Effector that suppresses plant defense responses during the early stages of pathogen infection. Suppresses cell death induced by effectors and PAMPs in plant hosts (PubMed:21653195). Acts as a modulator of histone acetyltransferase (HAT) in plants. Avh23 binds to the ADA2 subunit of the HAT complex SAGA and disrupts its assembly by interfering with the association of ADA2 with the catalytic subunit GCN5. As such, Avh23 suppresses H3K9 acetylation mediated by the ADA2/GCN5 module and increases plant susceptibility (PubMed:28318979). Interacts with host histone acetyl transferase SAGA complex subunit ADA2. Location into the host nucleus is required for virulence. Expression is strongly up-regulated during the early stages of infection. The RxLR-dEER motif acts to carry the protein into the host cell cytoplasm through binding to cell surface phosphatidylinositol-3-phosphate. The two internal repeats IR1 and IR2, in the C-terminus, are required for the interaction with host ADA2. Leads to reduced virulence on etiolated soybean hypocotyls. Belongs to the RxLR effector family.