May function in ocular mucus homeostasis. Expressed corneal epithelial cells, conjunctival goblet and epithelial cells and lacrimal gland cells (at protein level). Expressed by mucous cells of the submandibular gland and submucosal gland of the trachea. Expressed by middle ear epithelial cells. Down-regulated in Sjoegren syndrome patients (at protein level). According to the Genome Reference Consortium, the reference genome GRCh38/hg38 is in conflict with the sequence shown here. Truncated N-terminus.