NIN and infection: At least ten genes encoding for isoforms of this enzyme are contained in the Medicago genome and, interestingly, two of them are induced during infection thread development within root hairs (Medtr3g073100, Medtr7g089950; Liu et al., 2019a), one of which (Medtr7g089950) in a NIN-dependent manner (Liu et al., 2019a).