Alpha subunit of ATP-dependent 6-phosphofructokinase (PFK-1; EC 2.7.1.11) of Saccharomyces cerevisiae. Pfk1 and its paralog Pfk2 (beta subunit), which arose from an ancient duplication and each carry a fused catalytic/regulatory double-domain architecture, assemble into a cytosolic alpha4beta4 hetero-octamer that phosphorylates fructose 6-phosphate to fructose 1,6-bisphosphate, the committed and principal regulated step of glycolysis. The enzyme is allosterically activated by AMP and fructose 2,6-bisphosphate and inhibited by ATP. Single pfk1 mutants still ferment glucose but accumulate hexose phosphates, whereas pfk1 pfk2 double mutants cannot grow on glucose. Pfk1 also co-immunoprecipitates with the vacuolar V-ATPase, supports vacuolar/cytosolic pH homeostasis, and binds hundreds of mRNAs at short sequence motifs.
| GO Term | Evidence | Action | Reason |
|---|---|---|---|
| GO:0003730 mRNA 3'-UTR binding | IDA PMID:41816908 The yeast phosphofructokinase Ξ²-subunit has RNA unwinding ac... | KEEP AS NON CORE | Summary: Albihlal et al. RIP/CLIP-type analysis: Pfk1 binds mRNA targets at motifs enriched in CDS and 3'UTRs; purified recombinant protein binds these motifs. Reason: Recent single-study moonlighting function (Albihlal et al. 2026); experimentally supported but secondary to the glycolytic role. Supporting Evidence: PMID:41816908 Both Pfk1p and Pkf2p directly bind to short GA-, UC-, AU-, and U-rich motifs overrepresented in their mRNA targets. PMID:41816908 The bound mRNAs contain distinct repetitive RNA triplet motifs preferentially located either in CDS or 3β²UTRs, to which purified recombinant Pfks binds. |
| GO:0003730 mRNA 3'-UTR binding | IEA GO_REF:0000117 | KEEP AS NON CORE | Summary: ARBA rule for mRNA 3'-UTR binding, apparently derived from the same yeast PFK data; consistent for Pfk1. Reason: Recent single-study moonlighting function (Albihlal et al. 2026); experimentally supported but secondary to the glycolytic role. Supporting Evidence: PMID:41816908 The bound mRNAs contain distinct repetitive RNA triplet motifs preferentially located either in CDS or 3β²UTRs, to which purified recombinant Pfks binds. |
| GO:0003872 6-phosphofructokinase activity | IEA GO_REF:0000120 | ACCEPT | Summary: IEA from EC 2.7.1.11 / RHEA:16109, HAMAP and PFK InterPro signatures. Pfk1 is a catalytic-domain-containing subunit of the hetero-octameric PFK. Supporting Evidence: file:yeast/PFK1/PFK1-uniprot.txt Reaction=beta-D-fructose 6-phosphate + ATP = beta-D-fructose 1,6- |
| GO:0003872 6-phosphofructokinase activity | IGI PMID:3007939 Isolation and characterization of the two structural genes c... | ACCEPT | Summary: Heinisch: PFK activity rises only when PFK1 and PFK2 are co-overexpressed, showing Pfk1 contributes to the activity of the alpha4beta4 enzyme. Supporting Evidence: PMID:3007939 Subcloning of both genes in one multicopy vector (YEp13) and reintroduction into the yeast cell resulted in a 3.5-fold higher specific activity compared to the wild type. PMID:3007939 Transformation with one of the plasmids did not lead to an increase in phosphofructokinase activity. |
| GO:0003872 6-phosphofructokinase activity | IMP PMID:3007939 Isolation and characterization of the two structural genes c... | ACCEPT | Summary: Heinisch cloned PFK1 and PFK2 by complementation of pfk mutants; both subunits are needed for full PFK activity (contributes_to). Supporting Evidence: PMID:3007939 Yeast phosphofructokinase is an octamer composed of two different kinds of subunit. PMID:3007939 Subcloning of both genes in one multicopy vector (YEp13) and reintroduction into the yeast cell resulted in a 3.5-fold higher specific activity compared to the wild type. |
