Hrp1, a sequence-specific RNA-binding protein that shuttles between the nucleus and the cytoplasm, is required for mRNA 3'-end formation in yeast.
In yeast, four factors (CF I, CF II, PF I, and PAP) are required for accurate pre-mRNA cleavage and polyadenylation in vitro. CF I can be separated further into CF IA and CF IB. Here we show that CF IB is the 73-kD Hrp1 protein. Recombinant Hrp1p made in Escherichia coli provides full CF IB function in both cleavage and poly(A) addition assays. Consistent with the presence of two RRM-type motifs, Hrp1p can be UV cross-linked to RNA, and this specific interaction requires the (UA)6 polyadenylation efficiency element. Furthermore, the CF II factor enhances the binding of Hrp1p to the RNA precursor. A temperature-sensitive mutant in HRP1 yields mRNAs with shorter poly(A) tails when grown at the nonpermissive temperature. Genetic analyses indicate that Hrp1p interacts with Rna15p and Rna14p, two components of CF 1A. The HRP1 gene was originally isolated as a suppressor of a temperature-sensitive npl3 allele, a gene encoding a protein involved in mRNA export. Like Npl3p, Hrp1p shuttles between the nucleus and cytoplasm, providing a potential link between 3'-end processing and mRNA export from the nucleus.
Kessler
M M
MM
Department of Molecular Biology and Microbiology, Tufts University School of Medicine, Boston, Massachusetts 02111, USA.
Henry
M F
MF
Shen
E
E
Zhao
J
J
Gross
S
S
Silver
P A
PA
Moore
C L
CL
D000595:Amino Acid Sequence; D002467:Cell Nucleus / Q000378:metabolism; D003593:Cytoplasm / Q000378:metabolism; D004926:Escherichia coli / Q000235:genetics; D005656:Fungal Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D000081035:Heterogeneous Nuclear Ribonucleoprotein D0; D034502:Heterogeneous-Nuclear Ribonucleoprotein D; D008969:Molecular Sequence Data; D016297:Mutagenesis, Site-Directed; D010957:Plasmids; D011061:Poly A / Q000235:genetics / Q000378:metabolism; D012322:RNA Precursors / Q000235:genetics / Q000378:metabolism; D012323:RNA Processing, Post-Transcriptional; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism*; D016601:RNA-Binding Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D011994:Recombinant Proteins / Q000737:chemistry / Q000378:metabolism; D012261:Ribonucleoproteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D012441:Saccharomyces cerevisiae / Q000235:genetics / Q000378:metabolism*; D029701:Saccharomyces cerevisiae Proteins; D017386:Sequence Homology, Amino Acid; D039221:mRNA Cleavage and Polyadenylation Factors
D005656:Fungal Proteins; C512636:HRP1 protein, S cerevisiae; D000081035:Heterogeneous Nuclear Ribonucleoprotein D0; D034502:Heterogeneous-Nuclear Ribonucleoprotein D; D012322:RNA Precursors; D012333:RNA, Messenger; D016601:RNA-Binding Proteins; D011994:Recombinant Proteins; D012261:Ribonucleoproteins; D029701:Saccharomyces cerevisiae Proteins; D039221:mRNA Cleavage and Polyadenylation Factors; D011061:Poly A