| Category | Summary |
|---|---|
| Identity | - Gene/protein verified as **C. elegans mut-16 / MUT-16**, matching UniProt **O62011** and ORF **B0379.3** in the literature.<br>- MUT-16 is described as a **Q/N-rich, intrinsically disordered protein** that nucleates Mutator foci rather than a catalytic enzyme. (pqac-00000003, pqac-00000004, pqac-00000006) |
| Molecular role | - Primary role is **scaffolding/assembly** of the Mutator complex required for **secondary siRNA (22G-RNA) amplification**.<br>- Distinct MUT-16 regions recruit different client proteins; the **C-terminal disordered region** is necessary and sufficient for foci formation and supports phase separation. (pqac-00000000, pqac-00000004, pqac-00000021) |
| Complex/partners | - Recruits or is required for localization of **MUT-2/RDE-3, MUT-7, MUT-14, SMUT-1, RDE-2, MUT-15, RRF-1, RDE-8, NYN-1/2**.<br>- Loss of mut-16 disrupts colocalization/co-IP among mutator proteins, indicating it is the **core organizational hub** of the complex. (pqac-00000000, pqac-00000001, pqac-00000005) |
| Subcellular localization | - Localizes to **perinuclear Mutator foci** on the cytoplasmic side of germline nuclei.<br>- Mutator foci are **adjacent to but distinct from P granules** and associate with **nuclear pores** within germline nuage architecture.<br>- In somatic contexts MUT-16 is more diffuse and Mutator foci are far less prominent. (pqac-00000002, pqac-00000007, pqac-00000018, pqac-00000022) |
| Pathway context | - Functions in the **WAGO-class 22G-RNA branch** of RNAi downstream of primary triggers such as piRNAs and exogenous RNAi.<br>- Current model: target cleavage and **pUGylation by MUT-2/RDE-3** mark RNAs for RdRP-dependent 22G-RNA synthesis in Mutator foci; this branch is distinct from **CSR-1/EGO-1** licensing pathways. (pqac-00000014, pqac-00000015, pqac-00000019, pqac-00000020) |
| Key experimental evidence/assays | - **Mutant analysis/RNAi**: mut-16 loss abolishes Mutator foci and impairs germline and somatic RNAi.<br>- **Imaging**: fluorescent MUT-16 reporters show punctate perinuclear foci adjacent to P granules.<br>- **Co-IP/IP-MS** and **CRISPR deletion mapping** identified recruited partners and modular interaction regions.<br>- **FRAP**, heat stress, and **1,6-hexanediol** assays support condensate-like behavior. (pqac-00000001, pqac-00000005, pqac-00000021, pqac-00000022) |
| Quantitative/statistical findings | - In mut-16, about **~2,300 target genes** showed **>3-fold depletion** of mutator-dependent 22G-RNAs in one analysis.<br>- MUT-16 FRAP recovery showed **t1/2 = 7.2 ± 1.0 s** with recovery to **~35%** of pre-bleach intensity, consistent with mobile and immobile condensate fractions.<br>- P granules associate with roughly **~75% of nuclear pores**, relevant to spatial organization of adjacent Mutator foci. (pqac-00000011, pqac-00000021, pqac-00000015) |
| 2023-2024 updates | - **2023** work refined nuage architecture: P granules form a **toroidal shell** around other compartments, and Mutator foci occupy a distinct adjacent subdomain that preferentially associates with RNAi-targeted RNAs.<br>- **2024** work identified the **E granule** for specialized EGO-1-dependent 5′-region 22G-RNA production, sharpening the contrast between Mutator-foci/WAGO and E-granule/CSR-related functions.<br>- **2024** studies further connected Mutator-foci organization to Argonaute specificity and condensate immiscibility in germ granules. (pqac-00000008, pqac-00000009, pqac-00000010, pqac-00000013) |
| Applications/uses | - **mut-16 mutants** are widely used as functional tools to test whether silencing depends on **mutator-complex amplification** versus other RNAi branches.<br>- Used in studies of **transposon repression**, **heritable silencing/TEI**, **stress responses**, and **endogenous transgene silencing** as a pathway-defining perturbation.<br>- Expert reviews use MUT-16 as a model scaffold for studying how condensate compartmentalization can enhance precision while avoiding **runaway silencing**. (pqac-00000014, pqac-00000015, pqac-00000019) |


*Table: This table concisely summarizes the verified identity, mechanism, localization, pathway context, and recent advances for C. elegans MUT-16 (UniProt O62011). It is useful as a citation-backed functional annotation snapshot focused on evidence from the gathered literature context.*