Amnionless (AMN)

SPN	U550
HGNC	14604
MGI	1934943
PubMed	15845892
RGD	1308634
UniProt	Q9BXJ7
Wiki	Amnionless

Protein amnionless is is a type I transmembrane protein. It is thought to modulate bone morphogenetic protein (BMP) receptor function by serving as an accessory or coreceptor, and thus facilitates or hinders BMP binding. It is known that the mouse AMN gene is expressed in the extraembryonic visceral endoderm layer during gastrulation, but it is found to be mutated in amnionless mouse.

The encoded protein has sequence similarity to short gastrulation (Sog) and procollagen IIA proteins in Drosophila.Long isoforms are highly expressed in small intestine, colon and kidney (renal proximal tubule epithelial cells). Shorter isoforms are detected at lower levels in testis, thymus and peripheral blood leukocytes.

Reference

"The amnionless gene, essential for mouse gastrulation, encodes a visceral-endoderm-specific protein with an extracellular cysteine-rich domain."
Nat. Genet. 27:412-416(2001) [PubMed] [Europe PMC] [Abstract]

"The DNA sequence and analysis of human chromosome 14."
Nature 421:601-607(2003) [PubMed] [Europe PMC] [Abstract]

"The secreted protein discovery initiative (SPDI), a large-scale effort to identify novel human secreted and transmembrane proteins: a bioinformatics assessment."
Genome Res. 13:2265-2270(2003) [PubMed] [Europe PMC] [Abstract]

"Amnionless, essential for mouse gastrulation, is mutated in recessive hereditary megaloblastic anemia."
Nat. Genet. 33:426-429(2003) [PubMed] [Europe PMC] [Abstract]

"The functional cobalamin (vitamin B12)-intrinsic factor receptor is a novel complex of cubilin and amnionless."
Blood 103:1573-1579(2004) [PubMed] [Europe PMC] [Abstract]

"Imerslund-Grasbeck syndrome: new mutation in amnionless."
Pediatr. Int. 54:E19-E21(2012) [PubMed] [Europe PMC] [Abstract]