Involved in TGF-beta pathway. Plays a role in male tail tip morphogenesis (PubMed:21408209). In males localizes to the nuclei and cytoplasm during tail tip morphogenesis (PubMed:21408209). In hermaphrodites localizes only to the cytoplasm during tail tip morphogenesis throughout the L4 stage (PubMed:21408209). Expressed at low levels in the tail tip in both males and hermaphrodites from the L4 larval stage. RNAi-mediated knockdown disrupts tail tip morphogenesis resulting in retention of the pointed larval tail tip in adult males (also known as the Lep phenotype). Belongs to the dwarfin/SMAD family.