The role of UBA4 in the genome of the yeast Saccharomyces cerevisiae

David Roberts, Claire Romelfanger, George Sprague PhD,Morehouse College, Atlanta GA, University of Oregon, Eugene

OR

http://www.chateauneuf.dk/artikler/vini15.jpg

Saccharomyces cerevisiae

-Easy to culture

-Eukaryotic cells similar in complexity to plant and animal cells

-Reproduce sexually and asexually

-Exists in haploid and diploid states

-70% of the genome well elucidated

http://www.chateauneuf.dk/artikler/vini15.jpg

http://www.science.lsus.edu/documents/resume/94859/yeast3.jpg

UBA4Known functions of UBA4

UBA4 is a critical enzyme in the process of urmylation. Urmylation is involved in the following processes

-Urm1 activating enzyme (urmylation)

-Cell budding

-Invasive growth

-Psuedohyphal growth

-Response to oxidative stress

Why study UBA4?

-UBA4 is present in all eukaryotic organisms

-To establish the specific role of urmylation in its processes

-To establish UBA4 functioning beyond urmylation

Objective of study:

-To gain further insight into the genetic interactions of UBA4

Ubiquitination and Urmylation

Ubi4

E1Activating EnzymeUba1

E2 Conjugating EnzymeUbc4

E3 Protein LigaseUbr2

UBP2Ubiquitin Protease

Urm1

Uba4

?

?

?

Synthetic Genetic Analysis

Approximately 5000 single gene deleted mutants

UBA4

uba∆

YFG

yfg∆

Healthy Synthetic Sick

Synthetic Lethal

Results

Synthetic Sickness and LethalityMutants said to be synthetically sick demonstrated diminished growth when compared to healthy growing (wild type) mutants.

Synthetically lethal mutants demonstrated no growth when compared to wild type mutants.

Plate of mutants

Synthetic sick mutant

Synthetic lethal mutant

UBA4 synthetic lethal/sick genes sorted by function

Cell Organization and Biogenesis

Transcription

RNA Processing

Transport

DNA Repair

DNA MetabolismProtein Transport

Unknown

Metabolism

Protein Degredation

Signal Transduction

UBA4 synthetic lethal/sick genes that overlap with URM1 synthetic lethal/sick genes

Cell organization and biogenesis

Unknown

Protein synthesisMetabolism

Signal Transduction

Protein Transport

ConclusionsThe results suggest that UBA4 genetically interacts with 56 different genes which participate in the following cellular processes:

-transport

-cell organization and biogenesis

-transcription

-RNA processing

-DNA repair

-DNA metabolism

-protein transport

-protein degradation

-signal transduction

-metabolism

Furthermore 12 of these genes are known to be synthetically lethal or sick with urm1∆, suggesting that urmylation may be involved in the processes governed by these genes.

Projections for Further Study

-Subsequent synthetic genetic analysis trials must be conducted to determine whether or not the results obtained in this experiment are reproducable.

-Random spore analysis must be conducted to verify the existence of the genetic interactions believed to have been observed.

Acknowledgements

Spur ProgramStudents

Coordinators

Sprague LabClaire Romelfanger

Charles Kubicek

Kimberly Landreth

Steven Tersigni

Dr. George Sprague