TY - JOUR TI - Novel LOTUS-domain proteins are organizational hubs that recruit C. elegans Vasa to germ granules AU - Cipriani, Patricia Giselle AU - Bay, Olivia AU - Zinno, John AU - Gutwein, Michelle AU - Gan, Hin Hark AU - Mayya, Vinay K AU - Chung, George AU - Chen, Jia-Xuan AU - Fahs, Hala AU - Guan, Yu AU - Duchaine, Thomas F AU - Selbach, Matthias AU - Piano, Fabio AU - Gunsalus, Kristin C A2 - Buszczak, Michael A2 - Sengupta, Piali A2 - Buszczak, Michael VL - 10 PY - 2021 DA - 2021/07/05 SP - e60833 C1 - eLife 2021;10:e60833 DO - 10.7554/eLife.60833 UR - https://doi.org/10.7554/eLife.60833 AB - We describe MIP-1 and MIP-2, novel paralogous C. elegans germ granule components that interact with the intrinsically disordered MEG-3 protein. These proteins promote P granule condensation, form granules independently of MEG-3 in the postembryonic germ line, and balance each other in regulating P granule growth and localization. MIP-1 and MIP-2 each contain two LOTUS domains and intrinsically disordered regions and form homo- and heterodimers. They bind and anchor the Vasa homolog GLH-1 within P granules and are jointly required for coalescence of MEG-3, GLH-1, and PGL proteins. Animals lacking MIP-1 and MIP-2 show temperature-sensitive embryonic lethality, sterility, and mortal germ lines. Germline phenotypes include defects in stem cell self-renewal, meiotic progression, and gamete differentiation. We propose that these proteins serve as scaffolds and organizing centers for ribonucleoprotein networks within P granules that help recruit and balance essential RNA processing machinery to regulate key developmental transitions in the germ line. KW - P granules KW - germ granules KW - IDR KW - LOTUS KW - vasa KW - phase separation JF - eLife SN - 2050-084X PB - eLife Sciences Publications, Ltd ER -