BIO308: Cell Biology Dr.
Karen Bernd
Classes: TR 8:30-9:45 Chambers 1006
Labs: Wednesday
1:30-4:20 or Thursday 1-4 Dana 220
kabernd@davidson.edu
Watson 289: 894-2889
In order to understand how something works it is sometimes easiest to break it into its smallest parts, figure out how they work and build up from there. It is known that the 'smallest part' of an organism is the cell. Research has shown that from organisms having only one cell (bacteria and yeast) to those with many multicellular organs (plants, insects and animals) complex sets of interactions between cellular components control how cells live and die. We will cover the basic parts of the cell in the context of these interactions by comparing normal and 'diseased' systems as case studies. The textbook and accompanying computer animations will be used as reference material and scientific journal articles on related topics will be used to bring the concepts into a broader context. The goal is to understand the concepts committed to textbooks, to be able to critically analyze current dogma and to suggest what the next questions might be and what approaches can be used to investigate them.
Required materials
Molecular Biology of the Cell (4th edition) by Alberts et al.Available
in the bookstore
Cell Biology Interactive CD-ROM-- Packaged with the text. If
buying a used textbook, be sure it has the CD-rom
Bio308 Laboratory Manual-- Provided as links from homepage. Download
and print.
Our study will follow the the example of cellular organization. Cellular processes are equisitely intertwined and balanced, therefore our case studies will draw on multiple chapters, animations and web readings. A Course Guide containing discussion questions is included as part of the syllabus. Use these to help you focus your reading and class preparation.
Class
periods I
expect class participation so you must come to class and be prepared.
It is an 8:30 class so do what you must to get here awake and alert.
We will be using a case study approach where a particular disorder provides
the framework for a discussion of topics in Cell Biology. WORDS OF WIDSOM
FROM PREVIOUS STUDENTS:
During the class period laboratory concepts will be introduced. The labs are
designed to let you 'do science'. They give you hands-on experience with commonly
used tools of cell biology and allow you to apply the principles covered in
the lecture period. This overlap should underscore the fact that the
lab and lecture portions are integrated to allow fuller understanding and reinforcement
of concepts
Laboratory sessions will be divided into two units. In the first techniques used to characterize the yeast mating reaction will be introduced and you will design experiments to investigate extracellular and intracelular signaling. In the second unit you will characterize yeast strains that are defective in the mating process. Because research requires planning and technical training as well as the ability to interpret data and communicate those results, each unit concludes with an individually written assignment. Throughout the semester there will be online assignments in Blackboard. Surveys are not graded but pre-post lab assignments are. The Blackboard assignment scores are part of your lab grade.
Attendance policy and Participation: Your participation in class is noted and graded (see grading below). Voluntary participation is looked on very favorably but keep on top of the material since questions will also be asked. It is in your best interest to be present since attendance is expected. An 'A' for participation requires preparation and participation in class that is consistent and of very high quality. (If you did not complete a written assignment you would expect to get a '0' on it. Not coming to class, coming to class unprepared or never speaking is equivalent to forgetting to complete this assignment and will be evaluated as such.)
Lab meets from 1-4 or 1:30-4:20 on the designated day. It should
go without saying that you will not miss lab or make other appointments that
coincide with your entire1-4pm or 1:30 - 4:20pm laboratory period. Failure
to follow this rule will cause a
penalty of -4pt from your final course grade.
We will work with live organisms that require certain amount of growth
time between steps. This means that some lab set up or observations must
be made outside of scheduled lab sections. During those times each group
must coordinate how and when you will meet. Regardless of who is performs
a certain task, every person is responsible for completing the procedures and for
making sure that you have the data. The Cell Bio site on Blackboard includes
group 'file exchanges' that lab groups can use to store and distribute
material.
Questions regarding the material
covered in a written assignment, how to prepare for class, or how to study
can be made at any time. Ask early and often! Talk to me during or after
class and lab, by email or in my office. I am happy to review first drafts
of papers if they are given to ahead of time (at least 2 days before
due date). I provide alot of feedback on exams and papers. Read the comments
so that you learn how to improve the next time. Progress is the expectation.
Questions regarding the evaluation of a written assignment (paper or
review) must be made within 10days of your receiving the graded material.
Contact me to make an appointment at a time that is convenient for both
of us.
