In budding yeasts, Paf1 is part of the Paf1 complex, an RNA polymerase II-associated protein complex containing Paf1, Cdc73, Ctr9, Rtf1 and Leo1 []. Paf1 complex is involved in histone modifications, transcription elongation and other gene expression processes that include transcript site selection []. This entry also includes Paf1 homologues from animals and plants. Human Paf1, also known as PD2 (pancreatic differentiation 2), is associated with tumorigenesis []. Human Paf1 complex (Paf1C) consists of Paf1, Cdc73, Ctr9, Rtf1, Leo1 and Wdr61 (Ski8). As in yeast, the human Paf1C has a central role in co-transcriptional histone modifications []. Human Paf1 complex has a crucial role in the antiviral response []. Arabidopsis Paf1C related proteins such as VIP4 (Leo1), VIP5 (Rtf1), ELF7 (Paf1), ELF8 (Ctr9) and ATXR7 (Set1) are required for the induction of seed dormancy. They control both germination and flowering time [].
This is the N-terminal region of Cdc73 (cell division cycle 73). Cdc73 forms part of the Paf1 post-initiation complex []. As part of the Paf1 complex, Cdc73 associates with RNA-polymerase II and is involved in several transcriptional and posttranscriptional events. In vertebrates, the protein encoded by HRPT2/CCdc73 is known as Parafibromin, and acts as a tumour suppressor [, ].
In budding yeasts, Leo1 is part of the Paf1 complex, an RNA polymerase II-associated protein complex containing Paf1, Cdc73, Ctr9, Rtf1 and Leo1. Paf1 complex is involved in histone modifications, transcription elongation and other gene expression processes that include transcript site selection []. This entry also includes Leo1 homologues from animals and plants. Human Leo1, also known as RDL, is a component of the human Paf1 complex (Paf1C), which consists of Paf1, Cdc73, Ctr9, Rtf1, Leo1 and Wdr61 (Ski8). As in yeast, the human Paf1C has a central role in co-transcriptional histone modifications []. Human Leo1 promotes senescence of 2BS fibroblasts [].Arabidopsis Paf1C related proteins such as VIP4 (Leo1), VIP5 (Rtf1), ELF7 (Paf1), ELF8 (Ctr9) and ATXR7 (Set1) are required for the induction of seed dormancy. They control both germination and flowering time [].
This entry includes budding yeast RNA polymerase-associated protein Ctr9 and its homologues from other yeasts, animals and plants. The homologue in fission yeast is known as tetratricopeptide repeat protein 1 (Tpr1) [].Budding yeast Ctr9 is part of the Paf1 complex, an RNA polymerase II-associated protein complex containing Paf1, Cdc73, Ctr9, Rtf1 and Leo1 []. Paf1 complex is involved in histone modifications, transcription elongation and other gene expression processes that include transcript site selection []. Human Paf1 complex (Paf1C) consists of Paf1, Cdc73, Ctr9, Rtf1, Leo1 and Wdr61 (Ski8). As in yeast, the human Paf1C has a central role in co-transcriptional histone modifications [].Arabidopsis Paf1C related proteins such as VIP4 (Leo1), VIP5 (Rtf1), ELF7 (Paf1), ELF8 (Ctr9) and ATXR7 (Set1) are required for the induction of seed dormancy. They control both germination and flowering time [].
CDC73 is an RNA polymerase II accessory factor [], and forms part of the Paf1 complex that has roles in post-initiation events []. More specifically, crystal structure analysis shows the C terminus to be a Ras-like domain that adopts a fold that is highly similar to GTPases of the Ras superfamily. The C-terminal domain contains a large but comparatively flat surface of highly conserved residues, devoid of ligand. Deletion of the Cdc73 C-domain significantly reduces Paf1C occupancy on active genes, which means that the Cdc73 C-domain plays a role in promoting association of Paf1C with chromatin []. The canonical nucleotide binding pocket is altered in CDC73, and there is no nucleotide ligand, but it contributes to histone methylation and Paf1 complex (Paf1C) recruitment to active genes. Thus, together with Rtf1, it combines to couple Paf1C to elongating polymerase [].
