 |
| PROJECT NUMBER: 09 |
|
INSTRUCTOR(S):
L. Dickson, Howard University, Washington, D.C.
|
TITLE:
The Negative Transcriptional Regulation of Gene Expression
|
PROJECT DESCRIPTION:
A dynamic graphic illustration to facilitate understanding of the mechanism(s) of negative transcription regulation. |
DISCIPLINE:
Biology
|
|
|
SUBJECT AREA:
Molecular Biology: Regulation of Gene Expression |
GRADE-LEVEL:
Undergraduate |
INSTRUCTIONAL
GOAL: (competency that students should be able to demonstrate
upon completion
of the entire unit)
Students should understand that transcription is regulated by controlling RNA polymerase's binding to its promoter on DNA. The binding of the repressor prevents RNA polymerase binding. Repressor binding is abolished by its binding of inducer.
|
PERFORMANCE
OBJECTIVE: (use an action verb in a description of a measurable
outcome)
Students will learn the mechanism by which transcription is prevented or allowed by the binding or unbinding of the repressor protein. Students will learn that the repressor loses its ability to bind and block transcription when it binds its inducer.
|
RATIONALE:
(brief justification -- why you feel the students need to
learn this topic)
Biology students should know that most genes are not constantly synthesizing their gene products but that they can be turned on and off (i.e. regulated). This lesson describes the mechanism by which prokaryote gene expression is negatively regulated.
|
LESSON
CONTENT: (what is to be taught)
The loci in the regulatory region of the gene that bind RNA polymerase (the promoter) and the repressor (the operator) are described. The site where the inducer binds to the repressor changing its ability to bind the operator is described.
|
INSTRUCTIONAL
PROCEDURES:
a. Focusing event (something to get the students' attention):
The different molecules are shown with labels in different colors. There is an audio track and a written description to guide the students through the animation. |
b. Teaching procedures (methods you will use):
The teaching procedure is a |
c. Formative check (progress checks throughout the module):
Currently, there are no formative checks in this lesson. Formative checks should be added. |
d.
Student Participation (how you will get the students
to participate):
Beyond turning on the animation for the first time and turning it on to repeat it, there is no other student participation. Addition of student participation activities would improve this lesson. |
e. Closure (how you will end the module):
Providing specific examples of genes/operons that are regulated as described in the lesson would strengthen its significance. The first operon whose gene regulation was described was the lactose utilization operon on which this lesson is based. |
|
EVALUATION
PROCEDURES: (how you will measure outcomes to determine if
the material has been
learned)
A multiple choice quiz with feedback for both the correct and incorrect answers would be an effective evaluation procedure.
|
MAJOR
TECHNOLOGY:
Flash
|
OTHER
REQUIRED TECHNOLOGY: (what students will need in order to experience
this module online--plugins, viewers,
etc.)
Beyond having a computer with internet access and speakers, no additional technology is required. |
CONTACT
INFORMATION:
| First
Name: Leon |
Last
Name: Dickson |
| Email
Address: ldickson@howard.edu |
Phone: |
|
ABSTRACT:
"The Negative Transcriptional Regulation of Gene Expression" is a dynamic graphic illustration that attempts to facilitate the understanding of the mechanism of how the synthesis of RNAs from their genes in DNA is controlled. The various molecules involved are described and their differential ability to interact with each other is graphically represented in this animation. The access of the RNA polymerase to its binding site, the promoter, is shown to be blocked by the presence of the repressor binding to its binding site, the operator. The removal of the repressor by its binding to the inducer causing the repressor to no longer have the appropriate shape to bind the operator is shown. Once the repressor can not bind, the RNA polymerase can bind to the promoter, separate the double stranded DNA into single strands, and use the template strand of DNA to synthesize a RNA molecule. |