Distinct roles of two eIF4E isoforms in the germline of .

Germ cells use both positive and negative mRNA translational control to regulate gene expression that drives their differentiation into gametes. mRNA translational control is mediated by RNA-binding proteins, miRNAs and translation initiation factors. We have uncovered the discrete roles of two translation initiation factor eIF4E isoforms (IFE-1, IFE-3) that bind 7-methylguanosine (m7G) mRNA caps during germline development.

ifet-1 is a broad-scale translational repressor required for normal P granule formation in C. elegans.

Large cytoplasmic ribonucleoprotein germ granule complexes are a common feature in germ cells. In C. elegans these are called P granules and for much of the life-cycle they associate with nuclear pore complexes in germ cells.

Germ granules and the control of mRNA translation.

Germ granules are an evolutionarily conserved feature of germ cell cytoplasm and are critical for gametogenesis and embryonic development. Germ granules are highly enriched for RNA and RNA-binding proteins and are key centers for post-transcriptional gene regulation in germ cells. Over the last 20 years, the molecular events in germ granule function and formation in several organisms have begun to be revealed.