| GO:0005515 protein binding | IPI PMID:11805837 Systematic identification of protein complexes in Saccharomy... | REMOVE | Summary: Gavin et al. 2002 TAP-MS co-purified Pfk1 with Pfk2, its partner subunit in the PFK octamer. Reason: Uninformative 'protein binding'; the association is captured by part_of 6-phosphofructokinase complex. Supporting Evidence: PMID:11805837 it is feasible to identify directly protein complexes on a proteome-wide scale |
| GO:0005515 protein binding | IPI PMID:12051897 The first three-dimensional structure of phosphofructokinase... | REMOVE | Summary: Ruiz et al. EM of the 4alpha4beta PFK octamer documents the Pfk1-Pfk2 association. Reason: Uninformative 'protein binding'; captured by the PFK complex annotation. Supporting Evidence: PMID:12051897 Phosphofructokinase is an octamer composed of 4alpha and 4beta subunits arranged in a dihedral point group symmetry D(2). |
| GO:0005515 protein binding | IPI PMID:16429126 Proteome survey reveals modularity of the yeast cell machine... | REMOVE | Summary: Gavin et al. 2006 AP-MS co-purified Pfk1 with Pfk2. Reason: Uninformative 'protein binding'; captured by the PFK complex annotation. Supporting Evidence: PMID:16429126 Here we report the first genome-wide screen for complexes in an organism, budding yeast, using affinity purification and mass spectrometry. |
| GO:0005515 protein binding | IPI PMID:18719252 High-quality binary protein interaction map of the yeast int... | REMOVE | Summary: Yu et al. high-throughput Y2H detected Pfk1-Pfk2. Reason: Uninformative 'protein binding'; captured by the PFK complex annotation. Supporting Evidence: PMID:18719252 demonstrating that high-throughput yeast two-hybrid (Y2H) screening provides high-quality binary interaction information |
| GO:0005515 protein binding | IPI PMID:31454312 The role of structural pleiotropy and regulatory evolution i... | REMOVE | Summary: Marchant et al. paralog heteromer screen detected Pfk1-Pfk2 (the alpha/beta PFK paralogs). Reason: Uninformative 'protein binding'; captured by the PFK complex annotation. Supporting Evidence: PMID:31454312 we find that heteromerization is frequent among duplicated homomers and correlates with functional similarity between paralogs |
| GO:0005515 protein binding | IPI PMID:37968396 The social and structural architecture of the yeast protein ... | REMOVE | Summary: Michaelis et al. proteome-wide AP-MS recovered Pfk1-Pfk2. Reason: Uninformative 'protein binding'; captured by the PFK complex annotation. Supporting Evidence: PMID:37968396 to comprehensively map the interactome of Saccharomyces cerevisiae |
| GO:0005524 ATP binding | IEA GO_REF:0000002 | KEEP AS NON CORE | Summary: InterPro PFK (IPR009161) mapping to ATP binding; ATP is substrate and allosteric inhibitor. Reason: Substrate/effector binding; non-core. Supporting Evidence: file:yeast/PFK1/PFK1-uniprot.txt Reaction=beta-D-fructose 6-phosphate + ATP = beta-D-fructose 1,6- |
| GO:0005737 cytoplasm | EXP PMID:18313953 Detection and localisation of protein-protein interactions i... | ACCEPT | Summary: Barnard et al. split-GFP: Pfk1-Pfk2 complementation fluoresces in the cytoplasm. Supporting Evidence: PMID:18313953 labelling of the phosphofructokinase subunits, Pfk1p and Pfk2p, with N- and C-terminal EGFP fragments, respectively, resulted in green fluorescence in the cytoplasm |
| GO:0005737 cytoplasm | HDA PMID:11914276 Subcellular localization of the yeast proteome. | ACCEPT | Summary: Kumar et al. proteome-scale immunolocalization: Pfk1 cytoplasmic. Supporting Evidence: PMID:11914276 By high-throughput immunolocalization of tagged gene products, we have determined the subcellular localization of 2744 yeast proteins. |
