TMED1 belongs to the EMP24/GP25L family. It contains 1 GOLD domain and is widely expressed. TMED1 binds to its receptor IL1RL1 and results in the activation of DNA binding by nuclear factor NF-kappa-B or transcription from the IL8 promoter and most likely requires other proteins to elicit these activities. Dendritic cells from Peyer's patches (but not from spleen) express TMED1 in response to treatment with LPS. TMED1 may play a role in vesicular protein trafficking, mainly in the early secretory pathway. It may act as a cargo receptor at the lumenal side for incorporation of secretory cargo molecules into transport vesicles and may be involved in vesicle coat formation at the cytoplasmic side.