I. Undergraduate Research-- Getting a biology degree without lab research experience is like getting a degree in tennis without ever playing tennis --take a look at this link for detailed information on the value of undergraduate research- click here. Read an open letter from a student about the value of undergraduate lab involvement (click here)
Over just the last 6 years, these students (among others) used their work in my lab to go on to great careers: RYAN BATES (now working at Anschutz Medical Campus, Univ CO Denver)
KULAN BATABAYAR (just finished a Ph.D. at A. Einstein in New York, just left for Cambridge England on a PostDoctoral fellowship)
TIMOTHY SILVERSTEIN (now in Ph.D. program at Mount Sinai New York)
THOMAS MORRISON (received Ph.D. at UNC, Chapel Hill, now working in their virus center)
JASON STAFFORD (now in a Ph.D. program at UT SW; four Nobel laureates are on that campus)
WILLIAM HOLLAND (received a BS, MS in our department, Ph.D. at University of Utah, now a PostDoctoral Fellow at UT SW)
JEFFERY TAYLOR JUERGENS (now in a Ph.D. program in Pharmacology at Univ CO Denver -AMC campus)
WebGURU: An IMPORTANT web site for undergraduate researchers: http://www.webguru.neu.edu/
THE NATURE OF RESEARCH -supporting funding for basic research (versus just "applied" research): "Barnett Rosenberg wasn't trying to cure cancer...wasn't working on cancer (or)....on any disease-related problem (or)....with human cells. All he was trying to do was to test a hypothesis about what would happen when dividing bacteria were placed in a strong electric field. Yet he may have saved the lives of more cancer patients than most of the cancer researchers in the world put together." ..."a very important (idea)...is that in science there is no such thing as useless information." Go to this web site: http://www.asbmb.org/Page.aspx?id=1916
photo: UCD undergraduate research students at the ASCB meeting in San Francisco, CA
"The normal attitude (of a scientist) is a disquieting sense of being wrong. The work is open-ended, the results uncertain, and decisions are "curiosity-driven." Lewis Thomas, Physician/Researcher.
"SUCCESS IN SCIENCE GOES ONLY TO THOSE
WHO ARE UTTERLY PARANOID ABOUT THINGS GOING WRONG AND UTTERLY OBSESSIVE ABOUT
PREVENTING MISHAPS." JMW SLACK.
1. Presentations on Undergraduate Research at Clarion University (Oct. 10, 2008), Northern Michigan University (Feb. 1, 2008), and at Southern Connecticut State University (Aug. 23, 2005), showing data on the educational value and tips on achieving a successful program. Click here for PowerPoint slides (requires pdf reader).
5 Funding Sources for Undergraduate Research (presentation at FASEB 2001)
2 GRANT WRITING "HOW TO." Presentation at Council on Undergraduate Research (CUR) Proposal Writing Conference
3. FASTLANE and Grants.gov...a "How To"; Presentation given at the CUR Proposal Writing Institute
For a "how to" on searching for scientific articles using PubMed, click here (pdf Adobe file). This info is to be used in my courses that require a student presentation on original research papers.
For instructions on how to make a PowerPoint slide for a large poster, click here
How to take Essay Exams (especially important for my upper level courses); click here.
V. Research Two main areas of our research: 1. Cell Division/Insulin Action and 2. Fertilization. See this summary; click here. OUR RECENT PUBLICATION was selected for a "highlight" article by the American Society for Biochemistry and Molecular Biology; see page 29 CLICK HERE
More specifically, insulin, progesterone, or IGF-1 addition to
the Xenopus oocyte induces the oocyte to undergo meiotic cell division
to produce the fertilizable egg. Click here to see a
figure of the biochemical paths for hormone-induced meiotic cell division. Click to see an
ANIMATION of the activation of PI turnover and calcium
release (requires Shockwave player; click on line at bottom of this page to
download software) in the induction of meiotic cell division in the Xenopus
oocyte. Click for further discussion of the role of
intracellular calcium in the induction of meiotic cell division.
