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Stress granules (SGs), formed by untranslated messenger ribonucleoproteins (mRNPs) during cellular stress in eukaryotes, have been linked to flavivirus interference without clear understanding. This study reveals the role of Zika virus (ZIKV) NS2B as a scaffold protein mediating interaction between protein phosphatase 1α (PP1α) and eukaryotic initiation factor 2α (eIF2α). This interaction promotes eIF2α dephosphorylation by PP1α, inhibiting SG formation. The NS2B-PP1α complex exhibits remarkable stability, resisting ubiquitin-induced degradation and amplifying eIF2α dephosphorylation, thus promoting ZIKV replication. In contrast, the NS2BV35A mutant, interacting exclusively with eIF2α, fails to inhibit SG formation, resulting in reduced viral replication and diminished impact on brain organoid growth. These findings reveal PP1α's dual role in ZIKV infection, inducing interferon production as an antiviral factor and suppressing SG formation as a viral promoter. Moreover, we found that NS2B also serves as a versatile mechanism employed by flaviviruses to counter host antiviral defenses, primarily by broadly inhibiting SG formation. This research advances our comprehension of the complex interplay in flavivirus-host interactions, offering potential for innovative therapeutic strategies against flavivirus infections. Author summary: Zika virus (ZIKV) belongs to vector-borne flaviviruses, associated with Guillain-Barré syndrome and neonatal microcephaly. Stress granules (SGs) which forms under stress in eukaryotic cells can interfere with viral replication. Although previous studies have indicated that ZIKV can interfere with SG formation, the precise molecular mechanism and function remain unclear. Exploration of the mechanisms by which ZIKV antagonizes SG formation may help to identify new antiviral approaches. Here, we found that ZIKV NS2B bridge PP1α and eIF2α to promote eIF2α dephosphorylation and SG inhibition. Meanwhile, Reciprocal inhibition of K48-linked ubiquitination stabilized NS2B and PP1α to further facilitate the dephosphorylation of eIF2α and the concurrent inhibition of SG formation. Conversely, we demonstrated that a mutant form of NS2B, NS2BV35A, which interacted solely with eIF2α and not PP1α, attenuated virus replication and mitigated neurotoxicity in brain organoid development. The NS2B-PP1α-eIF2α axis reveals a novel biological function of NS2B as a general mechanism for flavivirus evasion of host antiviral effects, providing new therapeutic strategies for antiviral study. [ABSTRACT FROM AUTHOR]