CDC73 is an RNA polymerase II accessory factor [], and forms part of the Paf1 complex that has roles in post-initiation events []. More specifically, crystal structure analysis shows the C terminus to be a Ras-like domain that adopts a fold that is highly similar to GTPases of the Ras superfamily. The C-terminal domain contains a large but comparatively flat surface of highly conserved residues, devoid of ligand. Deletion of the Cdc73 C-domain significantly reduces Paf1C occupancy on active genes, which means that the Cdc73 C-domain plays a role in promoting association of Paf1C with chromatin []. The canonical nucleotide binding pocket is altered in CDC73, and there is no nucleotide ligand, but it contributes to histone methylation and Paf1 complex (Paf1C) recruitment to active genes. Thus, together with Rtf1, it combines to couple Paf1C to elongating polymerase [].
This entry includes Cdc73 from budding yeasts and its animal homologue, parafibromin. They are part of the Paf1 complex involved in histone modifications, transcription elongation and other gene expression processes that include transcript site selection [].In budding yeasts, Paf1 is an RNA polymerase II-associated protein complex containing Paf1, Cdc73, Ctr9, Rtf1 and Leo1. It is required for full expression of a subset of yeast genes, particularly those responsive to signals from the Pkc1/MAP kinase cascade. The complex appears to play an essential role in RNA elongation []. Human parafibromin is a tumour suppressor that may facilitate association of 3' mRNA processing factors with actively-transcribed chromatin. It is a component of the human Paf1 complex (Paf1C), which consists of Paf1, Cdc73, Ctr9, Rtf1, Leo1 and Wdr61 (Ski8). As in yeast, the human Paf1C has a central role in co-transcriptional histone modifications []. The Arabidopsis Cdc73 (also known as PLANT HOMOLOGOUS TO PARAFIBROMIN ,PHP) assists in regulating expression of genes within H3K27ME3-enriched chromatin []and participates in the modification of FLOWERING LOCUS C (FLC) chromatin [].
The yeast Paf1 complex consists of Pfa1, Rtf1, Cdc73, Ctr9, and Leo1. The complex regulates histone H2B ubiquitination, histone H3 methylation, RNA polymerase II carboxy-terminal domain (CTD) Ser2 phosphorylation, and RNA 3' end processing. The conservation of Paf1 complex function in higher eukaryotes has been confirmed in human cells, Drosophila and Arabidopsis. The Plus3 domain spans the most conserved regions of the Rtf1 protein and is surrounded by regions of low complexity and coiled-coil propensity []. It contains only a limited number of highly conserved amino acids, among which are three positively charged residues that gave the Plus3 domain its name. The capacity to bind single-stranded DNA is at least one function of the Plus3 domain [].The plus-3 domain is about 90 residues in length and is often found associated with the GYF domain (). The Plus3 domain structure consists of six alpha helices intervened by a sequence of six beta strands in a mixed alpha/beta topology. Beta strands 1, 2, 5, and 6 compose a four-stranded antiparallel beta sheet with a β-hairpin insertion formed by strands 3 and 4. The N-terminal helices alpha1-alpha3 and C-terminal helix alpha6 pack together to form an alpha subdomain, while the beta strands and the small 3(10) helix alpha 4 form a beta subdomain. The two subdomains pack together to form a compact, globular protein [].
The yeast Paf1 complex consists of Pfa1, Rtf1, Cdc73, Ctr9, and Leo1. The complex regulates histone H2B ubiquitination, histone H3 methylation, RNA polymerase II carboxy-terminal domain (CTD) Ser2 phosphorylation, and RNA 3' end processing. The conservation of Paf1 complex function in higher eukaryotes has been confirmed in human cells, Drosophila and Arabidopsis. The Plus3 domain spans the most conserved regions of the Rtf1 protein and is surrounded by regions of low complexity and coiled-coil propensity []. It contains only a limited number of highly conserved amino acids, among which are three positively charged residues that gave the Plus3 domain its name. The capacity to bind single-stranded DNA is at least one function of the Plus3 domain [].The plus-3 domain is about 90 residues in length and is often found associated with the GYF domain (). The Plus3 domain structure consists of six alpha helices intervened by a sequence of six beta strands in a mixed alpha/beta topology. Beta strands 1, 2, 5, and 6 compose a four-stranded antiparallel beta sheet with a β-hairpin insertion formed by strands 3 and 4. The N-terminal helices alpha1-alpha3 and C-terminal helix alpha6 pack together to form an alpha subdomain, while the beta strands and the small 3(10) helix alpha 4 form a beta subdomain. The two subdomains pack together to form a compact, globular protein [].
