An Arabidopsis Fip1 homolog interacts with RNA and provides conceptual links with a number of other polyadenylation factor subunits.

摘要: The protein Fip1 is an important subunit of the eukaryotic polyadenylation apparatus, since it provides a bridge sorts between poly(A) polymerase, other subunits and substrate RNA. In this study, previously unreported Arabidopsis homolog characterized. gene for resides on chromosome V encodes 1196-amino acid polypeptide. Yeast two-hybrid in vitro assays indicate that N-terminal 137 amino acids interact with polymerase (PAP). This domain also stimulates activity PAP. Interestingly, part interacts homologs CstF77, CPSF30, CFIm-25, PabN1. interactions CFIm-25 are reminiscent various respects similar seen yeast mammals, although participates these has no apparent counterpart proteins. Interactions PabN1 have not been reported systems; may represent plant-specific associations. C-terminal 789 were found to contain RNA-binding domain; correlated intact arginine-rich region had marked preference poly(G) among four homopolymers studied. These results Fip1, like its human counterpart, protein. Moreover, they provide conceptual links PAP several factor homologs.