The Hect domain and RCC1-like domain-containing protein 1, often abbreviated as HECTD1, is a protein that plays a role in cellular processes such as protein ubiquitination and regulation of gene expression. It contains a HECT (Homologous to the E6-AP Carboxyl Terminus) domain, which is involved in transferring ubiquitin to target proteins, marking them for degradation or altering their function. Additionally, the RCC1-like domain in HECTD1 is thought to be involved in the regulation of the cell cycle and DNA repair mechanisms. This protein is important for maintaining cellular homeostasis and responding to stress, contributing to overall cellular health and function.