Grades |
Grade Scale |
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Papers/Reviews/Exams and the Honor Code
Note
that the due dates/times are often outside of scheduled class meetings. All
assignment dates are scheduled now and will not change make sure you
put them in your schedule now. In
lab we will discuss that grant and job applications in science are
submitted by a certain deadline. Miss the deadline, by even a minute,
and you have no shot at that funding or job. Plan to turn in an assignment
with time to spare as late assignments
are not an 'option' to be chosen and are penalized (subtract
5% for 1min late and an additional 5% for every 60min after that)
I
must be notified as soon as possible for the rare possibility
of other arrangements (not the day or the hour it is due). You have
the schedule and have more than one day to complete the assignments.
Last minute computer/printer problems, 'walking up the hill', other
exams, papers, social functions, performances or sporting events
are not acceptable reasons for exceptions to this rule. Since hall
clocks vary in different buildings my computer
clock (standard across campus) or cell phone represents the
official time.
All of your reviews/exams are "take-home" exams. They are designed
to be completed in 2 hours (3 hours for final) but you will have more than
2 days. Exams are distributed by email on or before the day indicated on
the syllabus. The
exams are to be completed by you alone, without text, notes, or other written/verbal/telepathic
communication pertaining to the questions. Any use of such material is a violation
of the honor code and must be reported to me or the Dean of Students. Any knowledge
of a classmate using such materials must also be reported. Exceptions to this
rule are not allowed.
Written assignments are due as indicated in the syllabus. For Lab projects lab groups will, obviously, compile data together. You may discuss possible interpretations and share reference materials but all writing must be your own. Do not read each others drafts or discuss how you would describe or word particular sections of your paper. Be sure to include proper in-text references and end of paper bibliographies for all sources used-- this includes lab manuals and online resources as well as texts and journal articles. Bibliographic references to texts and articles must follow the style and format used in the journal Cell. (see http://www.cell.com/misc/authors.shtml). References to online resources must follow the MLA format for online sources (see http://www.bedfordstmartins.com/online/cite5.html#1 ). There is no such thing as the 'three source rule' and not providing proper credit is plagiarizing. Read the DEPARTMENTAL STATEMENT ON PLAGIARISM. If you have questions--- ASK BEFORE YOU TURN SOMETHING IN.
Accommodations for Students With Disabilities: I am happy to provide accommodations for students with learning or physical disabilities. If you are a student with a learning disability documented by Davidson College please identify yourself to me within the first two weeks of class so that arrangements can be made. Students with other disabilities are encouraged to self-identify so that we may discuss if there is any way in which I can make accommodations that will enhance your learning experience. All such discussions will be fully confidential unless you otherwise stipulate.
| Week | |
| 8/27 | Lab overview
LAB MEETS FIRST WEEK Blackboard Survey DUE BY FRIDAY 8/31 5pm Lab Safety/ Microscopy/ SterileTechnique/Brainstorming |
| 9/3 | Quiz
1 due Tuesday Sept 4th 11:59pm (covering
safety/microscopy/sterile technique AND reading for week of this
week) |
| 9/10 | Quiz
2 due Tues Sept 11th by 11:59pm (covering results from last
week and reading for this week) Unit 1: 'The Effect' Part I -changes over time What happens during long term exposure? |
| 9/16 | Quiz
3 due Tuesday Sept 18th by 11:59pm (covering
results from last week and reading for this week) Unit 1: 'The Effect' II- How much mating is 'normal'? |
| 9/24 | Quiz
4 due Tuesday Sept 25th by 11:59pm |
| 10/1 | Mini
unit: How do scientists
communicate? Grants and Funding |
| 10/8 | Unit 2: New
and special for Fall 2007 See instructions for final project and final
article in lab manual links. |
| 10/15 | DUE: Funding Opinion Paper due Beginning
of your lab period. We will discuss the opinion papers
at beginning of lab Overview of curriculum vitae assignment Prepare for next weeks' experiments |
| 10/22 | DUE in
lab: Curriculum vitae |
| 10/29 | Wed: Perform glucose metabolism
and GSH level assays. Thurs: Deflagellate cells and measure length and force during 2hr flagella regeneration period. |
| 11/5 | Analyze data: including graphs, representative pictures, statistical analysis. Begin literature search |
| 11/12 | Bring relevant articles. W.O.P. |
| 11/19 | (Thanksgiving Break) |
| 11/26 | Your
initial sections of lab article posted to Blackboard by 8:30am
Tuesday Nov 27th. Revisions are due in your laboratory period. |
| 12/3 | Lab cleanup Course evaluations |
| 12/10 | Optional Class days-- no scheduled lab |
BIO308
Cell Biology: Class Syllabus
Chambers 1006 TR 8:30-9:45am
Required Text: Alberts et al. Molecular Biology of the Cell, 4th Edition
CD-ROM-- one of the following is supplied with the text. 'reading' can
be done from either.
