title: Regulation of sperm-specific proteins by IFE-1, a germline-specific homolog of eIF4E, in C. elegans.
abstract: ABSTEACT: IFE-1 is one of the five C. elegans homologs of eIF4E, which is the mRNA 5' cap-binding component of the translation initiation complex eIF4F. Depletion of IFE-1 causes defects in sperm, suggesting that IFE-1 regulates a subset of genes required for sperm functions. To further understand the molecular function of IFE-1, proteomic analysis was performed to search for sperm proteins that are downregulated in ife-1(ok1978); fem-3(q20) mutants relative to the fem-3(q20) control. The fem-3(q20) mutant background was used because it only produces sperm at restrictive temperature. Total worm proteins were subjected to 2D-DIGE, and differentially expressed protein spots were further identified by MALDI-TOF mass spectrometry. Among the identified proteins, GSP-3 and Major Sperm Proteins (MSPs) were found to be significantly down-regulated in the ife-1(ok1978) mutant. Moreover, RNAi of gsp-3 caused an ife-1-like phenotype. These results suggest that IFE-1 is required for efficient expression of some sperm-specific proteins, and the fertilization defect of ife-1 mutant is caused mainly by a reduced level of GSP-3.
authors.affiliation: Department of Bioscience and Biotechnology, Bio/Molecular Informatics Center, Konkuk University, Seoul, Korea. ikawasak@mac.com
authors.forename: Ichiro
authors.initials: I
authors.lastname: Kawasaki
authors.forename: Myung-Hwan
authors.initials: MH
authors.lastname: Jeong
authors.forename: Yhong-Hee
authors.initials: YH
authors.lastname: Shim
mesh_terms: D000818:Animals; D017173:Caenorhabditis elegans / Q000378:metabolism*; D029742:Caenorhabditis elegans Proteins / Q000235:genetics / Q000378:metabolism*; D015536:Down-Regulation; D015180:Electrophoresis, Gel, Two-Dimensional; D039561:Eukaryotic Initiation Factor-4E / Q000737:chemistry*; D039642:Eukaryotic Initiation Factors / Q000235:genetics / Q000378:metabolism*; D008297:Male; D009154:Mutation / Q000235:genetics; D009928:Organ Specificity; D010641:Phenotype; D040901:Proteomics; D034622:RNA Interference; D017386:Sequence Homology, Amino Acid; D013094:Spermatozoa / Q000378:metabolism*
chemical_list: D029742:Caenorhabditis elegans Proteins; D039561:Eukaryotic Initiation Factor-4E; D039642:Eukaryotic Initiation Factors; C558781:IFE-1 protein, C elegans