GO_REF:0000002

Gene Ontology annotation through association of InterPro records with GO terms

InterPro domains IPR001878 (CCHC zinc finger), IPR011545 (DEAD/DEAH helicase), and IPR036875 support nucleic acid binding annotation

GO_REF:0000003

Gene Ontology annotation based on Enzyme Commission mapping

EC 3.6.4.13 (RNA helicase) maps to RNA helicase activity

GO_REF:0000033

Annotation inferences using phylogenetic trees

IBA inference for SSU-rRNA maturation appears to be based on distant DEAD-box helicase family relationships rather than GLH-specific function

GO_REF:0000043

Gene Ontology annotation based on UniProtKB/Swiss-Prot keyword mapping

Keywords for helicase, RNA-binding, metal-binding, nucleotide-binding support multiple annotations

GO_REF:0000116

Automatic Gene Ontology annotation based on Rhea mapping

RHEA:13065 (ATP hydrolysis) correctly annotates the catalytic activity

GO_REF:0000117

Electronic Gene Ontology annotations created by ARBA machine learning models

ARBA correctly inferred P granule localization and JUN kinase binding

GO_REF:0000120

Combined Automated Annotation using Multiple IEA Methods

Multiple sources correctly infer ATP binding and zinc ion binding from domain architecture

PMID:10851135

Combinatorial RNA interference indicates GLH-4 can compensate for GLH-1; these two P granule components are critical for fertility in C. elegans.

GLH-4 is a germline-specific P granule component

"four putative germline RNA helicases, GLHs, are components of the germline-specific P granules in Caenorhabditis elegans"
GLH-4 contains CCHC zinc fingers distinguishing it from Drosophila VASA

"the GLHs are distinguished by containing multiple CCHC zinc fingers"
GLH-1 and GLH-4 function redundantly; double RNAi causes 97% sterility

"loss of both GLH-1 and GLH-4 results in 97% sterility"
Double knockdown results in under-proliferated germlines lacking oocytes

"glh-1/4(RNAi) germlines are under-proliferated and are without oocytes"
Sperm are produced but delayed and defective

"glh-1/4(RNAi) animals produce sperm; however, spermatogenesis is delayed and the sperm are defective"
P granules still form in double knockdown (GLH-2/3 remain)

"P granules are still present in glh-1/4(RNAi) sterile worms as revealed with antibodies against the remaining GLH-2 and GLH-3 proteins"

PMID:12435362

The GLH proteins, Caenorhabditis elegans P granule components, associate with CSN-5 and KGB-1, proteins necessary for fertility, and with ZYX-1, a predicted cytoskeletal protein.

GLH proteins interact with KGB-1, a JNK MAP kinase

"KGB-1 is a putative JNK MAP kinase that GLHs bind"
Interaction confirmed by yeast two-hybrid and GST pull-down

"GST pull-down assays independently established that these proteins bind GLHs"
kgb-1 deletion causes temperature-sensitive sterility with oogenesis defects

"A kgb-1 deletion strain has a temperature-sensitive, sterile phenotype characterized by the absence of mature oocytes"
CSN-5 and KGB-1 are necessary for fertility, similar to GLH-1/GLH-4

"Similar to the loss of GLH-1 and GLH-4, loss of either CSN-5 or KGB-1 causes oogenesis to cease"
Loss of CSN-5 or KGB-1 causes oogenesis to cease but not P granule assembly

"loss of either CSN-5 or KGB-1 causes oogenesis to cease, but does not affect the initial assembly of P granules"

PMID:21402787

PGL proteins self associate and bind RNPs to mediate germ granule assembly in C. elegans.

GLH-4 knockout combined with GLH-1 RNAi results in smaller P granules

"in glh-1(RNAi) glh-4(gk225) embryos in which both GLH-1 and GLH-4 were undetectable, PGL-3 was dispersed in both somatic and germline cytoplasm, and cytoplasmic granules smaller than wild-type P granules were detected throughout embryos"
PGL-3 shows irregular cytoplasmic localization in glh mutants

"PGL-3 was dispersed in both somatic and germline cytoplasm"

PMID:24746798

Germ-granule components prevent somatic development in the C. elegans germline.

Quadruple knockdown (glh-1, glh-4, pgl-1, pgl-3) results in sterility

"we severely compromised P granules by simultaneously knocking down factors that nucleate granule formation (PGL-1 and PGL-3) and promote their perinuclear localization (GLH-1 and GLH-4)"
Compromised P-granule integrity leads to somatic reprogramming

"compromising P granules causes germ cells to express neuronal and muscle markers and send out neurite-like projections, suggesting that P granules maintain totipotency and germline identity by antagonizing somatic fate"
P granules maintain totipotency and germline identity

"P granules maintain totipotency and germline identity by antagonizing somatic fate"

file:worm/glh-4/glh-4-deep-research-falcon.md

Deep research on GLH-4 function synthesizing primary literature on P granule organization and piRNA pathway fidelity.

GLH-1 and GLH-4 act redundantly to organize perinuclear P granules

"GLH/VASA helicases (GLH-1 and GLH-4) organize perinuclear P granules and adjacent condensates"
Required for piRNA pathway fidelity and self/non-self discrimination

"GLH-dependent self/non-self discrimination step associated with perinuclear localization of PRG-1/Argonautes"
Promote perinuclear localization of PRG-1, WAGO-4, and MUT-16

"Double loss disrupts perinuclear foci of PRG-1, WAGO-4, and MUT-16"
Essential for 22G-RNA amplification at piRNA targets

"reduces 22G-RNA production at piRNA targets"
Double mutants show piRNA target derepression and aberrant silencing of self genes

"piRNA-triggered silencing fails; canonical piRNA targets are derepressed while many endogenous self genes are aberrantly silenced"
DEAD-box helicases bind and remodel RNA/RNPs via ATP hydrolysis cycles

"DEAD-box helicases that bind and remodel RNA or RNPs; ATP hydrolysis drives cycles of RNA engagement/release"
ATPase cycle controls P granule condensate dynamics

"ATP hydrolysis drives cycles of RNA engagement/release important for condensate dynamics"
FGG repeats promote perinuclear enrichment

"FGG repeats in GLH proteins further promote nuclear periphery localization by interacting with FG hydrogels"