Genetics lab Fall 1998

HAN 36 Tuesday 1:30-5:00 Office hours: 10-11 M, T; others by appt; phone 359-4377; email gilchris@sar.usf.edu Dr. Wagoner will also assist in the lab. His office hours will be posted.

Genetics lab will be a mixture of "cookbook" learn the technique labs and discovery labs. There will be two lines of inquiry that will continue throughout the semester for each group concerning sea urchins (Lytechinus variegatus) and fruit flies (Drosophila melanogaster). Each lab team will be assigned a specific starting point for the inquiry labs, but the direction of the inquiry will be left to the teams. Students planning to take only the first module of lab must notify the instructor during the first lab (notebooks for these students are due the last Friday of the module).

All students should bring paper towels, eye safety glasses, and disinfectant (eg lysol). A drawer in the lab will be assigned for each pair of students. Close toe shoes and knee length attire should be worn in lab for reasons of safety. Students not meeting safety requirements will not be permitted to work in the lab. NO STUDENT WILL BE PERMITTED TO WORK IN THE LAB ALONE. All glassware should be cleaned and put away. Any unlabeled material left on desk tops will be discarded.

The general lab manual for the course is Genetics Laboratory Investigations by Gardner, Mertens, and Hammersmith. Evaluation for the lab is based on the lab notebook, technique quizzes and two formal lab reports on the inquiry labs. Students should note that lab poise (organization, independence, lab safety) is also observed for the class. BEFORE ANY LAB IS STARTED, METHODS AND PROCEDURES MUST BE APPROVED. All notebooks are due the last Friday of classes by 5 pm EST.

Inquiry labs for Lytechinus (this will begin week 6)

Lytechinus variegatus occurs in the Atlantic, Gulf of Mexico and Caribbean. It can be found in a variety of color morphs along its range. Development times generally depend on the temperature of the culture waters. For this lab, students will embark upon the exploration of gene regulation during development. It is necessary to observe and record a "normal" set of developmental events for comparison to experimentals. Alkaline phosphatase is expressed early in development and increases in expression as the embryo ages. It is generally localized in the gut (mesoderm). It is also interesting that most of the mRNA used in the gastrula stage of the larva is maternal.

Students should consult primary literature concerning echinoderm development available in the library and online. After establishing a normal development time, students should construct a preliminary plan of attack on determining the distribution of alkaline phosphatase and its expression in the local urchin species.

References

Coffman, JA and EH Davidson. 1994. Regulation in gene expression in the sea urchin embryo. J. Marine Biological Assoc of the United Kingdom 74(1): 17-26

Gehring, WJ. 1985. The molecular basis of development. Scientific American 253(4): 152-163

Inquiry lab with Drosophila (this will begin week 1)

SEX! Now that your attention is focused, we will begin to examine fruit fly mating. Often in introductory labs, the emphasis is on the mating product---how many offspring of a particular phenotype are produced. We will not only view this aspect of reproduction, we will also note mating behaviors of the flies. Many of the stocks maintained in cultures are highly inbred. This can sometimes affect the fertility rate for the flies. There are several genes that have been indicated in mating behaviors including fickle, spinster and satori. Fickle males have highly variable mating spans and mate numerous times, spinster females reject courting males, and satori males attempt to mate with other males. When flies mate, the male orients to the female and "sings" by extending a wing and vibrating it rapidly. This mating can take several minutes, sometimes hours for some mutations (see senior thesis by Jason Hackney).

Your task will be to make observations on "normal" mating with selected stocks and then to devise an experimental scheme to examine one of the above mating variations.

References

flybase http://www.flybase.bio.indiana/

Drosophila virtual library www.ceolas.org/fly

Lab syllabus