Regulation of lipid storage in Saccharomyces

cerevisiaeShaelie Harper McDonough-Stukey Lab

A Little History

• How do cells “know” when they have made enough lipid?

• Previously, Cheryl Jacobs had isolated a mutant (114) we

believe is defective at sensing lipid amounts

• My work this summer was to begin characterization of the

mutant

Growth Phenotype (clumpy vs. normal)

• Within a tetrad, it can vary what Within a tetrad, it can vary what strains are clumpy and which aren’t strains are clumpy and which aren’t

• If the ratio is 2:2 within a tetrad, this If the ratio is 2:2 within a tetrad, this means there is only 1 mutationmeans there is only 1 mutation

Clumpy Normal

Gas Chromatography data

•To the top is a picture of the GC at Hope College

•To the left is an example of the data collected by the GC

•Each Peak represents a different fatty acid, and

its relative amount present in each cell

Data Tables

•By creating data tables, it

is easier to make

comparisons and

conclusions for each individual

strain

Fatty acid Amount and Composition

Comparison of whole cell FA quantity

02000400060008000

10000120001400016000

1A 1B 1C 1D

Strain

FA

am

ou

nt

(no

rmal

ized

to

tal

GC

pea

k ar

ea)

Whole cell FA composition

0

10

20

30

40

50

10:0 12:0 14:0 16:0 16:1 18:0 18:1 26:0

FA species

Per

cen

t o

f to

tal F

A

sup114

diploid

w303-1a

•These charts are compiled after analyzing the data from the GC and

organizing it onto spreadsheets (shown on the previous slide), so we can

compare different strains

Result summaryTetrad Spore FA

Amount

Clumpy

Growth

1 A Wt NC

B Wt NC

C +++ C

D +++ C

2 A NC

B C

C C

D NC

3 A C

B Wt NC

C +++ C

D NC

4 A NC

B C

C NC

D C

6 A NC

B C

C C

D NC

7 A NC

B C

C C

D NC

8 A Wt NC

B +++ C

C +++ C

D wt NC

•Clumpy Growth is inherited in a single gene manner (2:2 inheritance)•Preliminary results indicate that elevated fatty acid amount is correlated to growthhabit, and is a single gene mutation

Conclusions

• By examining inheritance patterns we are able to see

– Clumpy growth habit is correlated to elevated FA amount

– Elevated FA amount is a recessive single gene trait

Credits

• REACH• Dr. McDonough and Dr. Stukey

• Rachel Van Kempen• Caitlin Rice