CBI refers to Cell Biology Interactive-- the CD-ROM Packaged with
Alberts
To use CBI: Some computers have problems running this CD-rom's
platform. If installing and clicking on the CBI icon doesn't work use the
following work-arounds.
To view movies and animations: open the disc, open the assets folder and select
files directly (the numbers in the syllabus are the 'names').
To view the molecular models you must have CHIME and Netscape on your computer.
Installing CBI should install these subprogram and both are part of computer
lab standard setups. Open Netscape Communicator. Under the Communicator File
menu choose open/ page in navigator. Use the dialog box to open the CBI folder
and the cbis folder within that. Choose any of the .htm files listed. This will
bring up an interactive interface with chapters on the right. From this interface
you can open the files listed below according to their numbers. Note: this interface
is unstable and may randomly quit. If it does, force-quit and restart.
ECB= Essential Cell Biology 2 (newer version of CD-rom included in some texts). This one gets around all the interface problems with CBI.
See syllabus for Biology Related Seminars
(in green). I
encourage you to attend them all. There are options on different afternoons
and evenings.
You
can earn extra credit for attending three (3). To
receive the credit you must:
a) attend the entire
seminar b) email me a brief overview of the seminar
within 72hours.
Each summary will add 1pt to the review most closely following the event (up
to 3 pt over the semester).
Ask a question: If you ask the seminar speaker a question
you can receive an additional 1pt. Provide the question and the response as
part of your summary.
| Week | Topic/Text Reading | |||||||||||||
| 8/27 | T | Introduction to course, Overview
of case studies |
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| R | Background: Why Cell biology is more than histology: Biological Membranes and Cellular components
Two classes reviewing background-- Need know the players before
anything else. What role do biological membranes play in the cell? What are the components that make them up? How are they important to its function? What are the fluid mosiac model and lipid rafts? How do biological membranes define organelles and what the organelles? (Is everything in the cell an organelle? what kinds of cells have organelles and what kinds do not?) |
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| 9/4 | T | Cellular components part II: No Cell is an island |
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| R | Communication is the key.
What are the types of extracellular signaling? Which types might
be faster/slower (why)? Given the diagram of normal thyroid signaling
what types of extracellular signaling are being used? What are the
types of cell surface receptors? (Some signaling molecules don't
use cell surface receptors-- how do they get in?) Given the symptoms
of Graves' disease what might be going wrong in the thyroid signaling
pathway? (Think of more than one possibility and how you might test
it) Thursday Sept 6th 7pm Chambers Gallery Friday, Sept 7th, 2PM |
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| 9/11 | T | II. So many signals--how does a cell know when to react? Specificity and the receptor
Interactions require the proper fit between receptors and ligands. Since all of the receptors we know are proteins we need to discuss proteins and protein folding before we can get to binding specificity. What are the amino acids and how do they come together and fold up into proteins? What are the levels of protein structure? What ways can you think of to change a protein's folding? What are binding sites and active sites? How do antibodies (CBI 24.1) exemplify binding specificity? Knowing that TSH, T3 and T4 are the hormones involved and TSH receptor is found on the thyroid cells and is activated by TSH what structural changes could result in an overstimulated thyroid? |
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| R | III. Getting the signals in--Conformational changes
to allow communication.
