Plays a critical role in intestinal function by promoting the development of enteroendocrine cells (EECs) of the gastrointestinal tract and pancreas (PubMed:31217582). It is thereby required for normal enteroendocrine peptide hormone secretion (PubMed:31217582). Specifically expressed in the stomach, pancreas and intestine (PubMed:31217582). In gastrointestinal tissue, expression is primarily restricted to gastric G cells and duodenal enteroendocrine cells (EECs) (PubMed:31217582). Mice were born at the expected Mendelian frequency and do not show gross phenotypes at birth (PubMed:31217582). within the first days of life, mice however display reduced size, low body weight and substantially decreased survival (PubMed:31217582). Examination of fecal pellets and internal organs reveal abnormal digestive-tract function, as well as changes in the composition of the intestinal microbiome (PubMed:31217582). Defects are caused by impaired expression of gastrointestinal peptide hormones and development of enteroendocrine cells (EECs) (PubMed:31217582).