Translocon-associated protein alpha transcripts are induced by granulocyte-macrophage colony-stimulating factor and exhibit complex alternative polyadenylation.

The cloning of full length cDNA for the translocon-associated protein alpha subunit, previously called signal sequence receptor alpha, is reported as a result of differential display experiments in search of genes induced by granulocyte-macrophage colony-stimulating factor. Its messenger RNA was more abundant in growing cells than in either factor-deprived cells or quiescent cells and comprised four species, each having microheterogeneity, as a result of complex alternative polyadenylation apparently dependent on arrays of non-canonical polyadenylation signals. Radiation hybrid mapping of the gene showed that the gene is on the short arm of chromosome 6.