The ligands (signaling molecules) we have discussed are outside the cell. The plasma membrane is a barrier that these hormones cannot cross. In this class we will discuss how the receptor-ligand interaction allows a signal to cross the membrane even though the ligand stays 'outside'. The Chapter 10 reading reviews membrane proteins like the TSH receptor. The enzyme reading and CBI animations show the effects of interactions between molecules. What is the relationship between a proteins's conformation (shape) and its function? TSH is polar (can't get across the thyroid cell membrane by itself) how could it have an effect on the thyroid cell? Why don't all cells react to TSH? What could be happening to cause the thyroid to be overstimulated in Graves' patients? |
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| 9/18 | T | IV. Response Cascades and 2nd messengers.
What are second messengers? Why do we need them? Why do you think the cell uses these molecules as second messengers? What do they have going for them? What is a second messenger cascade? What are examples of some? The TSH receptor is a G-protein coupled receptor, what signaling cascade would you predict it is connected to? Stopping a cascade is as important as starting one, how do each of the cascades you listed stop and what makes the cell return back to resting levels of the signaling molecules? Graves' disease causes overstimulation, what could be wrong in the signaling cascade that would cause it to be overactive? |
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| R | Activation by another means & Introduction to paper discussion (how we'll do it)
The pdf is a good brief introduction to the immune system and immune responses. Read sections through 'Genetic factors'. This reading may seem to be a jump- what could antibodies have to do with Graves' disease right? Think about the connection between antibody form and function. How does the body realize that it 'should' mount an immune attack? What happens during an immune response? What happens (to the body) when the immune system loses the ability to differentiate between self and non-self? How could autoimmune diseases be related to an overactive thyroid? Introduction to paper discussion (how we'll do it) |
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| 9/25 | T | Paper 1: A. Hammes et
al. 2005. Role of endocytosis in cellular uptake of sex steroids. Cell 122;
751-762. |
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| R | Discussion of Hammes et al. (2005) paper Thursday Sept 27th 4:30PM |
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| 10/2 | T | Introduction to Case Study 2: Bipolar Disorder
Review parts of synapse/overview of normal nerve
transmission
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| R | The players: Neurotransmitters and their receptors
Why might the fact that amino acids, nucleotides/nucleosides and peptides are used as neurotransmitters cause potential problems in the body? What else do these molecules do? How does the body get around these problems? What are excitatory and inhibitory synaptic responses? What are the two basic classes of neurotransmitter receptors? How are they similar and different? What differences would you predict between the relative amount of hydrophobicity/hydrophilicity of a neurotransmitter and a neurotransmitter receptor? (why) |
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| 10/9 | T | Tale of 2 proteins: neuropeptide and neurotransmitter
receptor
Yes today's reading is long. Yes it covers alot of material but it should be review. DNA structure, transcription and translation are some of the topics you should have had at least twice in your biological career so we will move on to how these basic principles would relate to 'our' neurotransmitter at noradrenergic receptor. The animations are the short version-- focus on them and use the text to fill in rough spots. What is the central dogma? How would a neuropeptide get made (in general terms)? What are the basic parts of DNA, RNA, and proteins? What is the difference between hnRNA, mRNA and tRNA? How does RNA polymerase work and what does it make? How does it know where to start and stop? How does a ribosome work and what does it make? How does it know where to start and stop? If the DNA in every cell in your body is the same why don't your adipose (fat) cells secrete epinephrine? If the DNA contains all of the information why doesn't the ribosome just 'read' it? Why have intermediate steps? |
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| R | More protein manufacturing (finish translation)
Now the neuropeptide is made or the tyrosine has been enzymatically
modified into epinephrine and they end up in the cytosol. How does
the polar molecule get into the synaptic vesicle? Direct access provides
one method. (we will see others) What is active transport? Which
types of signaling molecules may be more likely to use this approach?
Which cellular membrane would the molecule be actively transported
through?