| GO:0005737 cytoplasm | HDA PMID:22842922 Dissecting DNA damage response pathways by analysing protein... | ACCEPT | Summary: Tkach et al. GFP-collection imaging: Pfk1 cytoplasmic. Supporting Evidence: PMID:22842922 We use high-throughput microscopic screening of the yeast GFP fusion collection |
| GO:0005737 cytoplasm | IEA GO_REF:0000120 | ACCEPT | Summary: HAMAP/InterPro + UniProt subcellular-location mapping (Cytoplasm); correct. Supporting Evidence: PMID:18313953 labelling of the phosphofructokinase subunits, Pfk1p and Pfk2p, with N- and C-terminal EGFP fragments, respectively, resulted in green fluorescence in the cytoplasm |
| GO:0005739 mitochondrion | IBA GO_REF:0000033 | KEEP AS NON CORE | Summary: IBA mitochondrion from node PTN001008801 whose only donors are yeast Pfk1 and Pfk2 themselves (proteomic association data). Reason: Minor mitochondria-associated pool of the cytosolic PFK octamer; not where its core function is executed. Supporting Evidence: PMID:16962558 we show that all glycolytic enzymes are associated with mitochondria in yeast |
| GO:0005739 mitochondrion | IDA PMID:16962558 Enolase takes part in a macromolecular complex associated to... | KEEP AS NON CORE | Summary: Brandina et al.: all glycolytic enzymes are associated with yeast mitochondria. Reason: Minor mitochondria-associated pool of the cytosolic PFK octamer; not where its core function is executed. Supporting Evidence: PMID:16962558 we show that all glycolytic enzymes are associated with mitochondria in yeast |
| GO:0005739 mitochondrion | IEA GO_REF:0000117 | KEEP AS NON CORE | Summary: ARBA mitochondrion; reflects mitochondrial-association data. Reason: Minor mitochondria-associated pool of the cytosolic PFK octamer; not where its core function is executed. Supporting Evidence: PMID:16962558 we show that all glycolytic enzymes are associated with mitochondria in yeast |
| GO:0005741 mitochondrial outer membrane | IEA GO_REF:0000044 | KEEP AS NON CORE | Summary: UniProt subcellular location (mitochondrion outer membrane, peripheral) mapping; reflects proteomic association. Reason: Minor mitochondria-associated pool of the cytosolic PFK octamer; not where its core function is executed. Supporting Evidence: PMID:16962558 we show that all glycolytic enzymes are associated with mitochondria in yeast |
| GO:0005945 6-phosphofructokinase complex | IBA GO_REF:0000033 | ACCEPT | Summary: IBA 6-phosphofructokinase complex; yeast PFK is an alpha4beta4 octamer. Supporting Evidence: file:yeast/PFK1/PFK1-uniprot.txt SUBUNIT: Heterooctamer of 4 alpha and 4 beta chains. |
| GO:0005945 6-phosphofructokinase complex | IDA PMID:21241708 The crystal structures of eukaryotic phosphofructokinases fr... | ACCEPT | Summary: Banaszak et al. crystal structure of yeast PFK octamer. Supporting Evidence: PMID:21241708 The crystal structures of eukaryotic PFKs-from Saccharomyces cerevisiae and rabbit skeletal muscle-demonstrate how successive gene duplications and fusion are reflected in the protein structure |
| GO:0005945 6-phosphofructokinase complex | IDA PMID:4271029 Immunological evidence for non-identical subunits in yeast p... | ACCEPT | Summary: Herrmann et al. immunological evidence for non-identical (alpha/beta) subunits in yeast PFK (title only in cache). Supporting Evidence: PMID:4271029 Immunological evidence for non-identical subunits in yeast phosphofructokinase. |
| GO:0005945 6-phosphofructokinase complex | IDA PMID:6231961 Studies on the structure of yeast phosphofructokinase. | ACCEPT | Summary: Chaffotte et al. crosslinking demonstrated the octameric structure of yeast PFK. Supporting Evidence: PMID:6231961 crosslinking experiments demonstrated the octameric structure of yeast phosphofructokinase |
