To whom it concerns, 
       I  am  an indidvidual who is about to begin some research in
the science field of cellular and molecular biology over the summer.
Before I get started, I wanted to gain a very good foundation on the
knowledge of this field. So i have been doing independent work and
have come across some questions that I have not been able to
understand. The following question is one that I have had extreme
problem in solving. I need to thoroughly have a good explanation of
this problem. The information that I have found on this has not helped
me answer this question so i turn to you to help me out. I thank you
very much of your help and your time. So here is the question: This
question deals with  dynamic subcellular localization. It is as
follows:

Bacterial cells are now recognized as being often highly polarized,
exhibiting specialized structures at or near the ends of the cells.
This polarization is orchestrated by dynamic changes in the
subcellular localization of cytoskeletal and signal transduction
proteins. So here is the question: Describe the nature and functions
of dynamic subcellular localization in sporulation in Bacillus
subtilis or cellular differentiation in Caulobacter crescentus.

This question reuires very thorough and complete explanations. I
sincerely request someone to answer this question ASAP as i must
figure out this stuff before i begin my research in two weeks. Thank
you very, very much.

http://www.science.mcmaster.ca/Biology/faculty/Schellhorn/students3c03/Mike/index.htm

Interested in Caulobacter? Try a pubmed search for reviews. Its a
great, well understood system.

www.pubmed.com

Suggested search terms...

Caulobacter Cell Cycle then, click the review tab, you'll get a whole
bunch.  Assuming you are at a university, you can probably access any
of the papers.

Against my better judgement, here is a brief overview....seriously
though, if this is for an exam, shame on you - your only screwing
yourself over. If you plan on earning any degree, you might as well
earn it, esp. if you are thinking of med school.


Caulobacter crescentus -  The basic overview ? Caulobacter divides
asymetriclly, producing a swarmer and a stalk cell, the stalk cell can
immediately begin a second round of division, whilst the swarmer moves
to another location and degrades its flagella prior to division.

So, how does Caulobacter manage to divide asymmetrically without fail?  

CtrA Regulatory Network regulates flagella biogenesis, ftsZ, pili, replisome.
The network controls 26% of the cell cycle in caulobacter, including 95 genes.
Caulobacter produces 22000 molecules of CtrA, it is thought that this
is to minimize stoichiometric variations throughout the cell. The
timing of CtrA is tightly controlled, both the synthesis and
degradation occur rapidly and are tied to chromosome replication and
an unknown control respectively.

CtrA sileneces oriC.  Therefore it must be concentrated in the swarmer
cell and not in the stalked cell.

The resetable switch that ties CtrA synthesis to x-some replication
progress is tied to the methylated state of the P1 CtrA promoter.  In
its normal state, CtrA is methylated, as replication progresses a
methyltransferase progresses with the replication fork, fully
methylating the promotor.  This turns on the promotor.  It only
functions when hemimethylated.  The P2 promotor is autoactivated when
CtrA (from P1) accumulates to threshold levels.  This increases the
rate of production of CtrA.  When CtrA increases, amongst other
things, it activates the CcrM methyltransferase, which then can
methylate and inactive the P1 promotor. Varying chemistry at the poles
is responsible for the localization of CtrA as well as the pili
secreting proteins.


For my edification, what are you researching this summer? University?
Corperate? What does the lab deal with?

These questions are not for an exam. If they were an exam I could have
easily asked classmatesd or freidns for the answer. I've come here
because my science advisor has told me about this site nd says people
are really helpful on this. Pforcelli, you have given me tremedous
help and i thank you veyr much for it.  will be doing independent
research in the field of molecular biology. But in my university, we
have to do prelimiary work for it and these questions are a gudieline
that you should be able to answer. Thats why ir equested a thorough
explanation which i have not quite gotten for the other question on
overregulation. I understand that its' shameful to cheat and it
accomplishes absolutely nothing. I am simply trying to get a good
explanation on these questions so that i may udnerstand them and gain
enough background iformation. That said, it would be greatly
appreciated if a more thorough explanaton be given to my questions,
although if you would not want to help me, that is okay too. I'm not
begging for any answers. i want thorough explanantions. So if you
could, it would greatly help me. If not, then thanks for the help you
ahve provided thus far. So, i look forward to eharing from you
pforcelli or anyone else who may think i have bad intentions.

One, and only one comment in response to your comment....

But in my university, we
have to do prelimiary work for it and these questions are a gudieline
that you should be able to answer

Yes. You should be able to answer these questions.  I have given you
more than enough information to start yourself on the search for
answers - that is what research is all about.  Make use of pubmed,
make use of the wonderful texts that are available, and figure the
rest out for yourself.  If you can't interpret a journal article or a
chapter in a text, research isn't where you belong.  You need to be
able to interperet existing data and via that analysis come up with
new questions.  Good luck.,

Pforcelli

Ok thanks for your help ..however if u could pforcelli, clarify on the
overregulation problem a bit more as it is extremely difficult to find
any information on that...i have access to no books as i found out
they are chekced out at this time and online is not working hence i am
on this google answer site...that would be appreciated....  further
sermons would not be appreciated. as i have parents to tell me what to
do or not to do..thank you

What University do you attend? Go to your University Library- Biology
Journals section. All this information is searchable through PubMed.

If you were applying to work in my lab and I found that you were
getting all the info from Google Answers instead of doing the searches
and finding the info yourself, I wouldn't even let you in the door.

pforcelli has been very kind in putting up with your rudeness (further
sermons not appreciated). Your lucky he helped you at all. I wouldn't
have.

Hey Dops - 

Right on! The way I see it is, if this guy can't take all of our
advice and find the stuff on his own (especially with the more than
ample help give), he won't last long in whatever lab he manages to get
into.

One of the greatest things about science - I'm sure you will agree -
is the critical evaluation of all information presented.  I could have
easily made up suggestions for tellanish that were utter nonsense and
without critical evaluation sound great - any researcher that takes
things at face value without doing their own background work won't be
researching for long.