Title

Genetic and molecular characterization of genes involved in Caenorhabditis elegans germ line development

Date of Award

1997

Degree Type

Dissertation

Degree Name

Doctor of Philosophy (PhD)

Department

Biology

Advisor(s)

Eleanor Maine

Keywords

signal transduction, @ego

Subject Categories

Cell Biology | Genetics

Abstract

Cell-cell interactions control many cell fate choices during the development of multicellular organisms. In Caenorhabditis elegans, the distal tip cell (DTC) regulates the mitosis/meiosis choices of the germ cells. This cell signaling requires a putative signal from the DTC, encoded by the lag-2 gene, a putative receptor in the germline, encoded by the glp-1 gene, and at least one downstream effector encoded by the lag-1 gene. To identify additional genes involved in the glp-1 signaling pathway, genetic suppressors and enhancers of glp-1 mutations have been isolated; they are named sog (suppressor of glp-1) and ego (enhancer of glp-1) mutations.

My dissertation studies involve the genetic characterization of a sog-10 mutation and a set of ego mutations, and the molecular cloning of the ego-3 gene. The sog-10 mutation suppresses glp-1 (lf) germline defects and feminizes XX germline, indicating its role in both germline proliferation and sex determination. lag-1 and glp-4 are known genes whose mutations can enhance glp-1(lf). lag-1 mutations affect both germline proliferation and embryogenesis, while glp-4 mutations affect both germline mitosis and oogenesis. Finally, ego-3 mutations have multiple phenotypes indicating its role in multiple aspects of germline development as well as in somatic tissues. The predicted ego-3 gene encodes a novel protein. Its weak similarity with several enzymes suggests EGO-3 may be involved in protein-protein interactions. These studies suggest that these suppressors and enhancers of glp-1 may have functions in multiple aspects of development, as does glp-1 itself.

Access

Restricted

http://libezproxy.syr.edu/login?url=http://proquest.umi.com/pqdweb?did=736905481&sid=4&Fmt=2&clientId=3739&RQT=309&VName=PQD