| GO:0005945 6-phosphofructokinase complex | IEA GO_REF:0000117 | ACCEPT | Summary: ARBA PFK complex; correct. Supporting Evidence: file:yeast/PFK1/PFK1-uniprot.txt SUBUNIT: Heterooctamer of 4 alpha and 4 beta chains. |
| GO:0005945 6-phosphofructokinase complex | IPI PMID:21241708 The crystal structures of eukaryotic phosphofructokinases fr... | ACCEPT | Summary: Crystal structure shows Pfk1 and Pfk2 assembled in the hetero-octamer. Supporting Evidence: PMID:21241708 The crystal structures of eukaryotic PFKs-from Saccharomyces cerevisiae and rabbit skeletal muscle-demonstrate how successive gene duplications and fusion are reflected in the protein structure |
| GO:0006002 fructose 6-phosphate metabolic process | IBA GO_REF:0000033 | ACCEPT | Summary: IBA fructose 6-phosphate metabolic process; PFK consumes F6P. Supporting Evidence: file:yeast/PFK1/PFK1-uniprot.txt Reaction=beta-D-fructose 6-phosphate + ATP = beta-D-fructose 1,6- |
| GO:0006002 fructose 6-phosphate metabolic process | IDA PMID:6219673 Similarity of activation of yeast phosphofructokinase by AMP... | ACCEPT | Summary: Nissler et al. kinetics of yeast PFK toward fructose 6-phosphate and its activation by AMP and F2,6BP. Supporting Evidence: PMID:6219673 Phosphofructokinase from yeast is effectively activated by AMP and fructose-2,6-bisphosphate by increasing the affinity of the enzyme to fructose-6-phosphate and the maximum activity toward this substrate. |
| GO:0006002 fructose 6-phosphate metabolic process | IEA GO_REF:0000120 | ACCEPT | Summary: IEA from ARBA/InterPro; correct. Supporting Evidence: file:yeast/PFK1/PFK1-uniprot.txt Reaction=beta-D-fructose 6-phosphate + ATP = beta-D-fructose 1,6- |
| GO:0006096 glycolysis | IDA PMID:3000145 Temporal organization of the phosphofructokinase/fructose-1,... | ACCEPT | Summary: Hofmann et al. reconstituted PFK/FBPase cycle with yeast PFK; glycolytic flux control. Supporting Evidence: PMID:3000145 an open and homogeneous reconstituted enzyme system containing phosphofructokinase, fructose-1,6-biphosphatase, pyruvate kinase, adenylate kinase and glucose 6-phosphate isomerase |
| GO:0006096 glycolysis | IDA PMID:6219673 Similarity of activation of yeast phosphofructokinase by AMP... | ACCEPT | Summary: Nissler et al. characterised the allosteric glycolytic PFK of yeast. Supporting Evidence: PMID:6219673 Phosphofructokinase from yeast is effectively activated by AMP and fructose-2,6-bisphosphate by increasing the affinity of the enzyme to fructose-6-phosphate and the maximum activity toward this substrate. |
| GO:0006096 glycolysis | IEA GO_REF:0000120 | ACCEPT | Summary: IEA from UniPathway/HAMAP (glycolysis step 3/4); correct. Supporting Evidence: file:yeast/PFK1/PFK1-uniprot.txt PATHWAY: Carbohydrate degradation; glycolysis; D-glyceraldehyde 3- |
| GO:0006096 glycolysis | IGI PMID:2965996 Construction and physiological characterization of mutants d... | ACCEPT | Summary: pfk1 pfk2 double disruptants cannot grow on 2% glucose; F6P/G6P accumulate and FBP falls below detection. Supporting Evidence: PMID:2965996 A haploid yeast strain containing both disrupted copies of the PFK-genes is not capable of growing on rich medium containing 2% glucose. PMID:2965996 accumulated fructose-6-phosphate and glucose-6-phosphate over wild type levels and showed decreased levels of fructose-1,6-bisphosphate |
| GO:0006096 glycolysis | IMP PMID:2965996 Construction and physiological characterization of mutants d... | ACCEPT | Summary: Pfk1 single disruptants accumulate F6P/G6P and show decreased FBP, though they still ferment glucose. Supporting Evidence: PMID:2965996 accumulated fructose-6-phosphate and glucose-6-phosphate over wild type levels and showed decreased levels of fructose-1,6-bisphosphate PMID:2965996 the single disruption mutants still fermented glucose to ethanol and CO2 |
