward
- In flies, the gap gene kruppel is expressed in a broad band in the middle of the embryo with giant expressed as its anterior border and knirps at its posterior border. How is the expression of kruppel limited to this band in the embryo? Describe the spatial regulation of the kruppel gene.arrow_forwardHow have we discovered that specific genes control development in an organism like Drosophila?arrow_forwardYou observe that a particular gene is being transcribed during development. How can you tell whether the expression of this gene is under transcriptional or translational control?arrow_forward
- Biology (MindTap Course List)BiologyISBN:9781337392938Author:Eldra Solomon, Charles Martin, Diana W. Martin, Linda R. BergPublisher:Cengage Learning