Department Chair

Martha Skerrett, Ph.D., Chair and Associate Professor of Biology

Date of Award


Access Control

Open Access

Degree Name

Biology, M.A.


Biology Department


Gregory J. Wadsworth, Ph.D., Associate Professor of Biology

Department Home page

First Reader

Gregory J. Wadsworth, Ph.D., Associate Professor of Biology

Second Reader

Douglas P. Easton, Ph.D., Research Professor of Biology

Third Reader

Amy McMillan, Ph.D., Associate Professor of Biology


GRP170 is a large molecular chaperone found in the ER of all eukaryotes. The nematode Caenorhabditis elegans has two loci encoding GRP170: T24H7.2 (grp170a) and T14G8.3 (grp170b). The phenotypes of nematodes genetically deficient for either grp170a or grp170b were compared to a standard laboratory strain with functional grp170 loci. Worms that were deficient for grp170a developed 32% slower than the control strain. The loss of grp170a had a significant but modest reduction on the life span compared to the control strain. Worms deficient for grp170a also displayed significantly increased embryonic lethality and resulted in 6.9% arrested embryos. The loss of grp170b did not change the rate of development, lifespan, or affect embryonic lethality. These data suggested that grp170a has a more critical role in the physiologic processes associated with completion of development compared to grp170b. To investigate whether either of the two grp170 loci plays a protective role during ER stress, sensitivity of the grp170 deficient worms to the ER toxin tunicamycin was analyzed. A sublethal dose of tunicamycin (3 mg/ml) modestly slowed development of both the control strain and the grp170a deficient strain. Worms deficient for grp170b were unexpectedly resistant to tunicamycin and did not show a developmental delay in the presence of tunicamycin.