| GO:0030388 fructose 1,6-bisphosphate metabolic process | IBA GO_REF:0000033 | ACCEPT | Summary: IBA fructose 1,6-bisphosphate metabolic process; PFK forms FBP. Supporting Evidence: file:yeast/PFK1/PFK1-uniprot.txt Reaction=beta-D-fructose 6-phosphate + ATP = beta-D-fructose 1,6- |
| GO:0043022 ribosome binding | IDA PMID:41816908 The yeast phosphofructokinase Ξ²-subunit has RNA unwinding ac... | REMOVE | Summary: The cited study found ~20% of Pfk1 co-sedimenting with polysomes, but Pfk1 did not dissociate upon EDTA disassembly of ribosomes or glucose removal; the authors conclude Pfk1 is not directly associated with translating ribosomes (in contrast to Pfk2). Reason: Contradicted by the full text of the cited paper itself. Supporting Evidence: PMID:41816908 corroborating the notion that Pfk1p is not directly associated with translating ribosomes in the absence of Pfk2p |
| GO:0043022 ribosome binding | IEA GO_REF:0000117 | REMOVE | Summary: ARBA ribosome binding applied to Pfk1; experimental data show ribosome association is specific to Pfk2, not Pfk1. Reason: Contradicted by the source study. Supporting Evidence: PMID:41816908 corroborating the notion that Pfk1p is not directly associated with translating ribosomes in the absence of Pfk2p |
| GO:0046961 proton-transporting ATPase activity, rotational mechanism | IGI PMID:18632794 Human H+ATPase a4 subunit mutations causing renal tubular ac... | MARK AS OVER ANNOTATED | Summary: Su et al. showed PFK co-immunoprecipitates with the V-ATPase a-subunit and pfk loss causes a vma-like pH-conditional phenotype. contributes_to implies Pfk1 is a functional part of the proton pump; PFK is a binding partner/regulator, not a V-ATPase subunit, and the paper's mechanistic data are largely on human a4/PFK-1. Reason: Regulatory interaction mis-cast as contribution to the pump's catalytic activity. Supporting Evidence: PMID:18632794 we coimmunoprecipitated the vacuolar H+ATPase and Pfk from KEBY9 reconstituted with Vph1p PMID:18632794 the absence of Pfk imposes a pH-conditional growth phenotype whereby growth cannot proceed at raised pH, indicating defective vacuolar function |
| GO:0048027 mRNA 5'-UTR binding | IDA PMID:41816908 The yeast phosphofructokinase Ξ²-subunit has RNA unwinding ac... | KEEP AS NON CORE | Summary: Albihlal et al.: Pfk1 binds U-rich elements including in mRNA 5'UTRs (e.g. CLN3). Reason: Recent single-study moonlighting function (Albihlal et al. 2026); experimentally supported but secondary to the glycolytic role. Supporting Evidence: PMID:41816908 Both Pfk1p and Pkf2p directly bind to short GA-, UC-, AU-, and U-rich motifs overrepresented in their mRNA targets. PMID:41816908 the CLN3-5β²UTR covers two proceeding U-rich element |
| GO:0048027 mRNA 5'-UTR binding | IEA GO_REF:0000117 | KEEP AS NON CORE | Summary: ARBA mRNA 5'-UTR binding derived from yeast PFK data. Reason: Recent single-study moonlighting function (Albihlal et al. 2026); experimentally supported but secondary to the glycolytic role. Supporting Evidence: PMID:41816908 Both Pfk1p and Pkf2p directly bind to short GA-, UC-, AU-, and U-rich motifs overrepresented in their mRNA targets. |
| GO:0051453 regulation of intracellular pH | IEA GO_REF:0000117 | KEEP AS NON CORE | Summary: ARBA regulation of intracellular pH, derived from yeast PFK/V-ATPase data. Reason: Indirect/regulatory role; non-core. Supporting Evidence: PMID:24860096 In vivo, the pfk1Ξ and pfk2Ξ vacuoles were alkalinized and the cytosol acidified, suggestive of impaired V-ATPase proton transport. |
