Search
Now showing items 1-10 of 48
The unique roles of IFE-1, a germline-specific isoform of eukaryotic translation factor 4E, during gametogenesis
(East Carolina University, 2009)
Fertility and embryonic viability are measures of efficient germ cell growth and differentiation. During oogenesis, spermatogenesis and embryogenesis cells initially proliferate then differentiate into specific tissues. New proteins are required for both cell growth and differentiation, requiring qualitative and quantitative changes in protein synthesis. During late gametogenesis and early embryogenesis the expression of the appropriate proteins is a primarily due to translational control. Translational control of mRNAs is mediated in part by eukaryotic initiation factor 4E (eIF4E). eIF4E binds the methylated 5' cap of mRNA and recruits it to the ribosome. The nematode worm C.elegans expresses five isoforms of eIF4E (termed IFE-1 through 5). IFE-1 is expressed primarily in the germline and is the only isoform that associates with P granules by binding directly to PGL-1. P granules are ribonucleoprotein particles (RNPs) that contain stored mRNAs and proteins needed for oogenesis and early embryogenesis. Using a strain that lacks IFE-1, I assessed the translational efficiency of maternal mRNAs bound and not bound to P granules by polysome fractionation. Translation of pos-1, pal-1, mex-1, oma-1, ced-4 and glp-1 mRNAs was inefficient in the ife-1 strain relative to wild type worms. GAPDH (gpd-3) mRNA translation was not affected. We also observed differences in the pattern of expression of the MEX-1 protein during oogenesis. In males, secondary spermatocytes failed to complete cytokinesis at 25°C in absence of IFE-1. Males deficient of IFE-1 therefore lacked mature sperm. In addition, ife-1 spermatocytes prematurely accumulated pro-apoptotic CED-4, homolog to mammalian Apaf-1, during spermatogenesis. In ife-1 worms fertility was decreased by 80% due to decreased viability of both oocytes and spermatocytes. Our data indicate two unique roles for eIF4E (IFE-1 isoform) in late oogenesis and spermatogenesis. We suggest that IFE-1 preferentially recruits regulated mRNAs at critical times during germ cell development. ...
Investigating the Interaction of RecQL4 and Mcm10 in Drosophila melanogaster
(East Carolina University, 2014)
Accurate duplication and regulation of the eukaryotic genome requires precise coordination among multiple replication factors. RecQL4, the least characterized RecQ protein, is a 1208 amino acid protein containing a centrally ...
SPATIAL EXPRESSION OF MATRIX AND MATRIX RECEPTOR PROTEINS IN THE DEVELOPING SYNOVIAL JOINT
(East Carolina University, 2013)
Little is understood about the complex spatial and temporal molecular interactions necessary to form a fully functional synovial joint. Understanding molecular pathways and signaling within the developing joint continues ...
The involvement of cap-independent mRNA translation in cell fate decisions
(East Carolina University, 2014)
During cell stress many biochemical processes are shut down. For
example, global mRNA translation initiation is inhibited due to the
disruption of the cap-dependent mRNA recruitment mechanism. One
specific example of ...
Comparison of ZnO nanoparticles and ZnCl₂ induced germ cell apoptosis in Caenorhabditis elegans
(East Carolina University, 2014)
There is inadequate research data available on manufactured ZnO nanoparticles. Manufactured nanoparticles are widely used in various products and production of manufactured nanoparticles is becoming increasingly abundant. ...
The contribution of motility and chemotaxis in the Borrelia burgdorferi infectious life cycle
(East Carolina University, 2013)
Lyme disease has emerged as an increasing problem for people in the east and northeastern part of the United States. It can cause a chronic debilitating infection if left untreated and is difficult to diagnose. The illness ...
Three Generations, One Future: A Systematic Analysis on Nicotine's Effect across generations in C. elegans.
(East Carolina University, 2013)
Tobacco smoking is a worldwide epidemic that is responsible for diseases and death rates that surpass those attributed to a combination of other causes (e.g. cancer, HIV, accidents). A major mediator of tobacco-smoke related ...
Multiple Translation Factor eIF4G (IFG-1) Isoforms are Required for the Apoptosome-Dependent Activation of Germ Cell Apoptosis
(East Carolina University, 2010)
Apoptosis is a naturally occurring process during animal development required for the programmed killing and removal of injured cells. Cellular insult induces a switch in translation that allows for the rapid synthesis ...
[Delta]-catenin: implications in prostate cancer progression
(East Carolina University, 2014)
Prostate cancer (PCa) is the most commonly diagnosed cancer and the second most common cause of cancer death among men in the US. Due to the advances in research, the ability to detect and cure PCa has improved and led to ...
Drosophila Ctf4 is essential for genome stability and normal cell cycle progression
(East Carolina University, 2010)
Proper DNA replication and well-timed cell cycle progression are vital to the normal functioning of a cell. Precise coordination between these mechanisms' constituent proteins ensures their processivity while safeguarding ...