Question 2: You decide to test how the presence or absence of nucleosomes affects transcription using an invitro transcription assay in which a DNA template featuring a promoter and single reporter gene is transcribedwith the addition of specific factors in a test tube. You get robust transcription when you combine templateDNA, RNA Polymerase, NTPs, and four general transcription factors - TFIIA, TFIIB, TFIID, and TFIIE.However, if you assemble the template onto purified nucleosomes and purify the chromatin template, then youdon't get transcription even when all of the transcription components have been added.You decide to try a slightly different experiment where you first preincubate the template with all thetranscription components except NTPs, then assemble the template onto nucleosomes and purify the chromatintemplate. Now when you add the transcription components and NTPs, transcription proceeds just as well as itdoes when using the naked DNA template (compare lanes 1 and 3). You conclude that one or more of thetranscription factors must bind to the template and keep the promoter accessible.To investigate this phenomena in more detail, you carry out two additional kinds of experiments. In one, youleave out individual transcription factors during the preincubation (lanes 4 – 8). In the second, you leave outindividual transcription factors during the transcription assay (lanes 9-13). Transcription templates werepreincubated with none, all, or all minus one of the transcription components. The transcription assay wascarried out with all, or all minus one of the transcription components. Use this information and the data below toanswer the questions.factors presentduring:preincubationtranscriptiontranscript →→→→nakedDNA0 0 all -A -B -D -E -Pol all all all all allall all all all all all all all -A -B -D -E -Polrrrrr1 234DNA assembled into chromatin-5678910 11 12 13A) Which of the transcription components must be present during the preincubation to keep the template activeduring chromatin assembly? Explain your answer.B) Which of the transcription components form a complex with the template that is stable to chromatinformation and subsequent chromatin purification? Explain your answer.C) Which of the transcription components must be added during the assay in order to produce a transcript?Explain your answer.

Name: Question 2: You decide to test how the presence or absence of nucleos
Uploaded: 2024-03-20T06:42:41.000Z
Channel: Bartleby
Description: Question 2: You decide to test how the presence or absence of nucleosomes affects transcription using an invitro transcription assay in which a DNA template featuring a promoter and single reporter gene is transcribedwith the addition of specific fa