| GO:0051453 regulation of intracellular pH | IMP PMID:24860096 Yeast phosphofructokinase-1 subunit Pfk2p is necessary for p... | KEEP AS NON CORE | Summary: Chan & Parra: pfk1 and pfk2 deletions alkalinise vacuoles and acidify cytosol. Reason: Experimental; likely via glycolytic support of V-ATPase. Non-core. Supporting Evidence: PMID:24860096 In vivo, the pfk1Ξ and pfk2Ξ vacuoles were alkalinized and the cytosol acidified, suggestive of impaired V-ATPase proton transport. |
| GO:0061621 obsolete canonical glycolysis | IBA GO_REF:0000033 | MODIFY | Summary: IBA to obsolete 'canonical glycolysis'; biology correct, term retired. Reason: Update to current glycolysis term. Proposed replacements: glycolysis Supporting Evidence: file:yeast/PFK1/PFK1-uniprot.txt PATHWAY: Carbohydrate degradation; glycolysis; D-glyceraldehyde 3- |
| GO:0070095 fructose-6-phosphate binding | IBA GO_REF:0000033 | KEEP AS NON CORE | Summary: IBA fructose-6-phosphate binding (substrate binding). Reason: Implied by catalytic activity; non-core. Supporting Evidence: PMID:6219673 Phosphofructokinase from yeast is effectively activated by AMP and fructose-2,6-bisphosphate by increasing the affinity of the enzyme to fructose-6-phosphate and the maximum activity toward this substrate. |
| GO:1902600 proton transmembrane transport | IEA GO_REF:0000117 | MARK AS OVER ANNOTATED | Summary: ARBA proton transmembrane transport derived from the yeast IGI below; PFK does not translocate protons. Reason: PFK supports/regulates V-ATPase but does not transport protons. Supporting Evidence: PMID:24860096 Both phosphofructokinase-1 subunits co-immunoprecipitated with V-ATPase in wild-type cells |
| GO:1902600 proton transmembrane transport | IGI PMID:18632794 Human H+ATPase a4 subunit mutations causing renal tubular ac... | MARK AS OVER ANNOTATED | Summary: Su et al.: loss of PFK impairs vacuolar function; PFK binds the V-ATPase a-subunit. Pfk1 is a regulator of the pump, not a participant in proton translocation. Reason: Regulatory role upstream of transport. Supporting Evidence: PMID:18632794 the absence of Pfk imposes a pH-conditional growth phenotype whereby growth cannot proceed at raised pH, indicating defective vacuolar function |
| GO:1990715 mRNA CDS binding | IDA PMID:41816908 The yeast phosphofructokinase Ξ²-subunit has RNA unwinding ac... | KEEP AS NON CORE | Summary: Albihlal et al.: Pfk1-bound motifs are enriched in CDS regions. Reason: Recent single-study moonlighting function (Albihlal et al. 2026); experimentally supported but secondary to the glycolytic role. Supporting Evidence: PMID:41816908 The bound mRNAs contain distinct repetitive RNA triplet motifs preferentially located either in CDS or 3β²UTRs, to which purified recombinant Pfks binds. |
| GO:1990715 mRNA CDS binding | IEA GO_REF:0000117 | KEEP AS NON CORE | Summary: ARBA mRNA CDS binding derived from yeast PFK data. Reason: Recent single-study moonlighting function (Albihlal et al. 2026); experimentally supported but secondary to the glycolytic role. Supporting Evidence: PMID:41816908 The bound mRNAs contain distinct repetitive RNA triplet motifs preferentially located either in CDS or 3β²UTRs, to which purified recombinant Pfks binds. |
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Alpha subunit of heterooctameric phosphofructokinase; involved in glycolysis, indispensable for anaerobic growth, activated by fructose-2,6-bisphosphate and AMP, mutation inhibits glucose induction of cell cycle-related genes; binds short mRNA sequence repeats and associates with ribosomes
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