Most eukaryotic messenger RNAs are capped, spliced, and polyadenylated via co-transcriptional processes that are coupled to each other and to the transcription machinery. Coordination of these processes ensures correct RNA maturation and provides for the diversity of the transcribed isoforms. Thus, RNA processing is a chain of events in which the completion of one event is coupled to the initia...

The timely transition from vegetative to reproductive growth is vital for reproductive success in plants. It has been suggested that messenger RNA 3'-end processing plays a role in this transition. Specifically, two autonomous factors in the Arabidopsis thaliana flowering time control pathway, FY and FCA, are required for the alternative polyadenylation of FCA pre-mRNA. In this paper we provide...

We have studied in vitro cleavage/polyadenylation of precursor RNA containing herpes simplex virus type 2 poly A site sequences and have analyzed four RNA/protein complexes which form during in vitro reactions. Two complexes, A and B, form extremely rapidly and are then progressively replaced by a third complex, C which is produced following cleavage and polyadenylation of precursor RNA. Substi...

The VP55 subunit of the vaccinia virus-encoded poly(A) polymerase can add a maximum of 35 adenylates to the 3'-end of an RNA primer in a rapid and highly processive manner, whereas the VP55-VP39 heterodimer catalyzes the formation of poly(A) tails several hundred nucleotides in length. Here, we describe the overexpression of the VP39 subunit, its purification to near homogeneity, and its abilit...

Yth1p is the yeast homologue of the 30 kDa subunit of mammalian cleavage and polyadenylation specificity factor (CPSF). The protein is part of the cleavage and polyadenylation factor CPF, which includes cleavage factor II (CF II) and polyadenylation factor I (PF I), and is required for both steps in pre-mRNA 3'-end processing. Yth1p is an RNA-binding protein that was previously shown to be esse...

The link between polyadenylation (pA) and various biological, behavioral, and pathological events of eukaryotes underlines the need to develop in vivo polyadenylation assay methods for characterization of the cis-acting elements, trans-acting factors and environmental stimuli that affect polyadenylation efficiency and/or relative usage of two alternative polyadenylation (APA) sites. The current...

A large number of human genes have been found to contain more than one polyadenylation site (poly(A) site). These lead to multiple messenger ribonucleic acid (mRNA) transcripts, although some of them do not yield protein products. Like alternative initiation and alternative splicing, alternative polyadenylation (APA) contributes to the complexity of the overall pool of mRNA transcripts in human...

Cleavage and polyadenylation of a precursor mRNA is important for transcription termination, mRNA stability, and regulation of gene expression. This process is directed by a multitude of protein factors and cis elements in the pre-mRNA sequence surrounding the cleavage and polyadenylation site. Importantly, the location of the cleavage and polyadenylation site helps define the 3’ untranslated r...

Like most cellular mRNAs, the 5' end of HIV mRNAs is capped and the 3' end matured by the process of polyadenylation. There are, however, several rather unique and interesting aspects of these post-transcriptional processes on HIV transcripts. Capping of the highly structured 5' end of HIV mRNAs is influenced by the viral TAT protein and a population of HIV mRNAs contains a trimethyl-G cap remi...

In Xenopus development, the expression of several maternal mRNAs is regulated by cytoplasmic polyadenylation. CPEB and maskin, two factors that control polyadenylation-induced translation are present on the mitotic apparatus of animal pole blastomeres in embryos. Cyclin B1 protein and mRNA, whose translation is regulated by polyadenylation, are colocalized with CPEB and maskin. CPEB interacts w...