Transcription factor that specifically binds AT-rich DNA sequences related to the nuclear matrix attachment regions (MARs) (By similarity). Negatively regulates plant innate immunity (PTI) to pathogens through the down-regulation of the PAMP-triggered FRK1 expression (PubMed:20738724). Positively regulates defense against fungal Verticillium infection (PubMed:21864046). Slightly expressed in roots. By Verticillium dahlia attack. The PPC domain mediates interactions between AHL proteins. Enhanced susceptibility to Verticillium wilt resulting in wilting, stunting and chlorosis. Overexpression of AHL19 results in a decreased flg22-induced expression of FRK1 (PubMed:20738724). Overexpression of AHL19 results in an increased resistance to Verticillium wilt (PubMed:21864046).