PMID:14704431

A map of the interactome network of the metazoan C. elegans.

High-throughput yeast two-hybrid screen detected MEG-2 interaction with EYA-1

"more than 4000 interactions were identified from high-throughput, yeast two-hybrid (HT=Y2H) screens"

PMID:18202375

MEG-1 and MEG-2 are embryo-specific P-granule components required for germline development in Caenorhabditis elegans.

MEG-1 and MEG-2 localize exclusively to P granules during embryonic germline segregation

"encode proteins that localize exclusively to P granules during embryonic germline segregation"
Loss of meg-1 and meg-2 causes P granule mis-segregation and sterility

"meg-1 mutants exhibit multiple germline defects: P-granule mis-segregation in embryos, underproliferation and aberrant P-granule morphology in larval germ cells, and ultimately, sterility as adults. The penetrance of meg-1 phenotypes increases when meg-2 is also absent."
meg-1 and meg-2 are required redundantly for germline development

"The penetrance of meg-1 phenotypes increases when meg-2 is also absent."

PMID:19123269

Empirically controlled mapping of the Caenorhabditis elegans protein-protein interactome network.

Independent validation of MEG-2/EYA-1 interaction in WI-2007 interactome dataset

"We present an expanded C. elegans protein-protein interaction network, or 'interactome' map, derived from testing a matrix of approximately 10,000 x approximately 10,000 proteins"

PMID:25535836

Regulation of RNA granule dynamics by phosphorylation of serine-rich, intrinsically disordered proteins in C. elegans.

MEG proteins are intrinsically disordered with serine-rich regions

"a group of intrinsically disordered, serine-rich proteins regulate the dynamics of P granules in C. elegans embryos"
MEG-1 and MEG-3 are substrates of MBK-2/DYRK kinase and PP2A phosphatase

"We demonstrate that MEG-1 and MEG-3 are substrates of the kinase MBK-2/DYRK and the phosphatase PP2A(PPTR-½)"
Phosphorylation promotes P granule disassembly, dephosphorylation promotes assembly

"Phosphorylation of the MEGs promotes granule disassembly and dephosphorylation promotes granule assembly"
MEG proteins are required redundantly for fertility

"The MEG (maternal-effect germline defective) proteins are germ plasm components that are required redundantly for fertility"

PMID:36196602

Specialized germline P-bodies are required to specify germ cell fate in Caenorhabditis elegans embryos.

MEG-1 and MEG-2 are components of a distinct germ-plasm condensate (germline P-bodies) that contains mRNA decapping/deadenylation regulators and the RNA-binding protein POS-1, separable from canonical P granules.

"In this study, we describe a second condensate type, germline P-bodies, that contains regulators of mRNA adenylation and decapping, the RNA-binding protein POS-1, and MEG-1 and MEG-2, two intrinsically-disordered proteins related to MEG-3 and MEG-4."
Germline P-bodies depend on MEG-1 and MEG-2 for efficient accumulation in the germline founder cell P4 (whereas canonical P granules depend on MEG-3 and MEG-4).

"P granules depend on MEG-3 and MEG-4 and germline P-bodies depend on MEG-1 and MEG-2."
MEG-1 and MEG-2 are required to maintain robust levels of P-body proteins and robust activation of mRNA deadenylation in the P4 blastomere.

"MEG-1 and MEG-2 are required to maintain robust levels of P-body proteins and robust activation of mRNA deadenylation in P4."
Germline P-bodies (dependent on MEG-1/2) are essential for maternal mRNA regulation and specification of P4 as the germline founder cell.

"Our findings indicate that, unlike P granules, ‘germline P-bodies’ are essential for maternal mRNA regulation and specification of P4 as the germline founder cell."

file:worm/meg-2/meg-2-deep-research-falcon.md

Falcon deep research report: Functional annotation of C. elegans meg-2 (Q21127/K02B9.2)

MEG-2 has no assigned enzymatic, catalytic, or transporter activity; it is a non-enzymatic intrinsically disordered/low-complexity protein acting as a condensate organizer/scaffold in post-transcriptional regulation.

"MEG-2 is not assigned a catalytic reaction, substrate specificity, or transporter substrate"
The strongest modern functional model places MEG-1/2 in P4-stage germline P-body-like condensates that control maternal mRNA deadenylation/decapping and germline founder-cell fate.

"maintains **germline P-body–like condensates** in the P4 blastomere to control maternal mRNA deadenylation/decapping and proper germline founder-cell fate."
MEG-2's acidic predicted pI (6.04) biases the MEG-1/2 pair toward granule disassembly, in contrast to the basic MEG-3/4 pair that favors assembly.

"predicted unphosphorylated pI **MEG-2 = 6.04** (acidic), compared with MEG-3/4 basic pIs. This supports a hypothesis that MEG-1/2 (including MEG-2) bias toward disassembly roles, while MEG-3/4 provide stronger assembly contributions."
meg-1 meg-2 embryos still assemble embryonic P granules yet are fully penetrant for Meg sterility, indicating MEG function is not reducible to visible P-granule assembly.

"meg-1 meg-2 embryos can still assemble embryonic P granules yet display fully penetrant Meg sterility"