THE HUMAN RAE1 GENE IS A FUNCTIONAL HOMOLOG OF SCHIZOSACCHAROMYCES-POMBE RAE1 GENE INVOLVED IN NUCLEAR EXPORT OF POLY(A)(+) RNA

A Schizosaccharomyces pombe temperature-sensitive mutant, rae1-1, was previously identified by us as being defective in nuclear export of Po ly(A)(+) RNA when grown at restrictive temperature. Here, we report th e isolation of the human homologue of the S. pombe rae1 gene. The RAE1 genes are highly conserved in evolution in both structure and functio n. The human RAE1 cDNA, when expressed from the CMV-promoter, can supp ress partially the temperature sensitivity of the rae1-1 mutant. This is also reflected by increased Poly(A)+ RNA export at a restrictive te mperature. An epitope tagged human Rae1p localizes to both the nucleus and the cytoplasm in transiently transfected HeLa cells. We discuss t he potential role of Rae1p in nuclear cytoplasmic trafficking in yeast and higher eukaryotic cells. (C) 1997 Elsevier Science B.V.