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| 10/16 | T | Fall Break: No Class | ||||||||||||
| R | Protein #2: Neurotransmitter receptor
Neurotransmitter receptors need to be part of a membrane-- they are integral membrane proteins (also called transmembrane proteins). Like other proteins the receptors are made in the cytosol. How do they get into the membrane? How can they be made in an aqueous environment and end up with parts in the hydrophobic membrane and parts on either side of that membrane? A simple 'door' through the membrane can't be enough. (A door to a room does not let you become part of the wall). The process of inserting membrane proteins is known as protein translocation and is part of protein sorting. How are the 'right' proteins chosen for translocation? (Said another way-- why is a neurotransmitter receptor synthesized in the cytosol and translocated but the parts of a trimer G protein are synthesized in the cytosol and remain there?) When does translocation take place? Does it occur during translation or after the protein has been made? Is there translocation machinery on every membrane or can newly made membrane proteins only get into a membrane at certain organelles? Moving a protein across a membrane is thermodynamically unfavorable (to say the least) where does the energy come from that powers translocation? Be able to describe the translocation mechanisms and think about how you would be able to tell which one was being used (what are their similarities and differences). Thursday Oct 18th 4:30PM |
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| 10/23 | T | Continue discussing last reading | ||||||||||||
R |
How are the packages delivered? Secretion and the SNARE hypothesis
Now that the receptor is in the membrane and the neurotransmitter is in the synaptic vesicle how do we get them to the right place? Why do synaptic vesicles fuse with the plasma membrane of the nerve terminal and not with the plasma membrane at the nerve cell body? Why don't they fuse with the membrane of the lysosome? The 'easy' answer is that synaptic vesicles only fuse at the synaptic terminal because that's where the neurotransmitter is supposed to go. Releasing it anywhere else would be wasteful and possibly detrimental. The translocator gets the receptor 'into' the ER membrane but vesicles are needed to get the membrane protein to the dendrite membrane where it can function correctly. How do these vesicles form? How do they end up containing the right content? (things that are supposed to be delivered, not ones that should stay in the ER)? What is the difference in regulations level between constitutive and regulated secretion. |
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| 10/30 | T | Monday Oct 29th 4:00PM Continue discussing last readings |
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R |
Other types of intracellular traffic.
Of course cells don't only exocytose they also endocytose, recycle and transcytose proteins. All of these forms of traffic use vesicles. How are the vesicles similar and different? Given any experimental method you wanted could you tell them apart? If no--why not? If yes--how? How do the packages get there? Molecular roads and infrastructure.
Look at the video clip as an example of how the cell can change shape. Think about the kinds of structures that would be necessary to maintain those shapes. What are the components of the cytoskeleton? What do they have in common and how are they different. Are they rigid or flexible? Are they built once, remodelled sometimes or constantly changing? Why is this property important to cellular function? How could it effect cellular function if this property was altered? (Increased flexibility or increased rigidity) (Paper #2 and questions are now available on Blackboard. Questions
are due on Wednesday 11/7 BEFORE our discussion of the paper) |
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| 11/6 | T | Molecular roads and infrastructure.
Now we have a little better understanding of the cellular 'roads'.
Now we turn our attention to the engines that drive along those roads--
molecular motors. As with most cellular machines, molecular motors
are made of proteins. These proteins have certain specificities and
enzymatic activity that are important for their function. What are
the motors? How do they 'know' what cargo to bind with and what roads
to move along? |
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| R | questions due
Noon Wednesday 11/7 |
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| 11/13 | T | Finish Article
Discussion |
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| R | Thursday Nov 15th, 4:30PM |
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| 11/20 | T | Introduction to Case Study 3: Introduction to Werner's Syndrome
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| R | Thanksgiving Break |
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| 11/27 | T | Life of a Cell: Cell cycle and its regulation
Today's reading covers many of the details of the cell cycle. With
so much riding on its correct completion you can understand why the
cycle would have many checks and balances. What are some of the ways
that a cell determines it is 'ok' to go through the cell cycle? How
do positive and negative feedback play a role in the process? What
kinds of enzymes are involved? If a CDK need a cyclin in order to
be functional why aren't these proteins found in 1:1 ratios? (Are
there more CDK's or cyclins? How do they work together to regulate
the cell cycle). The Breast Cancer video clip illustrates what happens
when lack of control leads to too much cell division. In Werner's
there seems to be too little. Cells die and are not replaced leading
to death of the individual. Its a delicate balance, too much or too
little and problems occur. In class we will discuss the theories
that connect cell cycle regulation to the aging process. |
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| R | Final exam 'prequestions' will be
emailed to you on Thursday
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| 12/4 | T | No class (attending Amer Soc Cell Biol Meeting) Paper 3: Austriaco, Jr and Guarente 1997
PNAS vol94 9768-72 |
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| R | Why and how do cells die? Apoptosis and Death due to damage
10min presentations of your lab project |
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Both sections of the final exam will be emailed
to you by Monday December 10th |