Family With Sequence Similarity 38, Member A (FAM38A)

The deduced 2,090-amino acid human FAM38A protein contains a signal sequence, 24 transmembrane domains, and shares 83.1% amino acid identity with rat Fam38a. Northern blot analysis detected moderate expression of rat Fam38a in lung and kidney, and weak expression in heart, spleen, and liver. Double immunofluorescence studies colocalized rat Fam38a with Serca2 (ATP2A2) and beta-COP (COPB), markers for the endoplasmic reticulum (ER) and ER-Golgi intermediate compartment, respectively. In situ hybridization analysis of human brain sections detected FAM38A expression in neurons but not in quiescent astrocytes. In contrast, brain sections from Alzheimer disease (AD) patients displayed FAM38A expression in approximately half of the activated astrocytes located around classic senile plaques.