Maternal Larp6 controls oocyte development, chorion formation and elevation

Abstract

La-related protein 6 (Larp6) is a conserved RNA-binding protein found across eukaryotes that has been suggested to regulate collagen biogenesis, muscle development, ciliogenesis, and various aspects of cell proliferation and migration. Zebrafish have two Larp6 family genes: larp6a and larp6b. Viable and fertile single and double homozygous larp6a and larp6b zygotic mutants revealed no defects in muscle structure, and were indistinguishable from heterozygous or wild-type siblings. However, larp6a mutant females produced eggs with chorions that failed to elevate fully and were fragile. Eggs from larp6b single mutant females showed minor chorion defects, but chorions from eggs laid by larp6a;larp6b double mutant females were more defective than those from larp6a single mutants. Electron microscopy revealed defective chorionogenesis during oocyte development. Despite this, maternal zygotic single and double mutants were viable and fertile. Mass spectrometry analysis provided a description of chorion protein composition and revealed significant reductions in a subset of zona pellucida and lectin-type proteins between wild-type and mutant chorions that paralleled the severity of the phenotype. We conclude that Larp6 proteins are required for normal oocyte development, chorion formation and egg activation.

The elongation factor eEF1A2 controls translation and actin dynamics in dendritic spines

“…HEK293T cells were transfected with plasmids expressing FLAG-eEF1A2 SA and FLAG-eEF1A2 SE, and triplicate samples were immunoprecipitated using FLAG-agarose beads (Sigma-Aldrich). FLAG immunoprecipitates (~150-g protein) were reduced with 100 mM DTT at 95°C for 10 min before being subjected to trypsin digestion using the Filter Aided Sample Preparation protocol (70). Peptides were analyzed using a Q Exactive Plus Orbitrap mass spectrometer (Barts Cancer Institute, London).…”

LARP6C orchestrates posttranscriptional reprogramming of gene expression during hydration to promote pollen tube guidance

“…More recently, human LARP6 was found to regulate the localisation and translation of ribosomal protein (RP) mRNAs to cell protrusions, enhancing RP synthesis, ribosome biogenesis, and overall protein synthesis in migratory cells (Dermit et al, 2020). Furthermore, in zebrafish (Danio rerio), both LARP6 paralogs are required for normal oocyte development, chorion formation, and egg activation (Hau et al, 2020).…”

Immune cell networks uncover candidate biomarkers of cancer immunotherapy response

“…GREM1 is a cytokine, BMP antagonist, VEGF agonist, and is downregulated in human B cells exposed to the toxin TCDD, which causes immunosuppression in addition to other harmful effects [65,66]. LARP6 is an RNA binding protein that regulates multiple aspects of cell behavior, including collagen production [67]; our analysis predicts a role in B cell function and immunotherapy response for LARP6. The presence of G protein gamma subunit GNG4 in B-net and upregulation with response to therapy suggests a role in B cell activation, consistent with the importance of G-protein coupled receptor signalling in the humoural immune response [68].…”