Insight into the interaction between the RNA helicase CGH-1 and EDC-3 and its implications

Abstract

Previous studies indicated that the P-body components, CGH-1 and EDC-3 may play a crucial role in the regulation of lifespan in Caenorhabditis elegans. Homo sapiens DDX6 or Saccharomyces cerevisiae Dhh1p (CGH-1 in C. elegans) could form complexes with EDC3 (Edc3p in yeast), respectively, which is significant for translation inhibition and mRNA decay. However, it is currently unclear how CGH-1 can be recognized by EDC-3 in C. elegans. Here, we provided structural and biochemical insights into the interaction between CGH-1 and EDC-3. Combined with homology modeling, mutation, and ITC assays, we uncovered an interface between CGH-1 RecA2 domain and EDC-3 FDF-FEK. Additionally, GST-pulldown and co-localization experiments confirmed the interaction between CGH-1 and EDC-3 in vitro and in vivo. We also analyzed PATR-1-binding interface on CGH-1 RecA2 by ITC assays. Moreover, we unveiled the similarity and differences of the binding mode between EDC-3 and CAR-1 or PATR-1. Taken together, these findings provide insights into the recognition of DEAD-box protein CGH-1 by EDC-3 FDF-FEK motif, suggesting important functional implications.

The RNA-binding activity of the TRIM-NHL protein NHL-2 is essential for miRNA-mediated gene regulation

“…We propose a model in which NHL-2, CGH-1, and IFET-1 work together to translationally inhibit some miRNA targets (Figure 9). In wild-type worms, these proteins work together to inhibit translation and may also help recruit decay factors such as PATR-1 and EDC-3, which competitively bind to CGH-1 (71), the deadenylation machinery PAN-2/PAN-3, and the CCR4-NOT complex. Individual loss of NHL-2, CGH-1, or IFET-1 have a minor effect on miRISC function, while the loss of function of two components significantly impacts miRISC activity, resulting in continued translation of the target mRNA, leading to developmental defects.…”

EDC-3 and EDC-4 Regulate Embryonic mRNA Clearance and Biomolecular Condensate Specialization

“…Additional factors such as LSm14 (CAR-1, for Cytokinesis, Apoptosis, RNAassociated-1), Ddx6 (CGH-1, for Conserved Germline Helicase-1), 4E-T (IFET-1, for eIF4E Transporter-1) and PatL1 (PATR-1, for PAT1 Related-1) are linked to decapping enhancement by promoting RNA binding activity, by stabilizing the active conformation of Dcp1/2, and by facilitating the formation of higher-order decapping assemblies [24][25][26][27][28][29][30] . In contrast, in Drosophila early embryos and C. elegans oogenesis, a complex formed of CAR-1, CGH-1, and IFET-1 represses translation and prevents mRNA decapping and decay 31,32 , suggesting molecular coordination between the two related processes.…”

“…The copyright holder for this preprint this version posted March 7, 2024. ; https://doi.org/10.1101/2024.03.04.583404 doi: bioRxiv preprint enhancement by promoting RNA binding activity, by stabilizing the active conformation of Dcp1/2, and by facilitating the formation of higher-order decapping assemblies [24][25][26][27][28][29][30] . In contrast, in Drosophila early embryos and C. elegans oogenesis, a complex formed of CAR-1, CGH-1, and IFET-1 represses translation and prevents mRNA decapping and decay 31,32 , suggesting molecular coordination between the two related processes.…”