Key result
Overexpression of ZCCHC3 in human cell lines severely restricted LINE-1 retrotransposition to 3% of control levels, while its knockdown increased retrotransposition over three-fold.
Why the study?
Cells possess defense mechanisms to protect against LINE-1 retrotransposition, but the specific factors involved are only beginning to be understood.
Absolute Event Rate: 3% vs 100%
p-value: p=<0.0001
ZCCHC3 is identified as a stress granule protein that strongly restricts human LINE-1 retrotransposition, expanding its known role beyond antiviral innate immunity.
ZCCHC3 suppresses LINE-1 in cell models; leaves open any cardiovascular genomic role.
Retrotransposons have generated about half of the human genome and LINE-1s (L1s) are the only autonomously active retrotransposons. The cell has evolved an arsenal of defense mechanisms to protect against retrotransposition with factors we are only beginning to understand. In this study, we investigate Zinc Finger CCHC-Type Containing 3 (ZCCHC3), a gag-like zinc knuckle protein recently reported to function in the innate immune response to infecting viruses. We show that ZCCHC3 also severely restricts human retrotransposons and associates with the L1 ORF1p ribonucleoprotein particle. We identify ZCCHC3 as a bona fide stress granule protein, and its association with LINE-1 is further supported by colocalization with L1 ORF1 protein in stress granules, dense cytoplasmic aggregations of proteins and RNAs that contain stalled translation pre-initiation complexes and form when the cell is under stress. Our work also draws links between ZCCHC3 and the anti-viral and retrotransposon restriction factors Mov10 RISC Complex RNA Helicase (MOV10) and Zinc Finger CCCH-Type, Antiviral 1 (ZC3HAV1, also called ZAP). Furthermore, collective evidence from subcellular localization, co-immunoprecipitation, and velocity gradient centrifugation connects ZCCHC3 with the RNA exosome, a multi-subunit ribonuclease complex capable of degrading various species of RNA molecules and that has previously been linked with retrotransposon control.
No takes yet. Share an insight, caveat, or question.
Goodier et al. (2023) studied LINE-1 retrotransposition. ZCCHC3 overexpression vs. Empty vector control was evaluated on LINE-1 retrotransposition rate in cell culture (p=<0.0001). Overexpression of ZCCHC3 in human cell lines severely restricted LINE-1 retrotransposition to 3% of control levels, while its knockdown increased retrotransposition over three-fold.
Synapse has enriched 5 closely related papers on similar clinical questions. Consider them for comparative context: