Abstract

Lv Blimp1 can directly target downstream genes of macrophage-like phagocytes, including MAP1B, SLC46, TACC1, and COL3A1. • The regulatory networks of Lv Blimp1, MAP1B, SLC46, TACC1, and COL3A1 are specifically involved in the immune response of Litopenaeus vannamei. • Lv Blimp1 and COL3A1 as high-potential breeding targets for enhancing low-salinity tolerance and VpAHPND resistance in shrimp. • TACC1 is a promising candidate for improving WSSV resistance. Litopenaeus vannamei B lymphocyte-induced maturation protein 1 ( Lv Blimp1) is a transcription factor expressed in macrophage-like phagocytes that modulates immune responses via direct bactericidal activity, opsonization, and phagocytosis. However, the molecular targets and regulatory architecture by which Lv Blimp1 controls shrimp disease resistance remain poorly defined. In this study, ChIP-seq was performed in shrimp hemocytes to identify genome-wide binding targets of Lv Blimp1. Five core downstream genes (MAP1B, SLC46, TACC1, COL3A1, and LGMN) are directly regulated by Lv Blimp1 were identified through integrative analysis of ChIP-seq data, transcriptomes following Lv Blimp1 knockdown, and marker gene sets of macrophage-like phagocytes. Four targets (MAP1B, SLC46, TACC1, COL3A1) were verified as direct transcriptional targets after FIMO analysis and ChIP-qPCR. Distinct expression patterns and regulatory correlations were observed in public transcriptomic datasets under white spot syndrome virus (WSSV) infection, Vibrio alginolyticus ( V. alginolyticus ) infection, and low-salinity stress, indicating that stress-specific immune responses are orchestrated by Lv Blimp1 selective target engagement. Significantly altered expression of Lv Blimp1 and its targets was detected in Vibrio parahaemolyticus- resistant and WSSV-resistant shrimp families, with divergent expression profiles observed under distinct pathogenic challenges. This study constructs a context-dependent transcriptional regulatory network