Related to this work on the insulin receptor, we can also study the mechanism of action of insulin and the anti-diabetic drug metformin (Glucophage; click here for 1998 paper on metformin.) WE BELIEVE THAT THIS MAY BE THE FIRST CLINICAL ARTIFICIAL ACTIVATOR OF TYROSINE KINASES. Other work involves a demonstration of tyrosine kinase activation by both insulin and progesterone, and that this activation is required for phospholipase C stimulation.
For a YOUTUBE video of manual dissection of the Xenopus oocyte, click here.
For an ANIMATION of the oocyte to egg maturation and events of fertilization, click here (34 K Shockwave animation; see bottom of this page to download Shockwave player).
Our CURRENT MODEL for fertilization is that a lipid (called PA) is important in sperm-egg fusion and the release of calcium. Click here to view a FLASH ANIMATION that also suggests that IP3 (not Ca, or PLC) diffuses to produce the calcium wave at fertilization. We are currently examining whether PA directly activates phospholipase C (PLC) or acts through stimulation of Src tyrosine kinase; view a PowerPoint animation by clicking here (THEN click on "OPEN" and click anywhere on the PowerPoint image to start animation). We are also examining the role of this lipid PA in the acrosome reaction of sperm.
A major Fertilization event: after sperm-egg contact is the propagation of a slow Calcium "wave" from the sperm entry point to the opposite side of the cell (for a list of fertilization events in Xenopus fertilization, and their time of occurrence, click here). This wave of elevated calcium inside the cell is associated with a wave of contraction of the cell's surface and a wave of cortical granule exocytosis (CGE). The chemical links between the zygote and the fertilization envelope are broken due to enzymes released during CGE (along with destruction of sperm binding molecules located at the egg surface). So, after CGE, the egg rotates freely within the egg jelly and the heavier yolk side rotates so that it is on the bottom--this is gravitational rotation). Click here for two VIDEOS of these fertilization events.. To see a third VIDEO of a group of zygotes undergoing GRAVITATIONAL ROTATION, click here.
Another fertilization event: there is a transient contraction of the animal pole...pigment granules (most are located just under the plasma membrane) move toward the dark animal pole. Click here to view before and after pictures of fertilization showing this movement.
Ionophores are molecules that allow the Calcium ion to move across membranes- they can mimic sperm in that when an ionophore is added to an egg, it causes an increase of Calcium in the cytoplasm and this artificially activates the egg (parthenogenesis) and induces numerous fertilization events (the egg will start development but typically the cell dies due to lack of sperm genome and since sperm may induce other events). View a Shockwave video of addition of 10 ÁM A23187 (an ionophore) to Xenopus eggs- CLICK HERE. Look for the labels in the upper left corner for time after addition of ionophore and note the changes that take place in the dark animal pole at about 28-20 min. This experiment is one of many that support the idea that fertilization is largely due to an increase in Calcium in the cytoplasm. Video taken by Tim Silverstein (who is now in a Ph.D. program at Mount Sinai School of Medicine, NYC, in Molecular, Cellular, Biochemical, and Developmental Sciences).
At about 1 and a half hours after insemination, the first CLEAVAGE FURROW begins. To view a VIDEO, click here. What type of cleavage pattern does the Xenopus embryo show? (holoblastic, radial; and egg is mesolecithal). 4 cell Xenopus embryo:
POLYSPERMY: Fertilization in NaI (Grey 1982 paper) causes more than one sperm to enter the egg...each one starts the cleavage process -see photos CLICK HERE.
Click here for OTHER REALLY INTERESTING WEB SITES. (Covering Xenopus biology, oocyte maturation, fertilization and embryogenesis)
"This material is based upon work supported by the National Science Foundation under Grant No. 9631051." "Any opinions, findings, and conclusions or recommendations expressed in this material are those of the author(s) and do not necessarily reflect the views of the National Science Foundation."
Click here for Shockwave Plugin that is Required to View the Animations