4. To understand the function of the Bcl11a protein, scientists attempted to knockdown its expression by transfecting human cells in culture with siRNA targeting the Bcl11a gene. A. Briefly describe the first step of the pathway initiated by siRNA entering the cytoplasm. Following transfection of cells with two different siRNA sequences complementary to the Bcl11a gene (siRNA 1 and siRNA 2), the level of Bcl11a protein expression was measured by western blot. The researchers also included a positive control to measure actin, a housekeeping gene. In a western blot experiment*, how do scientists B. specifically detect a protein of interest on a nitrocellulose membrane? Control siRNA 1 siRNA 2 C. Which siRNA sequence was more effective at targeting Bcl11a expression? Briefly explain your answer. BCL11 Actin

. All mutations that abolish function of the Rho termination protein in E. coli are conditional mutations;no cells with null mutations of the Rho-encoding genehave ever been isolated. What does this tell you aboutthe rho gene and its product?

33. Expression of the muscle specific protein dystrophin is important in the functional formation of muscle tissue by A. integrating the internal cytoskeleton through a transmembrane complex with the extracellular matrix.  B. aiding transcription factors in entry into the muscle cells nucleus  C.degrading non-muscle cell proteins.  D. none of these

Consider the mechanism of the enzyme RNase:   What would happen to the Km (i.e., would it increase, decrease, or stay the same) if the his12 was mutated to a lysine? Explain.   What would happen to the Kcat (i.e., would it increase, decrease, or stay the same) if the his12 was mutated to a valine? Explain.

siRNA and CRISPR/Cas9 each interfere with gene expression by a sequence-directed mechanism. A. Identify the target macromolecule (DNA, RNA or Protein) of a specific siRNA/RISC andCRISPR/Cas9 complexsiRNA:CRISPR/Cas9: B. If a scientist would like to permanently turn off expression of a particular human gene inthe liver for the lifetime of an individual, which of these techniques would bepreferable? Briefly explain why

A. Based on this data, draw a conclusion about the promoter elements that Caudal specifically upregulates.  B. Dr. Juven-Gershon also tested Caudal activation of core promoter sequences from twoother genes. Similar to the first experiment, one was DPE-dependent (from the E74Bgene), and the other was TATA-dependent (from the Adh gene). However, these two corepromoters lacked the BREU motif. The results from these additional core promoters areshown below. Based on these results and those shown above, propose a hypothesis thatexplains the differences in Caudal-mediated upregulation among all the different corepromoters Dr. Juven-Gershon tested. C. To test your hypothesis from Question 3B, you plan perform the same method of genereporter assays that Dr. Juven-Gershon has done. However, you will need to do somemutations to alter the core promoters. Make diagrams or clearly describe all the variouscore promoters mutants you wish to test. These include your controls, as well as any…

The promoter consensus sequence at the -10 BOX in the bio gene in E. coli was TAGACT; however, a transversion occurred which changed the G nucleotide to T, what outcome(s) are likely?   a. transcription levels would decrease because the promoter would be weaker   b. nothing would happen because the promoter would not change the mRNA sequence   c. the mutation would block RNA polymerase from binding to the DNA   d. transcription levels would increase because the promoter would be stronger   e. the bio gene does not require a functional promoter

1. enzymes that catalyze histone acetlation are closesly associated with transription factors, which are proteins that promote transcription. why is this a good biochemical strategy? 2. sp1 is a sqeuence specific human DNA binding protein that binds to a region on the DNA called the GC box, a promoter element with the sequence GGGCGG. Binding of Sp1 to the GC box enhances RNA polymerase 2 activity 50- to a 100 fold. How would you use affinity chromatography to purify SP1?